Ginkgo – much more than a herb for cognition (part 1).

Extracts made from leaves of the ginkgo tree (Ginkgo biloba) are a widely used herbal medicine, mostly due to a reputation to help support cognitive functions in both healthy young(1,2) and middle-aged(3,4) people. However, numerous other potential applications exist for the bitter leaves of this beautiful tree, which has actions as a strong antioxidant and microcirculatory enhancer(5).


More than 400 of the 4000 papers on ginkgo published in the peer-reviewed scientific literature, relate to protective effects against nerve damage or degeneration, in in vitro and animal studies. These include reduced neurodegeneration and oedema in animal models of brain ischaemia(6-8), implicating potential applications of ginkgo to help prevent or reduce ischaemia-induced damage in stroke prone patients(9).

Clinical studies in humans show improved neurological and cognitive outcomes when ginkgo is taken in the immediate period following a stroke(10-12), without increasing the incidence of vascular events. The largest of these was a Chinese multicentre study where 450mg ginkgo extract was given daily together with 100mg aspirin for a 6 month period, in 348 post-stroke patients(11). While these results are promising, further trials involving greater patient numbers and longer treatment durations, are needed.

Parkinson’s disease is a neurodegenerative disorder characterized by the loss of dopaminergic neurons and is associated with oxidative stress, neuroinflammation and apoptosis. Studies in animal models of Parkinsons disease have implicated beneficial actions of ginkgo or its constituents(13-18). These include a reduction in elevated oxidative stress markers and inflammatory cytokines, reduced locomotion impairment(13), clearance of the alpha-synuclein (α-syn) protein by ginkgolic acid(17), and regulation of brain copper levels(19).

Two small trials involving a daily dosage of 240mg extract have investigated ginkgo’s effects on patients with multiple sclerosis, but with mixed results(20, 21).

Potential applications exist also for ginkgo to help protect against neurodegenerative retinal diseases such as macular degeneration or glaucoma, and diabetes.

Glaucoma is primarily a condition of raised intraocular pressure, but even successful intraocular pressure reduction does not stop the progression of glaucoma in all patients. As vascular dysregulation, reduced microcirculation, oxidative stress and inflammation are contributory to its development, ginkgo has relevant pharmacological actions that may be useful(22-25).

Ginkgo pretreatment and early post-treatment has been shown to protect retinal ganglion cells from damage in a rat model of chronic glaucoma(26). Few clinical trials have taken place apart from a Korean trial involving 99 patients given ginkgo for 2 years, which reported improved visual function in some patients with normal tension glaucoma(27). Given the limited treatment options for this increasingly common condition, the use of ginkgo as an adjuvant or preventive therapy should be further explored(24).

Similar potential benefits would seem to exist for age-related macular degeneration (AMD), the leading cause of irreversible blindness in adults over 50 years of age. Two trials involving a total of 119 people have reported some positive effects of ginkgo on vision in AMD patients, for doses of 160mg or 240mg per day taken over a 6 month period(28). A Russian trial involving 240mg ginkgo extract together with lutein, zeaxanthin, vitamins C, E, A and B2, rutin, zinc, selenium and bilberry in diabetic patients with initial stages of diabetic retinopathy or combined diabetic retinopathy and AMD, also found evidence of both preventive and treatment benefits(29). Again however, larger trials and for longer treatment periods, are needed.

Potential benefits in diabetes:

Type 2 Diabetes mellitus is one of the major diseases of the 21st century, and is putting an increasing burden on health care budgets. While dietary education and interventions and exercise can assist, and oral hypoglycaemic drugs or insulin are often prescribed, other interventions to reduce drug medication needs and/or improve patient outcomes can have huge benefits.

Diabetes is primarily a condition of poor blood glucose control, but vascular dysfunction often develops and long term outcomes can include development of conditions such as retinal neuropathy and blindness, peripheral vascular disease leading to leg ulcers, and glomerulonephritis leading to deterioration in kidney function.

Various studies in animals suggest a possible role for ginkgo in protecting against such neuropathies. One in diabetic rats found that 4 weeks treatment with ginkgo and magnetised water protected type 2 diabetic rat kidneys from nephrotoxic damages, effects associated with reduced hyperlipidemia, uraemia, oxidative stress, and renal dysfunction(30). Another found ginkgo pretreatment improved neurological scores, and reduced cerebral infarct volume and acute cerebral ischemia‑reperfusion injury in diabetic rats(31). Improvement in cognitive function has been reported in elderly diabetic mice(32), as has reduced plaque lipid deposition and aorta atherosclerosis, and reduced expressions of cytokines and other inflammatory markers (33). Doses used in these animal studies, however, were generally significantly higher than those normally recommended in humans.

Few clinical trials have been undertaken to date and patient numbers were relatively small. Various trials involving a combined treatment of diabetic patients with a particular combination of various Chinese herbs and ginkgo reported improved outcomes, although the contribution of the relatively low dose of 24mg ginkgo extract used in these studies is unknown(34-36).

Another trial found an improved response through adding ginkgo to the oral hypoglycaemic drug metformin for 90 days(37). Blood levels of fasting glucose, insulin, and HbA1c (glycated haemoglobin), whose elevation is linked to risks of diabetic complications, showed a greater reduction in the combined ginkgo-metformin treatment group, than with metformin treatment alone.

Ginkgo would seem to offer various relevant potential benefits in the prevention and management also of Metabolic syndrome(38). This is an insidious cluster of conditions including high blood pressure, diabetes, obesity and high blood lipids, and associated with an increased risk of cardiovascular disease events. Given the increasing prevalence of Metabolic syndrome including in up to a third of American adults, herbal agents such as ginkgo with diverse but relevant pharmacological actions, should receive greater attention.



  1. Kennedy DO et al, Psychopharmacology (Berl) 2000 Sep;151(4):416-23.
  2. Kennedy DO et al, Physiol Behav 2002 Apr 15;75(5):739-51
  3. Kaschel R et al, Phytomedicine 2011 Nov 15;18(14):1202-7
  4. Cieza A et al, Arch Med Res. Sep-Oct 2003;34(5):373-81.
  5. Wu Y et al, Phytomedicine. 2008;15:164–9.
  6. Saleem S et al, Stroke. 2008 Dec;39(12):3389-96.
  7. Lang D et al, Brain Res 2011 Nov 24;1425:155-63
  8. Tulsulkar J et al, Transl Stroke Res. 2016 Apr;7(2):120-31.
  9. Mdzinarishvili A et al, J Pharm Pharm Sci 2012;15(1):94-102).
  10. Oskouei DS et al, J Stroke Cerebrovasc Dis. 2013 Nov;22(8):e557-63.
  11. Li S et al, Stroke Vasc Neurol. 2017 Dec 18;2(4):189-197.
  12. Ji H et al, Medicine (Baltimore). 2020 Jan;99(2):e18568
  13. Rojas P et al, Nutrition. Nov-Dec 2012;28(11-12):1081-8.
  14. El-Ghazaly MA et al, Toxicol Ind Health. 2015 Dec;31(12):1128-43
  15. Wang YQ et al, Free Radic Res. 2015;49(9):1069-80
  16. Kuang S et al, Can J Neurol Sci. 2018 Mar;45(2):182-187
  17. Vijayakumaran S et al, Mol Cell Neurosci. 2019 Dec;101:103416.
  18. Mohammed N et al, Curr Pharm Biotechnol. 2020 Mar 20.
  19. Rojas P et al, Nutrition. 2009 Apr;25(4):482-5
  20. Johnson SK et al, Explore (NY). 2006 Jan;2(1):19-24
  21. Lovera JF et al, Neurology. 2012 Sep 18;79(12):1278-84
  22. Doozandeh A et al, J Ophthalmic Vis Res. Apr-Jun 2016;11(2):209-20.
  23. Martinez-Solis I et al, Planta Med. 2019 Nov;85(17):1292-1303.
  24. Cybulska-Heinrich AK et al, Mol Vis. 2012;18:390-402.
  25. Bungau S et al, Oxid Med Cell Longev. 2019 Feb 12;2019:9783429.
  26. Hirooka K et al, Curr Eye Res. 2004;28:153–7
  27. Shim SH et al, J Med Food. 2012 Sep;15(9):818-23
  28. Evans JR. Cochrane Database Syst Rev. 2013 Jan 31;2013(1):CD001775.
  29. Moshetova LK et al, Vestn Oftalmol May-Jun 2015;131(3):34-44
  30. Zayed AE et al, Oxid Med Cell Longev. 2018 Jun 11;2018:1785614.
  31. Yan M et al, Mol Med Rep. 2020 Apr;21(4):1809-1818
  32. Guan ZF et al, Metab Brain Dis 2018 33(6):1887-1897.
  33. Tian J et al, Oxid Med Cell Longev. 2019 Mar 18;2019:8134678.
  34. An XF et al, Zhongguo Zhong Xi Jie He Za Zhi. 2016; 36(6):674-677.
  35. Zhao Y et al, Complement Ther Med. 2018 Oct;40:120-125.
  36. Shi R et al, Front Endocrinol (Lausanne). 2019 Feb 22;10:100
  37. Aziz TA et al, Drug Des Devel Ther. 2018 Apr 5;12:735-742
  38. Eisvand F et al, Phytother Res. 2020 Feb 25.

