Manuka & More

I recently attended a very interesting Hui (Gathering) in Ruatoria and Te Araroa on New Zealand’s East Coast, entitled ‘Manuka and More’.  Around 15 researchers from Crown Research Institutes and industry representatives including myself gave talks on subjects related to the NZ native tree Manuka (Leptospermum scoparium), which grows prolifically around the coast, and provides nectar for honeybees which produce manuka honey.  Manuka honey is being increasingly recognised as a highly active natural product with benefits as an antimicrobial and wound healer, and global demand for it has soared in recent years. Similarly the volatile oil of manuka has antimicrobial and anti-inflammatory properties, and is increasingly sought after.

Studies into what makes manuka honey so special, and characterisation of its many different chemotypes and genotypes, has been a focus of much research in the past decade. To the East Coast locals, manuka was once regarded mainly as a scrub plant and nuisance that was cleared to make way for pastural farming of sheep and cattle, but with honey prices continuing to rise and there being little money now in wool, manuka is being allowed to re-establish itself in many areas. Additionally, a lot of effort is now going into planting nursery-raised seedlings bred from chemotypes thought to produce optimal quality and yields of honey and oil.

With the plantation model being in its relative infancy, research into the potential effects of planted manuka on the local pre-existing chemotypes, and whether the yield of honey or oil will in fact be as high as hoped from these cultivated plants, is an area for ongoing investigation.

A growing number of local East coast people and Maori-controlled enterprises are now getting into the honey producing business, and the number of hives in NZ has nearly doubled from around 350,000 to 700,000 over the past 5 years. The sustainability of this level of honey production is another area requiring research, particularly as bees only feed off manuka (and kanuka) nectar for around 6 weeks each season. Monitoring their activities and ensuring they have sufficient food for the remaining 46 weeks of the year, is important.

Of the various flowering plants NZ honey bees feed off, Willow trees (Salix species), are an important source of pollen and protein for bees to feed their brood in the spring time, thus helping them to expand their population and gain maximum strength before the start of the honey flow season. Around the East coast a large number of willows grow particularly along waterways and on erosion prone areas. While the biggest problems for young willows are grazing animals and pests such as possums, rabbits and hares, an emerging pest is also the giant willow aphid which first appeared in NZ in 2013. Apart from infesting willow trees, this can boost the populations of wasps that attack honey bees.

smaller-leptospermum-scoparium-flower-manuka-flower-julyWhile not pleasing to all, other flowering plants such as the invasive introduced gorse (Ulex europaeus), presently plays an important role as a food source for bees in some areas. However, we should be planting other native species such as Hoheria (Hoheria populnea),  Whauwhaupaku or Five Finger (Pseudopanax arboreus) and many others, to provide pollen and nectar as a replacement for that from this imported thorny plant.

Other research presented at the Hui related to the role that mycorrhizal fungi, which grow on the roots of most plants, may have in ensuring the health of the manuka shrub. Most plants co-exist with these fungi, which help them better absorb nutrients from the surrounding soil, and can also help with disease prevention. Also monitoring for potential disease or infestation threats to Manuka such as Myrtle rust, a serious fungal disease not present in New Zealand, but which can affect other plants in the myrtle (Myrtaceae) family.

Recent studies suggesting that manuka seems to be useful at soaking up excremental pollution, and thus may be an ideal tree to plant alongside waterways polluted by effluent runoff from our overly intensive dairy industry, point to yet another exciting development in our understanding about this amazing native plant.

Overall, the range and quality of the diverse areas of research being undertaken, was most encouraging. This combined with the hands-on experience and traditional knowledge of the local Ngati Porou people who are increasingly finding meaningful employment opportunities from manuka-based businesses, gives great encouragement to the future social, economic and environmental wellbeing, of this beautiful area of New Zealand.

Manuka Oil as an Alternative to Antibiotic Creams

New Zealand has a higher incidence of Staphylococcus aureus infections than anywhere else in the developed world, and there has been a significant increase in the number of infections over the past decade, with Māori and Pacific children particularly affected.


Over usage of an antibiotic is likely to have contributed to this paradoxical increase in serious skin infections, according to results from a Health Research Council funded study. This revealed an increase in the prevalence of resistance in Staphylococcus aureus from 17% in 1999, to 28% in 2013. Dr Deborah Williamson, the clinical microbiologist who lead the study, made the statement in a recent press release that “The increase that we’ve seen in the incidence of serious skin infections in New Zealand children has happened at the same time as an increase in the dispensing of topical fusidic acid to treat skin infections”(1).

Fusidic acid is an antibiotic derived from the fungus Fusidium coccineum and was first released for clinical use in the 1960’s. A 2% fusidic acid cream is currently recommended as a first-line treatment for serious skin infections such as impetigo (school sores), infection of the hair follicles and boils. Most of these are due to the bacteria Staphylococcus aureus, including the notorious methicillin resistant Staphylococcus aureus (MRSA). Like all antibiotics, drug resistance can develop, and this is invariably at a rate proportionate to the extent of usage.

In a paper published in the New Zealand Medical Journal last December, Dr Williamson reviewed the history and usage of topical antimicrobials in New Zealand (2).

This painted a somewhat alarming picture, and the fusidic acid story is an all too familiar one. Another topical antimicrobial agent widely used throughout the 1990s, mupirocin (Bactroban©), was for many years made available to purchase ‘over-the-counter’ (OTC). This led to high levels of use, and subsequent high rates of resistance, and by 2000, approximately 14% of S. aureus isolates displayed high-level resistance to mupirocin(3) . From April, 2000, regulatory changes lead to mupirocin being restricted again to ‘prescription only’, and the resulting decreased usage lead to a fall in the prevalence of high-level mupirocin resistance in S. aureus from 14.2% in 2000, to 8.3% in 2014 (4).

New Zealand is not alone in having a high rate of bacterial resistance to topical antimicrobials, and resistance to antibiotics poses a major global threat, according to a 2014 report by the World Health Organisation(5). Resistance is happening in every region of the world, and unless some major developments take place soon, humankind could be heading towards a time when once again, antibiotics cannot be relied upon to protect against simple infections including those that are risk factors associated with surgery. Development of strategies to mitigate further increases in antimicrobial resistance to topical treatments, is urgently required(6, 7).

Key to this, should be effective wound management. This should combine mechanical-chemical procedures such as debridement, antiseptics, and antimicrobial supportive compresses to help remove the biofilm (an association of microbes and slime which adheres to the surface of the wound, delaying granulation tissue formation and migration of epithelial cells).

Limitation of the level of usage of drug-based antimicrobials, or using two or more of them together rather than alone, and avoidance of topical antibiotic use in common conditions such as acne, are other ways to help reduce the likelihood of resistance(8).

Plants contain a large number of diverse chemicals (phytochemicals) which they produce as defence tools to enable them to survive in their particular environment, and some of these have potent antibacterial activities which can help us fight a wide range of common skin infections.

manuka-2The New Zealand native Manuka (Leptospermum scoparium) is one of these, and the ability of certain forms of Manuka Honey to act as potent healing agents for wounds and ulcers, is becoming increasingly recognised(8). Many clinical trials have now shown manuka honey dressings to have unique healing properties in chronic leg ulcers and other stubborn skin infections, and synergistic antimicrobial activities with various antibiotics, have recently been reported(10,11).

Manuka’s medicinal properties extend way beyond those of the honey that bees manufacture from its pollen, however, and other parts and extracts of this wonderful plant, have therapeutic activities. Manuka essential oil has also been shown to exhibit powerful antimicrobial properties, particularly against Staphylococcus aureus and other Gram positive bacteria, yeasts such as Candida albicans and fungi such as Trichophyton rubrum, responsible for athletes foot. Manuka oils which are rich in beta triketone compounds, appear to have the strongest antimicrobial activity.

The extent to which topical application of an extract of this plant can rival drug-based treatments at overcoming sores, was highlighted by a research project by two students at Whangaroa College in Northland recently. After hearing about a fellow student’s spider bite that wouldn’t heal until it was treated with a native plant preparation, the two students, Cheyenne Rush and Georgia Mills, decided to investigate the antibacterial properties of manuka essential oil and an extract of another native plant kawakawa (Macropiper excelsum).

Their experiment, which they entitled Te Rongoa Māori , involved collecting and growing colonies of bacteria, spreading these onto agar plates and applying a quarter of a teaspoon of each product to be tested. The relative rates of decline of the bacteria was recorded daily for 14 days, for the manuka oil and kawakawa extract preparations, in addition to the well known antiseptics Savlon® and Betadine®, which were applied to other agar plates as controls.

The results showed that manuka oil was the most powerful antibacterial, followed by Savlon® then Betadine®, with the Kawakawa leaf extract the least effective. Cheyenne and Georgia’s project thus showed that a simple, traditional plant preparation can be more effective than prominent antiseptic products in fighting wound colonising bacteria. It also won them a top prize at the recent Top Energy Far North Science and Technology Fair, which involved more than 150 participants from 10 schools in upper Northland(12).