Covid -19: An Opportunity for the New Zealand economy

The Covid-19 pandemic is having and will continue to have a huge impact on the economic wellness of all countries. While effects are far-reaching and multiple industries will be impacted, two of New Zealand’s largest sources of employment and export earnings, have been hard hit by this clever virus, resulting in a sudden increase in financial stress and unemployment. The two industries being tourism and forestry.

With border restrictions and consequently less overseas visitors likely to continue for the foreseeable future, and in the global economic slowdown causing reduced demand for forestry products, the hit on these sectors of our economy from Covid-19 will be harsh. This will be particularly so for people living in New Zealand’s rural regions and small towns, where businesses based around tourism and forestry are often the foundation of the local economy. A re-evaluation of New Zealand’s competitive advantages and emerging opportunities to provide alternative sources of employment and exports in the ‘post Covid-19 world’, is therefore a priority for both the New Zealand government, and many businesses.


New Zealand’s Strategic Advantages:

The diversity and scale of our natural and rural landscapes and environment, is a key strength. This is not only appealing to tourists, but provides an ideal environment to grow a wide range of different plant types in different geographical regions. We already produce more food than is required for the local population, and export many products derived from plants and trees. Exports of wine, kiwifruit, avocados, apples, berries and other fruits, nuts and cereals, have all risen substantially over the past five years. The future of food will be more based upon plants and less on animal products, than it is now.

Another strategic advantage New Zealand has, is being a relatively small country with a low population density, and with a track record of adapting quickly to global economic changes and shifting market trends. This we have had to do several times in our past, each with good long term outcomes. Examples include the assignment of thousands of unemployed men to tree planting and further establishing a forestry industry during the Great Depression in the 1930’s, the shift to new markets after being too dependent on Britain for exports when that country joined the EU in 1973, and the early decisions by Air New Zealand to develop new and emerging markets and invest into more fuel-efficient planes, at a time when most airlines were becoming increasingly under stress early this century.

With Covid-19 being the latest global stressor to our economy, as well as future impacts of climate change and increasingly frequent droughts and floods, a fresh and forward thinking approach to rejuvenating regional and rural economies, is called for. In fact the non-native based forestry industry and elements of our tourism industry had already grown to the point of being unsustainable and having increasingly negative environmental and sociological impacts for some time. Some re-setting of their scale and our dependency on them was needed even before Covid-19. Nature has been protesting about the mounting negative impacts from carbon thirsty human activities for some time now, and there is a need to moderate our excessively animal based farming model for the wellness of both the planet and future generations.


Phytomedicines: The Big Opportunity

Many of our existing food and beverage products have health enhancing properties, but are just the tip of the iceberg in our potential to grow and add value to, a much wider range of plant-derived herbal or phyto (‘plant’) medicines.

Global demand for herbal medicines and their raw materials has been rising for many years due to a multitude of powerful market drivers, and Covid-19 has spurred this even more. This includes demand for products aimed at supporting immunity and stress, but also a wide range of other health and wellness applications.

Aging populations, increasing costs of new drugs and hospital care, and the associated budgetary constraints by government health agencies, are also catalysing increased interest in natural health products. Finally, the increasing evidence for the effectiveness of various phytomedicine interventions for a wide range of health conditions, supported by traditional use as well as modern science.

Covid-19 has dealt us a sudden reminder that drugs don’t always provide all the answers, and the void of antiviral drugs or vaccines to prevent or treat this virus, should be a wakeup call to us all. And then there’s that other closely related and worsening nightmare of antibiotic resistance, which already contributes to more than 700,000 deaths each year(1, 2), telling us again, that fresh approaches are called for in managing and preventing infectious diseases in humans.

New Zealand is currently one of the best placed countries in the world to build a rich natural health product industry that could make a much bigger contribution to our future exports and GDP. Apart from our natural resources, fertile soils and hard-working farmers, we have an enviable track record of research and development in biological and agricultural sciences, and pharmaceutical company development. Many intelligent people who work within universities, crown research institutes, private laboratories and as R&D providers have contributed to building and supporting a range of companies making products from plants that are competitive and premium quality, and in demand from overseas markets. As with other crops such as avocados, fruit and nuts, returns per hectare from growing medicinal plants are relatively high, although initial establishment costs such as growing systems and processing facilities can be significant, and benefit from economies of scale.

Growing ginseng in New Zealand pine forests has been shown to produce a premium quality (high ginsenoside-containing) and potentially very lucrative crop(3, 4). Rising demand for medicinal mushrooms through research supporting their usefulness in conditions such as cancer, immune conditions, viruses and lung inflammation(5), suggests research into some of the diverse introduced and native fungal species we see growing in our native and planted forests, would also be worthwhile.

While some early commercial operations into growing crops such as ginseng, green tea, ginkgo, saffron and mānuka as sources of medicines has revealed many challenges, others focussed on these and other medicinal plant species, have succeeded, and demand is now often outstripping supply. Further opportunities exist with cultivating high quality and sustainably grown phytomedicines such as saffron, rhodiola, false unicorn root and golden seal, all of which demand high prices due to being endangered in the wild yet highly sought after for their medicinal properties.


A Call to Action:

Covid-19 has jolted the world, and caused a sudden shift in the way we used to do things, and how the future will look. Like other countries, New Zealand needs to respond to this as a matter of some urgency, by identifying and pursuing new opportunities that have become even more apparent since this virus jumped into humans.

Businesses themselves will of course continue to develop innovative products and pursue emerging export market opportunities. However, support from government to enable more research and the development of increased local raw material production would both help facilitate increased exports by this fast growing and healthy industry. This would also help regenerate rural economies, and provide new sources of employment to those severely impacted by Covid-19.

A working group of industry, science, Māori, farming and government representatives should be formed to further explore options, and some of the regional development and other government funds that are being allocated to support business development and employment initiatives during the Covid-19 pandemic, could perhaps be allocated to this. An action plan to support new initiatives to help New Zealand leverage some of these large opportunities, could include the following:

  1. Investment in research into phytomedicines as well as that involving drugs, for Covid-19 and as antibiotic alternatives or adjuncts.
  2. A stocktake and comprehensive survey of various weeds, native plants and fungi that could be propagated and harvested as a secondary income earner for the forestry industry.
  3. Research into medicinal plants including field trials on selected species, to learn more about their agronomy, optimal growing conditions and geographical locations, and quality plus commercialisation considerations.
  4. Research into the phytochemistry, pharmacology and agronomy of New Zealand native plants and fungi, and an integrated approach to enable these being able to make a greater contribution to the future health care of both local communities, as well as wellness needs of our future generations and tamariki.
  5. Support for private sector businesses engaged in researching and establishing export markets for innovative, value added natural health products made from locally grown raw materials.
  6. Funding for clinical trials into phytomedicines that have the potential to be both grown in New Zealand, and make a valuable pharmaco-economic contribution to future health care treatments.


Finally, in writing this I’ve been taken back to remembering one of the children’s books I used to read to my son a few years ago,Dinosaurs (and all that rubbish)” by Michael Foreman. The book describes how the dinosaurs have taken over the Earth, after it not being treated kindly by humans, and one piece of it reads:

“As the rubbish was cleared

Green shoots appeared,

Bursting through cracks

And climbing over old forgotten walls.

Telegraph poles and iron pylons

Vanished beneath trailing blossoms,

And a fresh new forest

Of flowers and trees spread

Like a smile around the world”.



Phil Rasmussen

28 April 2020



withania seedlings 2016



  2. Gerberding JL, First Opinion, 23 March, 2020.
  3. Chen W et al, Biomolecules 2020; 10(3):372.
  5. Chaturvedi VK et al, 3 Biotech. 2018 Aug; 8(8): 334.



Global panic has set in from the December 2019 outbreak of a new human form of coronavirus (SARS-CoV-2), responsible for causing the disease COVID-19 initially in China, and which has now become a pandemic as it spreads in multiple countries.

This virus is genetically closely related to the SARS-CoV-1 virus which first appeared in 2003, and is different to seasonal influenza. The mortality rate of COVID-19 is approximately 36 per 1,000 people, with highest rates in the elderly and those with pre-existing respiratory or cardiovascular disease, or diabetes. By comparison, the death rate from seasonal influenza is approximately 1 per 1,000 people (European Centre for Disease Prevention and Control (1).