  1. Media Release from the Health Research Council, Soaring rate of skin infections linked to resistance.NZ Doctor, 20 September 2016.
  2. Williamson D et al, A bug in the ointment: topical antimicrobial usage and resistance in New Zealand. NZ Med J 2015; 128(1426):103-9.
  3. Upton A et al, Mupirocin and Staphylococcus aureus: a recent paradign of emerging antibiotic resistance. J Antimicrob Chemother. 2003; 51:613-617.
  4. Heffernan H et al, Demographics, antimicrobial susceptibility and molecular epidemiology of Staphyloccosu aureus in New Zealand, 2014.
  5. Antimicrobial Resistance: Global report on surveillance. World Health Organisation, 978 92 4 156474 8; (
  6. Williamson D et al, Missing in action: an antimicrobial resistance strategy for New Zealand. NZ Med J, 2015; 128(1427):65-67.
  7. Williamson DA, Hefferman H. The changing landscape of antimicrobial resistance in New Zealand. NZ Med J 2014; 127(1403):41-54.
  8. Walsh TR, The Lancet Infectious Diseases, 2016; 16(3): 23-33
  9. Carter DA, Front Microbiol 2016; 7:569
  10. Muller P et al, PLoS One 2013; 8(2):e57679
  11. Liu M et al, Front Microbiol 2015; 5:779.

Respiratory Health in Singapore and Herbal Options

I recently spent a couple of days in Singapore, where herbal product needs are currently somewhat different to those in my New Zealand home. September in Singapore generally marks the start of the 3-4 month so-called ‘Haze season’, a period in which the air can be tainted for days on end, with a haziness due to smoke drift from fires in nearby Indonesia. The annual haze season started early this year, in late August, and on 26 August Singapore’s 24 hour Pollutant Standards Index (PSI) entered the ‘unhealthy’ range of above 100, while its 3-hour PSI reached 215(1). As with the haze last year, when the PSI reading at times exceeded 300, most people didn’t venture out without a face mask.

Agricultural fires are an annual occurrence across Sumatra and in parts of Kalimantan on Borneo, as corporations as well as small-scale farmers use slash-and-burn methods to clear vegetation for palm oil, pulp and paper plantations. As well as trees and forests, there is much peat land in these parts of Indonesia, and peat fires can burn and smoulder underground for several months.

Tsmog-over-the-city-1197986-639x359he haze contains particulate matter, fine particulate matter, heavy metals and poly aromatic hydrocarbons, and at its peak can measure hundreds of kilometres across. As well as affecting Singapore’s air quality and visibility, the air pollution can spread to Malaysia, southern Thailand and the Philippines. This can have a major impact on the health of the people and plants of these countries, and of course those of Indonesia itself.

Fine particulate matter especially, can enter deep into the lungs, causing respiratory illnesses and lung damage. Particulate matter pollution and its constituents also damages plant morphological structure, flowering, water content, growth and reproduction, and can have genotoxic impacts(2). Epidemiological studies have shown an increase in morbidity and mortality rates from chronic obstructive pulmonary disease after exposure to elevated levels of air pollution, and associations between lung cancer and cardiovascular diseases, are well established.

This situation leads to increased demand for herbal lung health products in Singapore by the local population seeking to do more than wear a mask to protect their lungs against the damaging effects of the haze. Herbs that gently support and encourage the natural expectoration process of the millions of cilia cells lining our bronchial trees, whose role is to remove excess mucus and potentially harmful substances such as particulate matter or unwanted allergens, are therefore useful. These include mucilaginous (polysaccharide hydrocolloid rich) and expectorant herbs such as Marshmallow (Althaea officinalis), Mullein (Verbascum Thapsus) and the NZ native Hoheria (Hoheria populnea). Other traditional lung herbs such as Elecampane (Inula helenium), White horehound (Marrubium vulgare) and Hyssop (Hyssopus officinalis), are also useful. For Singaporeans having to live in the seasonal haze, or citizens of cities in China and many other countries where air pollution is a regular feature of life, in order to help protect against reduced levels of cellular oxygenation and an increased risk of bronchial congestion, asthma, lung cancer and heart disease, these herbs can be useful daily tonics.