As at the time of writing, at least 218,000 cases of COVID-19 and more than 8000 deaths have been reported globally, and numbers are increasing rapidly. No vaccine or proven drug treatment options are available, and panic buying in many countries has led to supermarket shelves been cleared of items such as toilet paper and hand sanitiser. Natural health products aimed at enhancing immunity, are also in high demand and supply shortages are becoming apparent.

It is therefore appropriate to start thinking about the various common herbs and spices, weeds and other plants available in our individual communities, that may be useful to support the need for greater ‘self care’ in the next few weeks or months.

This article will discuss some culinary herb and spice options, and will be followed by others on weeds and native plants, growing here in Aotearoa, New Zealand.


Part 1: Culinary spices and herbs:

Many well-known spices and herbs used in cooking have useful antimicrobial properties, and it is these in addition to their effects on the human palate, that made them very important and highly valued in early human trade. These include oregano, thyme, rosemary, ginger, garlic, onions, welsh onions, black mustard, cinnamon and blackseed.

While for the majority it is their antibacterial rather than antiviral actions that are most established, several seem to have effects that could be directly relevant to the prophylaxis or management of a COVID-19 infection.

While the COVID-19 situation is evolving rapidly and there is much not well understood, a large percentage of those who became severely ill or died from previous viral pandemics in 1918, 1957, 1968 and 2009, developed bacterial pneumonia, with Staph aureus and Strep pneumoniae being the most common bacterial pathogens (2). Evidence to date suggests that this virus is likely to be similar, and a significant proportion of SARS-1 and at least 10% of COVID-19 patients, develop such secondary bacterial infections in addition to infection with the virus itself (3).

These bacterial co-infections are associated with significant inflammation, and sometimes pneumonia and death. Pandemic viral infections make their development more likely, as viruses express bacterial adhesion receptors and can invoke an inflammatory response that can disturb the integrity of the respiratory tract’s normal physical barrier to bacteria (4). Recent studies in children also reveal complex interactions between viruses, the respiratory microbiome and the host’s immune response, which may have an impact on the pathogenesis and severity of respiratory virus infections (5).

While appropriate antibiotics can be life-saving and if available should be prescribed during serious bacterial lung infections and pneumonia, antibiotic resistance due to their overuse, and limited access to antibiotics for many, are seriously growing concerns for the human race. Therefore, herbs and spices that have traditional and/or scientific evidence of strong antibacterial activities, may be useful and should be considered. This is particularly likely to be the case, where their traditional use relates to conditions affecting the lungs or respiratory tract.

Some such culinary herbs and spices that spring to mind, are Garlic, Horseradish, Thyme and Oregano. These or other herbs traditionally used for congestion or infection of the lungs, may provide relief to some patients, and help lessen the risk of secondary bacterial infections and need for antibiotics or other drug-based medications.


Ginger (Zingiber officinale)

This is one of my favourites, for so many reasons. Much more than just a warming spice to add a bite to our food and smoothies, the rhizome and root of ginger has pronounced anti-inflammatory (6) and possibly some antiviral (7,8) properties, which may be useful.

High concentrations of a water extract of fresh but not dried ginger showed anti-viral activity against human respiratory syncytial virus in human respiratory tract cell lines, this activity being greatest when given before viral inoculation (9). A similar dose-related antiviral activity was measured in vitro against the avian influenza virus H9N2 (10).

Inhibition of Hepatitis C viral protease has been reported for both aqueous and methanol extracts of ginger (11). An Eqyptian clinical study found administration of a hydroethanolic extract to Hepatitis C patients decreased their viral load and improved liver function. These effects were enhanced when ginger was combined with blackseed (Nigella sativa) (12).

Zingiber montanum (Cassumuna ginger), a related Asian ginger species which is noxious in various countries, has been reported to more than halve the level of infectivity of the highly pathogenic avian influenza virus H5N1 in a cell-based assay (13).

Apart from potential antiviral effects, studies on animals suggest that modulation of the immune response to viral infections, may contribute to ginger’s beneficial effects (14, 15). One study for example, measured no inhibitory effect on the growth of influenza A virus for ginger root extract itself, but found it to produce activation of the macrophages leading to production of TNF-alpha (16).

While like other culinary herbs and spices specific anti-COVID-19 activity is unproven, there seems to be much to gain from preparing a hot drink by gently simmering a good few slices of the rhizome of this popular spice in a saucepan with the lid on it, then drinking this as a decoction. Particularly when stuck at home during an enforced winter lockdown!


Garlic (Allium sativum)

The reputation of garlic bulbs as an antimicrobial agent is strong, but this pertains mainly to antibacterial and antifungal activities, and the evidence it helps with viral infections such as colds and influenza, is mixed (17, 18).

One clinical trial in healthy volunteers found 90 days administration of an aged garlic extract to reduce the severity and symptoms, but not the frequency of colds and influenza (19).

Promising findings have however, been recently reported for a gold nanoparticle product made from garlic extract, as a potent inhibitor of the measles virus (20).

Like garlic, other Allium species such as onions, leek, shallot, scallion, and chives also show evidence of useful antimicrobial properties, and contain a plethora of bioactive compounds such as organosulfur compounds, polyphenols, saponins, fructans, and fructo-oligosaccharides (21). Green tops of Welsh onions (Allium fistulosum) for example, contain a fructan which showed inhibitory effects on replication of influenza A and enhanced antibody production against this virus in mice (22).

Garlic extracts show activity against Streptococcus pneumoniae and Klebsiella pneumoniae (23). Garlic’s antimicrobial activities are largely due to sulphurous compounds such as allicin (diallylthiosulfinate), a volatile compound produced when garlic is crushed. German researchers have shown allicin vapour to inhibit the growth of a range of lung pathogenic bacteria, including multi-drug resistant strains (24).

This suggests that frequent direct inhalation of crushed garlic may be useful to help combat bacterial lung infections, and could be a useful adjunct with oral antibiotics, where bacterial co-infection exists or is suspected.


Holy Basil (Tulsi) (Ocimum tenuiflorum, O sanctum) and Sweet Basil (Ocimum basilicum)

A popular aromatic herb used in cooking particularly by the Indian community, the leaves of Holy Basil or Ocimum tenuiflorum as well as other Ocimum species including the related so-called European or sweet Basil (Ocimum basilicum), are revered for their medicinal properties. Both these and other Ocimum species (but particularly Holy Basil) also contain the triterpenoid compound ursolic acid, which exhibits strong antiviral activity against a range of viruses such as herpes simplex, adenoviruses, rotavirus, coxsackievirus and enterovirus (25, 26).

A crude extract and terpenoid isolated from Holy Basil leaves has shown promising antiviral properties against H9N2 virus (27). In vitro activity against the HIV virus, has also been reported for the related Ocimum gratissimum (28).

Recent studies have also found an extract of sweet basil leaves to inhibit attachment and entry of the Zika virus into the host cell (29). Evidence of possible neuraminidase inhibitory activity against the H1N1 swine flu virus for the flavonoid compound apigenin, extracted from Holy Basil and found in a range of other medicinal plants, has also been reported (30).

While becoming out of season now in New Zealand, for those in warmer climates or with greenhouse growing options, planting lots of these two easy to grow herbs now, may pay dividends beyond their yummy flavours in the future.


Blackseed (Nigella sativa) or Ketza (black cumin)

This is a highly regarded traditional remedy used by many Asian, Middle Eastern and northern Africa ethnic groups in cooking and for a wide range of health issues, including to enhance immunity and to treat diarrhoea and various types of infections (31).

Protection against murine cytomegalovirus has been reported for blackseed oil (32). Eqyptian studies found blackseed administration to significantly reduce the viral load in patients with Hepatitis C (33), and to inhibit replication of this notoriously resilient virus (34). Six weeks administration of a combination of blackseed with echinacea also enhanced the immune response after vaccination against the H9N2 avian influenza virus, and reduced the pathogenicity of infection in stressed chickens (35).


Cinnamon (Cinnamonum zeylanicum)

The bark from various Cinnamonum species found in Sri Lanka, Indonesia and now cultivated in other Asian countries, has been traded for more than 2000 years, and was imported by Arabs to Eqypt, Venice and Europe, where it was used to preserve meats as well as for flavour. Control of the Cinnamon trade was a key factor in Portuguese (then Dutch) control of Sri Lanka, in the 16th century.

Potential benefits in fever management have been reported using an influenza virus infection model in mice (36), and antiviral effects against H1N1 Influenza A and herpes simplex viruses, as well as antibacterial effects against Staph aureus and Strep pneumoniae, shown for a blend of Cinnamomum zeylanicum, Daucus carota (wild carrot), Eucalyptus globulus (eucalyptus) and Rosmarinus officinale (rosemary) essential oils (37). A nanoparticular form of Cinnamomum cassia also exhibited promising activity against the H7N3 Influenza A virus (38). Trans-cinnamaldehyde, a major constituent of cinnamon essential oil exhibits in vitro antiviral activity against influenza A/PR 8 virus, and when given by nasal inhalation increased the survival rates of mice infected with a respiratory virus (39).