In addition, certain herbs have chemo-preventive or protective effects against cellular damage and carcinogenicity, that may be helpful when exposure to air pollution is unavoidable. Apart from its anti-inflammatory, antimicrobial and antioxidant properties, evidence suggests a possible protective effects against lung cancer by roots of the warming volatile oil rich Elecampane(3).  The root of the fiery Horseradish (Armoracia rusticana)(4), and aerial parts of Nasturtium (Tropaelum majus),(5-6) also both contain phytochemicals with established chemo-preventive effects against cancers, that seem to be well absorbed into the bloodstream when taken orally. These and expectorant actions make them specifically indicated to help prevent lung damage in those exposed to regular dangerous levels of airborne pollution, such as the annual Haze in Singapore.

untitled-design-17While considering this situation, I couldn’t help notice the presence of palm oil still in chocolate sold throughout Singapore, unlike certain other countries where it has been removed due to public concerns around the environmental impacts of a huge increase in palm oil plantations. Similarly the importation of palm kernels for use as a supplementary feed to dairy cows in New Zealand, needs a mention. Reflecting on this as well as the widespread use of palm oil in cheap vegetable oils and in many other food and non food consumer items found globally, there is clearly a need to address the underlying cause of such environmental pollution and factors responsible for poor human health, in a more integrative way. This burning of indigenous forests in Indonesia is related also to poverty as well as poor regulation by authorities there, but corporate greed, consumer usage and lack of awareness or concern for environmental and economic impacts, is contributory.

Until the slash and burn method of land clearing in Indonesia is stopped, health effects on the millions of people living in the region, and ongoing widespread loss of bio-diverse rich forests and destruction of the habitat of endangered species such as orangutans, tigers, elephants and rhinos, will continue.



  1. “The haze is back across South East Asia”. BBC. Retrieved 26 August 2016.
  2. Rai PK, Ecotoxicol Environ Saf 2016; 129:120-136.
  3. Li Y et al, Z Naturforsch C 2012; 67(7-8):375-380.
  4. Weil MJ et al, J Agric Food Chem 2005; 53(5):1440-1444.
  5. Platz S et al, Anal Bioanal Chem 2013; 405(23):7427-7436.
  6. Pintao AM, Planta Med 1995; 61(3):233-236.

Withania Improves Sexual Satisfaction in Women

Human sexual responses and functions are highly complex, with sexual desire and activities being influenced by multiple psychological, physical, environmental and relationship factors.

‘Sexual dysfunction’ is defined as difficulties that occur during the sexual response cycle that prevent the individual from experiencing satisfaction from sexual activity. While sexual dysfunction in men is relatively easy to characterise, female sexual responses tend to be more complicated, making measurement of appropriate contributory and outcome factors and the definition and treatment of female sexual dysfunction (FSD) more difficult (1).

Development of drugs such as sildenafil and others has made a big difference to the sex lives of men with erectile dysfunction over the past 15 years, but until now few drug treatment options exist for the most common sexual complaint in women, decreased sexual desire.

IMG_2611.CR2Ashwagandha (Withania somnifera) is a herb native to India and the Asian subcontinent, used as a tonic and treatment for a wide range of health conditions and perceived benefits. Known among herbalists as an ‘adaptogen’, its best known action is to help improve the body’s resilience to stress. Withania normalises blood levels of cortisol and other adrenal hormones during chronic stress, and exhibits a large number of actions suggesting an ability to insulate against adverse environmental stressors. This results in reduced anxiety, and a subtle but welcome retention of a sense of still being ‘in control’, during times of stress (2,3).

Withania is also used traditionally to treat men with erectile dysfunction and performance anxiety, and clinical studies have found improvement in sperm concentration and motility(4-6).  This reputation extends also to helping address diminished sexual desire in women, particularly where a depleted nervous system is contributory. A clinical study recently conducted in India, provides compelling data suggesting that it may well assist some women to achieve enhanced sexual satisfaction(8).

The study involved 50 women aged 21–50, all of who were in steady heterosexual relationships, and previously or presently engaged in sexual function for several years. Most were married women from affluent households who were not employed, but reported as having stressful lives due to social demands, child rearing, and husbands’ high expectations.

The women were divided into two groups, and both went through a counselling program consisting of two seminar presentations and an individualized consulting session on addressing FSD. One group also consumed capsules containing a 300mg extract of Withania (standardised to contain not less than 5% withanolides), and the other group placebo capsules, twice daily for 8 weeks.

The primary outcome measure was the Female Sexual Function Index (FSFI), a self-report 19-item questionnaire which was used at the beginning of the study, then at 4 and 8 weeks later(7). This included domain scores for desire, arousal, lubrication, orgasm, satisfaction, and pain. The FSFI Total Score was a weighted sum of these, and as expected was low at the study’s commencement.

Withania treatment lead to a significantly higher improvement than placebo in the FSFI, at both 4 and 8 weeks after starting the study. This increased from 13.63 to 23.86 in the treatment group, but only from 13.57 to 20.06 in the placebo group, a statistically significant difference. While mean scores for sexual desire or the number of total sexual encounters were similar in both Withania and placebo groups, mean scores for lubrication and orgasm were higher in Withania treated rather than placebo treated women. Women in the Withania treated group also reported a marked improvement in sexual satisfaction scores at 8 weeks, these increasing 1.4 points (from 2.35 to 3.79), versus only 0.36 points (from 2.34 to only 2.7) in the group of women who received counselling only (8).

Results from this study don’t suggest that Withania is an aphrodisiac, as Withania supplementation failed to statistically improve sexual desire or the number of total sexual encounters. However, the fact that Withania caused a marked increase in overall sexual satisfaction, in what was a relatively small clinical trial, offers considerable promise for women seeking a natural and safe herbal option for what is increasingly being recognised as a relatively common complaint in our modern world.



  1. Chen CH et al, Taiwan J Obstet Gynecol 2013; 52(1):3-7.
  2. Cooley K et al, PLoS One 2009 Aug 31; 4(8):e6628.
  3. Rasmussen PL, Phytonews 39, Nov 2013; ISSN 1175-0251, published by Phytomed Medicinal Herbs Ltd, Auckland, New Zealand.
  4. Rasmussen PL, Phytonews 36, July 2011; ISSN 1175-0251, published by Phytomed Medicinal Herbs Ltd, Auckland, New Zealand.
  5. Pesch S et al, Theriogenology 2006; 66(2):307-313.
  6. Shukla KK et al, Fertil Steril 2009; 92(6):1934-1940.
  7. Rosen R et al, Journal of Sex & Marital Therapy, 2000; 26(2):191-208.
  8. Dongre S et al, Biomed Res Int 2015; 2015

Herbal Medicines: Organic or Not?

Part 2

The world’s appetite for organics is growing at an annual rate of approximately 25%. In 2014 the global market for organic food was estimated at US$80 billion, the largest markets being the USA (US$35.9 billion), Germany (US$10.5 billion) and France (US$6.8 billion). Demand for organic food in China is also increasing, with estimated organic retail sales worth US$4 billion in 2014 (1).

Unfortunately though, we also live in an age of Greenwashing, which is the marketing or promotion of products as being more sustainable and organic than what they in fact are. Words such as ‘organic’ or ‘natural’ have market appeal, and their meanings are frequently massaged and misused simply to promote sales. Many companies and large corporates are falling over themselves to be seen as offering healthier products, without a genuine change in approach or concern applied to the direct and indirect harm caused by agrichemicals and non-sustainable farming methods. Such greenwashing has become common, including in New Zealand which is currently an unregulated organics market. It is important that relevant parameters are checked, audited and certified by a trusted organic certification agency, and consumers are right to ask for proof of authenticity.

In parallel with the above trends, we’ve seen a rise of a vocal minority who take relish in challenging and continuing to try and dispel, the growing consumer awarenesss of organics.  There is no shortage of such sceptics in countries such as New Zealand or the U.S, who dispute the benefits of organic food production over conventional farming.  In countries such as Germany and Denmark on the other hand, the importance of organic agriculture for personal health, childrens’ health, farmworkers and for the future of our planet, has much more widespread acceptance.

Hyssop.jpgScience is also starting to suggest superior nutritional properties for organic crops. A ten year comparison of the influence of organic and conventional crop management practices on tomato flavonoid content, measured higher levels of the antioxidant lavonoids quercetin and kaempferol in organic tomatoes(2).   Studies have also found enhanced organoleptic and taste qualities of organic versus non organic apples(3).

New Zealand organic production and exports have grown in recent years, but from a low base, and at a rate slower than that seen in many other countries. This is for many reasons, but probably partly attributable to the fact that unlike in Europe, no subsidies for organic conversion are provided during the 3 year conversion period. This means that when land dependent on chemical inputs applied over many years is cold-turkeyed off these, resulting in substantial productivity drops particularly in the 1st year, the farmer has to stomach substantial short term financial losses, which can be a significant disincentive.