Cinnamon, its essential oil and its key constituents cinnamaldehyde and cinnamic acid also possesses strong antibacterial activity against a range of pathogenic bacteria (40), so incorporating some of this spice into your winter wellness warming beverage or mulled wine could be a good move.


Horseradish (Armoracia rusticana)

Not just a sought after culinary sauce, the roots of this strong and distinctive plant, have a long tradition of use particularly in Europe, for the treatment of bronchial infections.

Isothiocyanates from horseradish root exhibit broad spectrum antibacterial activity in vitro (41), and a mixture of horseradish when mixed with Nasturtium (Tropaelum majus), showed good activity particularly against Haemophilis influenzae, and intermediate activity against Staph aureus, Strep pneumoniae, Klebsiella pneumoniae and Strep pyogenes (42). Some evidence of prophylaxis against the H3N2 influenza virus has been reported in animal studies (43), though as with many of the herbs and spices I have mentioned, large doses are likely to be required.

While not widely grown here in New Zealand, it isn’t difficult to cultivate, and in fact can become ‘weedy’, not unlike how it grows in many locations in the U.K.

Other spices that may be useful, include Turmeric (Curcuma longa), and Black mustard (Brassica juncea). Both water and ethanolic extracts of black mustard have been reported by Korean researchers to exhibit in vitro activity against influenza virus A/H1N1 (44,45). Researchers in Thailand recently screened some Asian medicinal plant extracts and found ethanolic extracts of turmeric root as well as the leaf of guava (Psidium guajava), to have good in vitro activity against the H5N1 influenza virus (46).

While COVID-19 is a highly virulent and very challenging virus to combat and at the current time we have no research establishing the clinical efficacy of any of the herbs and spices I have mentioned, there is an urgent need to take an interest in this subject and what dietary interventions may perhaps assist, with infection prophylaxis at least. Similarly there are a number of weeds and native plants growing in our beautiful country that may also be helpful, and which I will discuss in subsequent postings.

I’m not lucky enough to be living in a bush area where the large, soft-leafed NZ native plant Rangiora (Brachyglottis repandra, “Bushman’s Friend”) is endemic and so if we run out of toilet paper will need to invoke other methods, but I’m feeling OK about having everyday plants on hand to take as teas or inhalations, should I or my family need to in the coming months.



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Optimising Immunity to Protect against Coronaviruses

The outbreak of a new human form of coronavirus (Wuhan novel coronavirus, 2019-nCoV) in December 2019 in the city of Wuhan in China, is spreading fear and alarm around the world.

Around 56 million people in China have been under lockdown since Chinese New Year, and the Chinese government has just completed the fast-tracked building of the first of two new hospitals in Wuhan, to help cope with a rapidly growing number of cases. As at Monday 3rd February, 20,438 confirmed cases have been reported across all regions in China as human to human transmission occurs, and 425 people have died following infection with the virus, 414 of which were in Hubei province where Wuhan is located. Cases have now been reported in at least 25 other countries, though only one death outside of China has been reported to date.

As with other serious virus outbreaks that have emerged over the past 45 years such as Ebola virus, Bird Flu (H5N1) and Swine Flu (H1N1) virus, this coronavirus seems to have originated in another animal species (probably a bat), and jumped the barrier to be able to replicate itself in humans.

China is now more prepared than it was back in 2002 when the SARS (Sudden Acute Respiratory Syndrome) virus emerged, killing 774 of the 8090 people reportedly infected. Also, while it is relatively early days, indications are that the death rate from 2019-CoV will be less than that of SARS, at around 2-3% of diagnosed cases, versus around 10% for SARS. However, like all viruses 2019-nCoV is likely to continue to mutate rapidly, and new more pathogenic forms are possible.


The Coronavirus

Coronaviruses are a fairly large family of viruses that cause illness ranging from the common cold (responsible for 15-30% of cases), to more severe diseases such as Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). They typically infect the respiratory tract, though the gut can also be affected.

Human to human transmission of 2019-nCoV seems to be relatively easy, though we are still learning about the various means through which this can occur. A 7-14-day incubation period seems to occur before symptoms begin to show, although even asymptomatic cases can be infectious,

Most 2019-nCoV patients initially hospitalised in Wuhan had fever at the onset of symptoms, and well as dyspnoea (shortness of breath) and a cough. Myalgia (muscle pain) or fatigue also seem to be common symptoms. The main cause of death is from pneumonia and acute respiratory distress syndrome(1).


Treatment Options

There are no proven effective antiviral drug treatments for coronavirus infections, and our biggest protection against this new virus or others that may come our way, relies largely upon the execution of good Public Health measures. Restricting travel, wearing masks, washing hands frequently, the use of sanitising agents and the isolation of those with suspected infections, is the best current approach to help reduce the risk of spread to others.

In considering the nature of the virus and what is known about it so far, there would appear to be a number of possible pharmacotherapy (drug and/or herbal) approaches, namely:

  1. Enhancing immunity to help protect against infection, or if it takes hold, to improve the body’s ability to fight it.
  2. Antiviral actions to specifically inhibit the ability of 2019-nCoV to take hold and replicate.
  3. Lung and respiratory tract protective, healing and anti-inflammatory agents.
  4. Other agents such as febrifuges and systemic anti-inflammatories, to help reduce acute symptoms in some cases.

Since this virus hit the headlines a plethora of articles and social media posts promoting a whole range of natural including herbal treatments has appeared, although the quality of many of these leaves much to be desired.

Just as drug developers have found it challenging to make drugs that have clinically significant antiviral actions, the evidence for herbal remedies having the same, is slim. I am not saying they don’t exist, because I’m sure they do.

However, claiming an antiviral action of a herbal preparation based upon an in vitro antiviral activity shown against a virus completely unrelated to 2019-nCoV, by an individual phytochemical found in relatively low amounts in a whole herb, and usually about which little if anything is known on its bioavailability (ability to be absorbed from the gut after oral administration and distributed to the area in the body where it needs to act), is a very far reach.

A more likely efficacious and evidence-based approach to incorporating plant-based products to help reduce the potential impact of this new virus on human health, is therefore to focus on enhancing immunity. Herbs that help foster greater immunity or that protect or help heal the respiratory tract from the acute inflammation, shortness of breath, pneumonia and respiratory failure that are main causes of serious illness and death, are worthy of consideration.


Optimising immunity

As with all infectious diseases, the level of pre-existing immunity to the microbial pathogen, is a key factor known to influence the susceptibility to and severity of an infection, and immunocompromised patients are more vulnerable to viral infections. The largest factor in immunity to influenza and coronaviruses seems to be serum antibodies induced by prior infection or vaccination, which impart a strong and disease specific host resistance to the virus. However, it will take many months or even years to develop a vaccine, and even then, the virus may mutate further by that time.

Plants have much to offer in terms of optimising immunity in humans, and a healthy vegetable and fruit rich diet, is increasingly linked with favourable influences on the gut microbiome and immune function(2). Many plant and mushroom derived preparations have been shown to help enhance human innate immunity (resistance) to different viral and bacterial pathogens, and a full review of these is not possible here. However, I consider Echinacea (Purple coneflower) one of the most promising from both a traditional as well as evidence-based perspective.



Echinacea was an important traditional medicinal herb to Native Americans, and different species were used to treat animal bites and a wide range of infectious and inflammatory conditions(3,4). Early European settlers to the Midwest adopted Echinacea purpurea and Echinacea angustifolia as a treatment for wounds and glandular inflammation, and it was a preferred treatment by many clinicians for infections until discovery of penicillin. There are now more than 1200 scientific papers published on it, and its principle application over the last 50 years has largely been as a prophylactic or treatment for colds and influenza.

Several clinical trials have shown beneficial effects of echinacea during the treatment of colds and influenza, although others have had less favourable outcomes. However, evaluation of these is complicated by the use of a diverse range of product types, plant part(s) and doses used.

Immune enhancement and modulation, and anti-inflammatory effects, are principal actions of echinacea, and numerous studies have reported immunological changes associated with echinacea root usage. Key outcomes seem to be increased numbers of circulating white blood cells, monocytes, neutrophils and natural killer (NK) cells, and the abilities of these immune cells to engulf and inactivate harmful microbes or carcinogens. This enhancement of the non-specific immune response, is thought to improve the body’s ability to maintain immunosurveillance against a variety of potential viral or bacterial pathogens or spontaneous-developing tumours.

Canadian researchers found that normal mice given Echinacea purpurea root had significantly prolonged life spans versus non-immunized mice(5). NK cells were also elevated in leukaemic mice receiving echinacea in their diet versus those who didn’t(6). Japanese researchers found Echinacea purpurea to have a suppressive effect on spontaneously occurring leukaemia caused by a murine leukaemia virus, an effect related to enhancement of immune systems(7).

Stress is known to reduce immunity, and echinacea has shown beneficial effects on stress-induced immunosuppression by increasing splenocyte proliferation and NK cell activity, while modulating blood levels of inflammatory cytokines(8).

Secondary or co-existing bacterial infections are also a common cause of pneumonia and death in patients with viral infections of the respiratory tract, and have been reported in approximately 10% of 2019-nCoV hospitalised patients(1). Viral infections can express bacterial adhesion receptors, and the virus-induced inflammatory response can also disturb the integrity of the physical barrier to bacteria. Evidence suggesting echinacea may prevent virus-induced bacterial adhesion to cell membranes, and moderate an excessive inflammatory response (cytokine storm) sometimes seen with pandemic forms of viruses(9,10), may therefore contribute to improved host resistance against pathogenic viral infections.

Alkylamides (alkamides), found in highest concentrations in the root, are now regarded as major bioavailable and active immunomodulatory components in oral forms of echinacea(11). However, microbes known as endophytes that live in close association with echinacea, also exhibit strong antibacterial effects against respiratory pathogenic bacteria such as Klebsiella pneumonia, Burkholderia cepacia and Acinetobacter baumannii(12-14). Recent research also suggests that inulin-type fructans found in echinacea, which are prebiotic compounds that promote a health microbiome, may also contribute to beneficial immunomodulatory effects(15).

In summary, while the situation in China and elsewhere will continue to evolve rapidly over the coming weeks, given its seriousness and the limitations of drug treatment options at this point, herbal options such as echinacea to help optimise our immune system’s resistance to 2019-nCoV or other viruses that will continue to come our way, should be considered.



  1. Huang C et al, Lancet 2020 Jan 24; epub ahead of print.
  2. Tomova A et al, Front Nutr. 2019 Apr 17;6:47.
  3. Felter HW. The Eclectic Materia Medica, Pharmacology and Therapeutics. Eclectic Medical Publications, Oregon, 1922.
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  5. Brouseau M, Miller SC, Biogerontology. 2005;6(3):157-63.
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  7. Hayashi I et al, Nihon Rinsho Meneki Gakkai Kaishi. 2001;24(1):10-20.
  8. Park S et al, J Med Food. 2018; 21(3):261-268.
  9. Rasmussen PL, Phytotherapy in an Influenza Pandemic: Swine Flu. Phytonews 32, 2009, June. Published by Phytomed Medicinal Herbs Ltd, Auckland, New Zealand. ISSN 1175-0251.
  10. Vimalanathan S et al, Virus Res. 2017; 2(233):51-59.
  11. Mudge E et al, J Agric Food Chem. 2011; 59(15):8086-94.
  12. Haron MH et al, Planta Med 2016; 82(14):1258-1265.
  13. Presta L et al, Res Microbiol 2017; 168(3):293-305.
  14. Chielleni C et al, Microbiol Res. 2017 Mar;196:34-43.
  15. Dobrange E et al, 2019 Oct 16;9(10). pii: E615.


The bushfires in Australia have worsened since I wrote about them a couple of weeks ago. Frequent exposures to hazy skies containing tiny airborne pollutants that are damaging to our lungs, have been incurred by millions of Australians, and also by many New Zealanders due to drift across the Tasman. Smoke from the Australian fires has also travelled to Argentina and across to the Atlantic, a stark reminder of how climatic events in one part of the world can have significant impacts on those living in completely different continents.

In addition to mucilaginous (polysaccharide hydrocolloid rich) and expectorant herbs such as Marshmallow (Althaea officinalis), Mullein (Verbascum thapsus) and the New Zealand native Hoheria (Hoheria populnea), evidence suggests that other herbal medicines can be beneficial for those forced to live or work in environments where exposure to smoke or fine-particulate matter containing and toxic haze from bush or forest fires, is unavoidable. Herbs with protective actions against airborne lung damaging and potentially carcinogenic compounds, are of particular interest.

One of the most promising herbs in this regard, is Elecampane (Inula helenium), the roots of which have long been traditionally used in treatments for coughs, chest infections, asthma and other lung conditions. Elecampane is an anti-inflammatory, antimicrobial and antioxidant herb, and contains various constituents exhibiting lung protective effects.

Research showing in vitro activity by elecampane against various forms of human cancer cell lines was first reported in 2002(1), and several further investigations into anticancer properties of elecampane and other Inula species, have produced favourable results(2-8). While having antitumour activity against cancer cells, no harmful effects have been measured on normal cells(3).

The sesquiterpene lactones alantolactone and isoalantolactone, key sesquiterpene lactone constituents in elecampane roots, undoubtedly contribute to these effects, having inhibitory effects against human lung, breast, prostate, colon and pancreatic cancer cells through a range of different mechanisms(10-13). Alantolactone also increases the sensitivity of lung cancer cells to the effects of the chemotherapy drugs doxorubicin and gemcitabine(9,10), suggesting a possible role as adjunctive therapy.

Isoalantolactone has also been shown to have marked anti-inflammatory effects and to reduce the extent of lung injury following exposure to lung damaging compounds in animal studies. Beneficial effects included suppression of pulmonary pathological changes, neutrophil infiltration, pulmonary permeability, and pro-inflammatory cytokine expression(14).

However, isoalantolactone and alantolactone seem to have low bioavailability when given orally to rats, possibly due to poor stability in gastrointestinal fluids and being subject to significant degradation by the liver after absorption through the so-called “first pass effect”(15,16). As such, alternative means of administration of elecampane apart from the usual oral route, particularly when the lungs are the target organ, are worth considering.

Many traditional applications of herbal medicine including Maori Medicine (Rongoā Māori), Ayurvedic, Chinese and European herbal medicine, utilised inhalation through the lungs as a popular method of administration. This pulmonary route of administration through inhalation or sprays, is also used widely in modern drug-based medicine as a means of treating conditions such as asthma or sore throats, or as a way to deliver drugs to the general blood circulation and treat other systemic conditions. Well-known examples include the pronounced bronchodilatory or anti-inflammatory effects through inhaling bronchodilatory or anti-inflammatory asthma drugs, relaxant and calming effects through inhalation of essential oil-rich preparations such as lavender or chamomile, and the well-known effects through inhaling preparations of plants such as cannabis and tobacco. The high permeability and large absorptive surface area of the lung alveolar epithelium, its good blood supply, the rapid onset of action and capacity for overcoming first-pass metabolism, can provide significant advantages of a pulmonary rather than oral route of administration(17-18).

With increasing evidence that acute or chronic environmental or occupational exposure to airborne carcinogens or lung-damaging compounds can have serious effects on human health, not only in an era of increasing bushfires but also amongst farmers handling pesticides, firefighters, painters and others working in dusty environments, the possible application of chemo-preventive and lung protecting herbs such as elecampane through the pulmonary route as an inhalation or spray, deserves more attention.

inula photo


  1. Konishi T et al, Biol Pharm Bull 25(10):1370-1372, 2002.
  2. Spiridonov NA et al, Phytotherapy Res 19(5): 428-432, 2005.
  3. Dorn DC et al, Phytother Res. 2006 Nov;20(11):970-80.
  4. Wang GW et al, Expert Opin Investig Drugs. 2014 Mar;23(3):317-45
  5. Chun J et al, Phytother Res. 2018 Dec;32(12):2501-2509.
  6. Koc K et al, J Cancer Res Ther. 2018 Apr-Jun;14(3):658-661
  7. Zhang B et al, Mol Med Rep. 2018 Apr;17(4):5440-5448.
  8. Bar-Shalom R et al, Front Oncol. 2019 Apr 10;9:227
  9. Wang J, et al. Int J Mol Med. 2019. Sep;44(3):1026-1038
  10. Maryam A et al, Sci Rep. 2017 Jul 24;7(1):6242
  11. He R et al, Toxicol Appl Pharmacol. 2018 Oct 1;356:159-171.
  12. Liu J et al, J Food Biochem. 2019 Sep;43(9):e12972.
  13. Wang J et al, Int J Mol Med. 2019 Sep;44(3):1026-103
  14. Ding YH et al, Acta Pharmacol Sin. 2019 Jan; 40(1): 64–74.
  15. Lee JY, et al. Biopharm Drug Dispos. 2016. Apr;37(3):156-67
  16. Xu R et al, Eur J Drug Metab Pharmacokinet. 2019 Apr;44(2):295-303
  17. Patil JS, Sarasija S.Lung India. 2012 Jan;29(1):44-9.
  18. Gandhimathi C, 2015 et al. J Nanosci Nanotechnol



Bushfires have been burning across many parts of Australia in recent weeks, particularly in the most populated state of New South Wales, and more recently Victoria.  Catastrophic fire conditions have existed, with flames being fanned across the country by high winds, above 40°C temperatures, low humidity and long-term dryness in the bush. These fires are unprecedented and deadly, and many lives and homes have been lost. An area bigger than Belgium has already been burned, despite the warmest summer months not yet arrived.

The frequency and severity of bushfires in Australia will continue to increase with global warming, as they also will in New Zealand, California and other parts of the world.

Australian bushfires tend to burn for weeks on end across large areas of land, and this often sends smoke over populated areas. Residents of Sydney have endured smoke for weeks, and when I stood on the tarmac of Sydney airport recently, it was impossible to avoid the smokey smell despite official announcements saying there was nothing to worry about. Also the haze that seemed to envelop the whole city as the plane came in to land, causing poor visibility and making driving a dangerous pursuit.  Millions of people in Sydney and other parts of N.S.W. and Australia, have been blanketed by and frequently exposed to bushfire smoke in recent weeks.


Effects on lung health:

Exposure to smoke is obviously not good for human or animal health, and the links between cigarette smoking, lung cancer and emphysema, are well established.

Harmful gases in smoke from burning bush include carbon monoxide, carbon dioxide and nitrogen oxide, all of which are present in cigarette smoke and more prevalent nearer to a fire. However, most danger lies in ultrafine particles known and measured globally as particulate matter PM2.5 (smaller than 2.5 micrometres in diameter). These are invisible to the human eye, cause haziness in the air and can travel vast distances on the wind. They are often coated in toxic chemicals such as lead, and are most worrying because their tiny size means they are able to penetrate deep into the lungs.

Recent PM2.5 readings in Sydney have reported levels as high as 734 micrograms – the equivalent of smoking about 37 cigarettes a day. Firefighters and those living closer to blazes, have been and are being exposed to much higher levels, according to a director of the Fire Centre Research Hub at the University of Tasmania, Prof David Bowman (1).

Australian Paramedics have treated hundreds of people for breathing problems, and there have been increased hospital admissions for asthma and breathing difficulties. Most sensitive are children, the elderly and smokers, while those with asthma, heart and lung problems have experienced increased symptoms such as chest tightness and difficulty breathing. If the smoke lingers, then harmful gases and PM2.5 particles could eventually have the same damaging effects on the lungs as cigarettes.

These types of exposures of millions of people to smoke inhalation from bush or forest fires, is clearly already a major public health concern. However, as with most health concerns, individual action and responsibility, also belongs to each of us.


Herbal support:

So what can Australians and anyone else subject to significant or chronic exposure to smoke from bush or industrial fires do to reduce the harmful effects of this to their health, apart from stay indoors with the windows shut, wear masks that experts say do little to prevent fine particle inhalation, or simply panic?

Like most people I am angry and concerned about climate change, and don’t have many answers to offer. However, the impact that these bushfires are having on the Australian people is absolutely enormous, and it is therefore appropriate to review evidence suggesting that certain plant extracts may be usefully taken or inhaled by those forced to incur either acute or longer term ongoing exposure to smoke.

I’ve previously mentioned some of these in my September 2016 and November 2018 blogs in relation to the Haze season in Singapore, and high levels of airborne pollution in downtown Auckland. They include the herbs Marshmallow, Mullein, Elecampane, White horehound, Horseradish, Nasturtium, Ribwort, Hyssop and the New Zealand native plant Hoheria. In this and the next couple of blogs, I will further explore the relevant traditional use and pharmacology of each of these herbs in more detail, as being potentially useful when inhaled or ingested to help protect our lungs and overall health against the numerous damaging effects of bushfire smoke and other airborne pollutants.


Expectorants & mucous membrane tonics:

With smokers and others exposed to airborne pollutants on a regular basis, a cough is the body’s natural reflex to expel unwanted substances from the lungs. Critical to the lungs defence system, are the millions of tiny hairlike structures known as cilia lining our lungs, which beat in waves and whose natural function is to expel mucus and potentially harmful particles or gases. In medicine, expectorants are drugs and herbal preparations which have the ability to speed up and enhance this natural elimination and protective process, and their inclusion in most cough medicines, is well known.

Marshmallow (Althaea officinalis) root is no longer included in marshmallow confectionary products sold today, but this plant is still commonly used as an expectorant and for bronchial congestion, by herbal practitioners. Good quality marshmallow root contains at least 5-10% of mucilaginous polysaccharides (known as ‘mucilages’ to most herbalists), which form a protective and soothing layer on inflamed or damaged mucous membranes and human epithelia (2). German researchers have measured an increase in cell viability, cell vitality and proliferation, following treatment of human naso-pharyngeal epithelial cells with marshmallow extract (3).

Another useful mucilaginous herb regarded as a tonic for respiratory tract mucous membranes, is Ribwort (Plantago lanceolata). The leaves of this common plant when harvested and prepared in the optimal way and taken in sufficient doses, support the cilia’s protective barrier effects by nurturing the delicate mucous membranes of the upper nasal passage. Like Marshmallow and leaves or bark of the sweet tasting and mucilaginous New Zealand native plant Hoheria (Hoheria populnea), it has an expectorant and cleansing effect on the upper respiratory tract. These and other herbal expectorants, can thus be helpful, to help facilitate the bodies own natural defence system designed to keep harmful particles and gases, out of our lungs.

sydney haze 20191206_192329_resized


  1. Davey Melissa, Australia faces ‘massive’ rethink to prepare for long-term bushfires and air pollution. The Guardian, 15 Dec 2019.
  2. Schmidgall J et al, Int J Biol Macromolecules 10, 217-225, 2002.
  3. Deters A et al, J Ethnopharmacol 127(1):62-69, Jan 8, 2010.

photo sydney haze


The subject of mental health unwellness in children and young people has been prominent in the New Zealand media in recent weeks, with huge cause.

Globally suicide is one of the top three causes of death in young people aged 15-19, globally(1). New Zealand has the highest suicide rate for 10-14 and 15-19 year olds out of 19 developed countries. These alarming figures were revealed in February this year through a study by the British healthcare think tank Nuffield Trust which compared UK’s record on adolescent health and wellbeing to 18 other developed, wealthy countries(2,3).

A 2017 University of Auckland study published in the Australian and New Zealand Journal of Psychiatry, found nearly one in 20 high school students (4.5%) reported attempted suicide, while 7.9% had repeatedly self-harmed over a 12 month period. Students from poor families were nearly three times more likely to try to take their own lives(4). Rates in rainbow youth, and young Māori men, are also higher than for others(5,6).

Reasons for these alarming statistics are multiple, but the fact that millennials and increasingly younger people are living a significant part of their lives online particularly on social networking and gaming, is undoubtedly contributory(7).

We live in a country where our culture and attitudes to depression, have historically been based too much on the ‘buck up and get on with it’ approach. However, these statistics and also the ‘Blam Blam Blam’ song of the same name released in 1981, demonstrate that the comment by former Prime Minister Robert Muldoon ‘There is no Depression in New Zealand’, has long been disproven.

The government is currently looking at how it can improve suicide prevention, and the increased media coverage of this issue is welcome. Early recognition and diagnosis, adults being more open to talking to young people about suicide and depression, and fostering a society where more of a sense of purpose can be gained by young people along their journey through youthhood and into adulthood, are critical needs.

Antidepressant drugs have saved countless lives since their inception in the late 1950s, despite some limitations. They don’t always work; adverse effects can be unpleasant and contribute to a very low compliance rate, and without addressing contributory factors, their long-term efficacy is often limited.

Herbal medicines have been used by different cultures for depression since time immemorial, although different terminologies were and still are often applied to this, and a definitive diagnosis according to DSM criteria obviously wasn’t made!

St John’s Wort (Hypericum perforatum) is of course the herb best known to western medical herbalists as an antidepressant, and there are now more than 2,000 peer-reviewed publications on this herb, including more than 30 clinical trials showing it to be as effective as antidepressant drugs for the treatment of mild to moderate depression(8). Its use increased dramatically from 1996 following publication of a favourable meta-analysis of clinical trials published in the British Medical Journal, and while usage reduced at least for a time from 2000 following reports of drug interactions and safety concerns, St John’s wort preparations are widely available ‘over the counter’ in New Zealand and Australia.

While this herb has certainly helped herbal medicine to be taken more seriously by English speaking populations, the self-medication of St John’s Wort in major depression is not necessarily the best approach. There are many more herbs that can also be useful in young people prone to depression, where the complexities of the condition are best suited to an overarching treatment plan overseen by suitably trained health practitioners. This is particularly so given New Zealand’s woeful record in preventing teenage suicide.

Depression frequently coexists with intense anxiety, in addition to those confounding socio-economic and cultural factors, such as poverty and too much online time. The pressure to succeed and worries about the environment and future contribute to an unhealthily high level and type of stress in young people. These factors can manifest as generalised anxiety disorder, sleep issues and over time result in feelings of low self-esteem and depression.

Herbal medicine has much more than St John’s wort to offer for young people with, or prone to, depression. As anxiolytics (anti-anxiety agents), they are much safer interventions than drugs such as benzodiazepines, and there are many herbal adaptogens (stress protectors) that can additionally help insulate young minds against the effects of prolonged or acute stress(9).

An example of how a herbal practitioner-directed treatment approach can help, was shown through a clinical trial undertaken in China between 2009 and 2013. This investigated the effects of individualised treatments with herbal medicine in a group of 146 severely depressed patients admitted to hospital(10). All patients continued to receive treatment with a range of antidepressant and other psychotropic drugs, and half of them took various additional herbal medicines that were individualised to their situation by traditional Chinese medicine practitioners.

Patients who received adjunctive herbal medicines during their average 28 day hospital stay, were 2.1 times more likely to achieve a clinical response (according to the validated Hamilton Rating Scale for Depression), & 5.8 times more likely to achieve remission, than those who received drug treatment only(10). Concomitant Herbal medicine use was also associated with fewer incidences of physical tiredness, headache, palpitation, dry mouth and constipation, although digestive discomfort was more often reported.

Against the background of alarming figures about mental health and particularly teenage suicide, governments should take a serious look at the potential for Herbal Medicine practitioners to help reduce these statistics and save lives. A plethora of natural health products aimed at the management of anxiety and depression are now directly available through pharmacies and health food stores. However, young people experiencing mental health challenges and who are clearly at an unacceptable risk of suicide, warrant a much more personal, integrative and professional approach to their particular situation. Given the seriousness of this issue facing so many of our young people, the need for regulatory and funding systems that support the provision of much greater access to the personalised interventions and individualised treatments that well-trained medical herbalists can provide, is now urgently needed.



  1. World Health Organization (2014a) ‘Adolescent health epidemiology’
  1. NZ Herald, Feb 26, 2019, NZ Ranks bottom of developed countries on youth mortality rates.
  3. Chan S et al, Aust N Z J Psychiatry. 2018 Apr;52(4):349-356
  5. NZ Herald, 2 Aug, 2017, Break the silence: Rainbow suicide rate five times higher than mainstream.
  6. NZ Herald, Aug 17, 2019. Anxious millennials reach out for help.
  7. Rasmussen PL, Feb 2018. St Johns Wort: Safety concerns in clinical practice. Practitioner Webinar, Phytomed Medicinal Herbs Ltd, Auckland, NZ.
  8. Rasmussen PL, Feb 3, 2017. Why Herbs should be the first choice of treatment for acute anxiety.
  9. Liu LY et al, J Affect Disord 2015; 170:71-77. 


Sustainability. A much used word these days, it is generally defined as living in a way that meets the present generation’s needs without compromising the ability of future generations to meet their’s. The Maori word Kaitiakitanga, is a better term however. Kaitiakitanga is based on the deeper concept that people are all closely connected to and part of the land and nature, and puts the onus of guardianship and protection on all of us to care for all aspects of our environment.

Something that most consumers of natural health products don’t know or think enough about, is where the plants that provide the raw materials for these products, actually come from.

Tea and coffee drinkers increasingly take an interest in the country of origin, the plantation business model (profit-sharing or not), Fairtrade and organic or non-organic status of the leaves or beans that produce their daily drinks. This is because more of us are now making the connections between sustainability, ethics, quality and health. Not just our own health, but that of other people and the environment.

What few people realise is that global medicinal herb trading is similar to that for other commodities, in that most medicinal herbs procured globally come from people living in rural communities in countries where wage expectations are relatively low. As with commodity crops such as tea, coffee, cocoa and cotton, the international herb and spice trade and supply chain is driven largely by the abilities of those in the final rather than earlier stages of the supply chain to make a profit.

As a teenager, I was emotionally moved and became resolved to try and help make the world a better place, after reading “How the Other Half Dies”, by Susan George. Susan’s 1976 book, provided startling information about Third World poverty, underdevelopment and debt, and the contribution of corporate greed and politics to a world in which the gap between wealthy and poor countries, is far too wide.

The issues raised in the book are even more pertinent today, with the additional onset of Climate Change due to human practices, beginning to majorly impact our ability to produce enough food and ensure people – particularly in poorer countries – have access to healthy food and medicines.

Plants are used as the primary form of medicine by around 80% of the world’s population, but the over-influence of price on procurement practices adopted by most companies, means that quality and Kaitiakitanga are all too often compromised. This affects the likelihood that natural health products consumed by end users are in fact therapeutic, rather than subtherapeutic or contaminated.

Product parameters such as the plant part and extract type, the amount used and dose recommendations made, obviously have a significant impact on why some herbal medicines work and others don’t. However, where plants come from and how they are handled along the way, can also have significant impacts on finished product quality and efficacy.

There are numerous variables and stages involved in medicinal herb supply chains, and all of these are important. If the processes in place for these are good, in that people are receiving a living wage and paying a high level of care and attention to each stage (including growing, harvesting, washing, drying or storing the raw plant materials), the finished product will more likely be good.

Unfortunately there are a lot of unscrupulous practices that sometimes take place within the herb industry–some of it intentional, some of it not. These include adulteration, incorrect species identification, whether workers have washed their hands or have access to clean water, what the collection bags were previously used for, whether the plants were harvested in the rain or sun, and processed quickly or left in a pile in a tarp for a few days until workers had time to process them. Programmes to control use of agrichemicals are also either limited or non-existent in most poorer countries.

Small-scale farmers and workers involved in the majority of medicinal herb production are amongst the most marginalized groups globally. Through Fairtrade people can lift themselves out of poverty to maintain successful livelihoods. Also, by getting more of the herbs we use grown locally, and supporting communities and companies who are trying to build capabilities and provide meaningful jobs in this sector to our own lower socio-economic communities, is a powerful ethical and quality-driven approach, which promotes Kaitiakitanga.

Quality and Ethics are intrinsically linked, just as Quality and Efficacy are. Through prioritisation of ethical behaviours, all of the people involved in supply become motivated and concerned with quality. And the natural health products we take, are then more likely to genuinely promote both personal wellness, and that of the planet and its future.



New Zealand plants are unique, and amongst the best in the world. As an island nation situated a long way away from most other places, in the 55 million years since New Zealand separated from Gondwanaland, its native plants had a long time to evolve before humans arrived, and it’s therefore not surprising that many have some special properties.

Aside from indigenous species, numerous other plants also seem to have special characteristics when grown in the New Zealand environment, and we are fortunate to live in a country where such a wide variety of plants can be grown relatively easily.

Reasons for this are many, but probably include the relative youth of our landmass, the richness of our soils carved from volcanoes, rainforests and other inputs from nature, and our diverse geography and microclimates. There are few countries in the world where one can be sunbathing on the beach in the morning, and skiing in cold alpine temperatures a few hour’s drive away, in the afternoon.

The bioactive and medicinally active compounds in plants, are known in plant physiology and phyto-pharmacology as secondary metabolites. These include many different classes of chemical compounds such as alkaloids, flavonoids, essential oils and phenolic acids, whose functions within the plant are mainly to protect it against harmful influences or predators.

Plants growing in a stressful drought environment will produce higher levels of secondary metabolites than plants which are less stressed. Next time you are out in the bush, look out for kawakawa plants and you may notice that many of the heart shaped leaves contain lots of holes, courtesy of the kawakawa looper moth caterpiller. This is a good example of a plant thought to have greater medicinal properties from secondary metabolites, produced as a defense mechanism against the caterpillars.

One reason why so many plants grow so quickly and well in New Zealand, is thought to be attributable to the hole in the ozone layer in the atmosphere above us. In response to high UV-B light, New Zealand plants have to put greater energies into producing secondary metabolite compounds to protect themselves, many of which have medicinal properties.

New Zealand is also fortunate to have a reasonably strong biosecurity system, together with a relative abundance of water by world standards. Water supplies as well as soil health are critical parameters in producing healthy plants, both for food and for medicines.

New Zealand’s fruit and vegetables are widely known to have a great taste and high quality. This superior raw material quality has contributed significantly to our growing reputation as a country with some of the best cuisine in the world. The kiwifruit, hops, wine and berry industries have flourished and performed well for New Zealand in recent decades, all fundamentally due to their high quality characteristics. Thanks to a great deal of trial and error, hard work, investment of scientific knowhow and money, and most of all a whole lot of Mother Nature. These plant-based products are highly sought after in export markets, and as consumers we are privileged to have a wide selection of excellent quality foods and beverages available to us!

Medicinal plants (herbs) have also shown excellent quality parameters when grown in the New Zealand environment, and some examples of these follow.

Korean and American ginseng (Panax ginseng and Panax quinquefolium), seem to like it here, as very high levels of active ginsenosides have been achieved in ginseng roots. Thanks to work by the former Crop & Food Research (now Plant & Food Research) and a small number of dedicated growers (it takes many years and significant investment to establish and grow ginseng commercially), much has been learnt about ideal growing and harvesting methods, including how to grow it within Pinus radiata forests.

Leaves of ginkgo (Ginkgo biloba) are best known to help prevent dementia and other age-related disorders, as well as improve memory in healthy individuals. Levels of the active ginkgo flavone glycosides and terpenoids in New Zealand grown material are higher than those produced by trees grown in China, where most of the world’s ginkgo is sourced. This enables therapeutic levels to be achieved with a lower dose.

As with ginseng, golden seal (Hydrastis canadensis) is slow-growing and endangered in its natural habitat, yet global demand is high due to research validating its use as an antibacterial agent. This valuable medicinal plant was grown commercially by a couple of growers in New Zealand in the 1990’s, again with agronomy research support from Crop & Food Research. Much was learnt about how to grow it under local conditions, and laboratory tests showed the rhizomes contained very high levels of the active compounds hydrastine and berberine.

Many other medicinal herbs grown in New Zealand have been found by research studies or routine tests by manufacturing companies, to have very high levels of active phytochemicals. These include echinacea (alkylamide levels in the roots), arnica (another increasingly endangered species but New Zealand grown flowers containing high concentrations of sesquiterpene lactones), green tea (high epigallocatechin gallate and theanine levels), and valerian (high valerenic acid levels in the root and rhizome). The New Zealand blackcurrant industry has also grown rapidly over the past 20 years, catalysed by research showing significantly higher levels of antioxidant anthocyanidins in NZ berries than those grown in other countries, and anti-aging and cognitive-enhancing actions. Superior flavour profiles, and higher levels of vitamin C, have also been reported.

In summary, an appraisal of the performance of these “new” and more established medicinal plant crops in our New Zealand environment, shows that in all cases key quality parameters are significantly above average and in some cases are at the top of their field, when compared to the same species grown offshore.

New Zealand grown herbs are amongst the best in the world. Best for the health of ourselves, our pets and animals, our economy, our soils and waterways.

Kaitiakitanga in Māori, is about ensuring an intergenerational stewardship of the land, sea and waterways. Encouraging the growing of more both native and non-native medicinal plants in our own country rather than relying on cheap-labour countries to supply the bulk of our increasing needs, makes good sense.


Phil Rasmussen


With aging populations, the costs of drugs and institutionalised healthcare continually rising, and government drug funding agencies such as Pharmac always under the pump, it’s time to take a look at just what our taxpayer dollars are funding, and whether the current paradigm is working.

Total expenditure by New Zealand District Health Boards (Pharmac) on Drugs to the year ending 30 June 2018, was $870 million(1).

Health economists and policy advisers know it is unrealistic and unsustainable for governments to continue spending more and more of the GDP on the healthcare budget, and that shifting some of the growing burden of responsibility onto the population to take better care of their own health and wellness (‘self-care’), is a good strategy. However, the increasingly wide gap between those who can and can not afford the best available modern healthcare treatments and interventions, is very worrying. A ‘two tier’ health service in which the quality of state-funded services declines, as more and more pressure mounts on it, is inherently and morally wrong.

Primary care health services are not just those provided by General Practitioners, but also include a wide array of other inputs such as those by Pharmacists, Nurse Practitioners, Social Workers, Occupational Therapists and Drug Counsellors. These are aimed at disease prevention, health education and screening, and avoiding the need for hospital based care. A strong primary health care system is critical to improve the health of all New Zealanders, and reduce health inequalities between different groups(2).

However, the current primary health care system is neither keeping pace with nor adequately addressing the health needs of our population. Increasing challenges and treatment deficits are emerging particularly in areas such as mental health, substance dependency, diabetes prevention, disability services, dementia and infectious disease management. Too many New Zealanders are falling through the gaps or requiring repeated treatments, for recurring health problems(3,4), and health care staff stress levels and recruitment challenges, are worsening.

In New Zealand, most Medical herbalists and Naturopaths have undergone a 3 or 4 year course of study to the level of a degree. Apart from their high level of expertise in the use of specific plant-based medicines to help optimise health and overcome many illnesses, their training in nutrition and herb-drug interactions, and ability to take a ‘wholistic’, more integrative and preventive approach to an individual’s health, means they are well suited to advise and educate, on self-care and wellness interventions.

The estimated cost of a day’s hospital care in New Zealand during an influenza pandemic was put at $2,595 per patient in 2009(18), and current costs are probably in the range of $3,000 to $5,000, depending on the treatment required.  Compare this to the approximate $1,200 per year cost of a daily herbal tonic tailor-made to the patient’s needs and often focussed on prophylaxis. Even if it takes 3 years of such treatment to prevent a single night’s stay in hospital, it is a more cost-effective intervention, and with additional benefits.

Well-educated, higher socio-economic income bracketed and very sick people currently make up the bulk of patients seen by Medical Herbalists and Naturopaths in New Zealand. Meanwhile those on lower incomes who may benefit the most from its numerous inputs, are often unable to afford any non-subsidised treatment, and are effectively being excluded from having natural health as an option available to them.

Despite many holding the view that the benefits of natural health interventions are unproven, there is now compelling evidence from good quality scientific studies, supporting the use of specific herbal medicines when taken as adjuncts to drug medications being used for cancer, diabetes, heart failure, alcohol or drug dependency, and schizophrenia(5-16). There are several potential benefits of herbal medicine when appropriately prescribed to patients receiving conventional treatment for these and other conditions. They include improved patient outcomes, a reduction in the need for drug-based or other expensive medical care options, and thus a lower frequency of drug-related side effects and overall costs(17). Savings in the current drug budget alone, would enable an improved ability to fund new drugs or other healthcare interventions, including more emphasis on the most cost-effective approach, of disease prevention rather than treatment.

New Zealand’s commitment as a signatory to the World Health Organisation “Traditional Medicine Strategy, 2017-2023”(19), puts an obligation on the government to both further research into the area of traditional and plant-based medicines, and to progress statutory regulation of complementary medicine practitioners. There is an urgent need for more research into this area, and for political and funding support to enable the introduction of some such treatments in a regulated manner, into clinical practice.

However, in the case of Medical Herbalists, since 2005, successive New Zealand governments have rebuffed efforts to achieve statutory regulation as a profession under the Health Practitioners Competence Assurance (HPCA) Act. Despite a high level of professionalism shown by their national association, and comprehensive degree level courses being provided by training institutions, there seems little willingness on the part of the state to validate this profession, or ensure appropriate standards are in place to protect public safety, by progressing its latest application for statutory regulation lodged in 2016.

With the government’s so-called ‘Wellness Budget’ soon to be announced, it would be nice to know that more thought is being applied to preventing unwellness, and identifying ways to take some of the pressure off existing healthcare services. By finally recognising the untapped potential of well-trained and professionally registered Medical Herbalists and Naturopaths to make a greater contribution to future NZ healthcare options, we would at last see signs of a genuine commitment to the WHO Traditional Medicine Strategy, and a comprehensive health and wellness strategy for New Zealanders.



  1. Pharmac. Pharmaceutical Management Agency Annual Report for the year ended 30 June 2018, 2018.
  3. New Zealand Herald 17 Feb, 2016. Fears Canterbury mental health services may be slashed amid budget cutbacks.
  4. New Zealand Herald, 21 April 2019. Limited showers, no meal prep: ‘Ruthless’ plans to cut disabled care revealed.
  5. Rasmussen PL, Eur. J. Herbal Med. 3(1):11-21, 1997
  6. Rasmussen PL, Eur. J. Herbal Med. 3(2):13-19, 1997
  7. Pittler MH et al, Am J Med 2003; 114(8): 665-674.
  8. Doruk A et al. A placebo-controlled study of extract of ginkgo biloba added to clozapine in patients with treatment-resistant schizophrenia. Int Clin Psychopharmacol. 2008 Jul;23(4):223-7.
  9. Barton DL et al, Support Care Cancer 2010; 18(2):179-187.
  10. Barton DL et al, J Natl Cancer Inst 2013; 105(16):1230-1238.
  11. Biswal BM et al, Integr Cancer Ther 2013; 12(4):312-322.
  12. Chen EYH et al, Phytother Res 2012; 26:1166-1172.
  13. Zhang XY et al, J Clin Psychiatry 2001; 62(11):878-883
  14. Zhang XY et al, Psychopharmacology 2006; 188(1):12-17;
  15. Atmaca M et al, Psychiatry Clin Neurosci 2005; 59(6):652-6.
  16. Li J et al, Wuzhi Tablet (Schisandra sphenanthera Extract) is a Promising Tacrolimus-Sparing Agent for Renal Transplant Recipients Who are CYP3A5 Expressers: a Two-Phase Prospective Study. Drug Metab Dispos. 2017 Nov;45(11):1114-1119
  17. Rasmussen PL, Potentially beneficial herb-drug interactions. Practitioner Seminar, July 2016, Phytomed Medicinal Herbs Ltd, Auckland, New Zealand
  18. Wilson N et al, NZMJ 9 November 2012, Vol 125 No 1365; ISSN 1175 8716
  19. WHO Traditional Medicine Strategy: 2014-2023.