Once certified, however, substantial benefits can manifest. New Zealand farmers producing organic milk for example, are projected to be paid $9.20 a kg of milksolids for 2016/2017, more than twice that of the $3.90 a kg currently paid to their conventional farming colleagues. While global milk prices have been volatile in recent years, prices for organic dairy ingredients have remained at relatively high levels, because consumers’ appetite for organic milk products is growing faster than supply(4).

The popularity of herbal products for ‘detoxification’ or ‘liver cleansing’, and those treating childrens’ ailments, is increasing. However, as with non-organic fruit and vegetables and dairy products, the large farm production and commodity based trading systems for most medicinal herbs can also involve significant levels of agrichemical inputs. Thus unless documented proof of their organic status is available, or the manufacturer is routinely testing every batch for pesticides and heavy metals, there can be no guarantee that residues of compounds which may impact negatively on human health, are not present in herbal medicines.

It is time for non-organic production methods to be avoided by growers and consumers who care about their health and that of the planet and future generations. This should apply to all facets of agriculture, including medicinal plant production.


  1. Hoare B, Organics Aotearoa New Zealand, 2016 New Zealand Organic Sector Report.
  2. Mitchell AE et al, J Agric Food Chem 2007; 55(15):6154-6159.
  4. Paul Grave, head of Fonterra cooperative affairs, Waikato, in Organic dairy farms reap rich rewards. NZ Herald, 7 May 2016

Herbal Medicines: Organic Or Not?

I’ve heard much discussion lately about how important Organic certification is for herbal medicines, and feel it’s appropriate to contribute my 2 cents worth.

The Oxford Dictionary defines ‘Organic’ in relation to food or farming as being ”produced or involving production without the use of chemical fertilisers, pesticides, or other artificial chemicals”.  Most organic certification agencies today extend this definition to exclude products made involving genetic modification (GMO’s).

Echinacea bumble bee

Humans have applied natural compounds and simple chemicals such as copper sulphate and lime as pest control methods in agriculture for a long time, but the use of synthetic pesticides accelerated in the 1940’s with the development of organochlorines such as DDT, aldrin, dieldrin, chlordane, parathion, and 2,4-5-T. Usage of agrichemicals to improve productivity and profits has been the norm for most types of farming ever since. Today a whole host of different synthetic chemicals are used in modern horticulture, ranging from fertilisers to herbicides to fungicides to insecticides to plant growth regulators.

Widespread and global contamination of the environment with organochlorines has occurred, and pesticide residues are now detectable in virtually all wildlife, well water, food and in humans. The long term effects of such compounds on the environment as well as human and plant health are unknown, as are those of residues of chemicals such as antibiotics and bovine growth hormones found in consumer products such as meat or milk. What is known, is that pesticides can have significant chronic health effects, including but not limited to cancer, neurological effects, diabetes, respiratory diseases, fetal diseases, hormone disruption and genetic disorders.

biogro standard 2009Most medicinal herbs are grown in developing countries, where programmes to control exposures to agrichemicals are either limited or non-existent. Many agrichemicals are toxic to handle, and pose significant risks, particularly in the event of accidental spills or inhalations. Children are particularly vulnerable to their harmful effects, with even very low levels of exposure during development potentially having adverse health effects. The World Health Organisation estimates that there are 3 million cases of pesticide poisoning each year and up to 220,000 deaths, primarily in developing countries.

Apart from the direct impact on humans, insects or animals who consume plant extracts either as foods or medicines which contain synthetic and potentially harmful chemicals, the effects that usage of chemical agents in agriculture have on the health of the planet’s bees, soils, waterways, and air, are of great concern.

The impact of farming practices on soil health is poorly understood, although soil samples from conventional farming generally contain higher levels of organochlorine pesticide residues compared to organic farming(1). The importance to soil health of diversity within the bacterial and fungal communities living within the soil, is becoming increasingly recognised, and this is greater under fully organic crop management(2,3).

The link between neonicotinoid pesticides and Colony Collapse Disorder in bees has been acknowledged by regulators in many countries, but took many years to happen. Also they remain in widespread use in some countries, despite potentially posing a serious threat to the world’s bee population upon which much of agriculture is dependent.

Given these adverse effects, and the absence of long term data in support of many new compounds being 100% safe, it is little wonder that consumer appetite for the use of synthetic and chemical-based pesticides continues to wane. While to date this trend towards organics seems to mainly apply to foods, given that most users of herbal medicines are taking them to optimise their health including to help counteract the effects of harmful environmental exposures, it would seem highly appropriate for there to be a preference for certified organic rather than non-organic herbal remedies.



  1. Witczak A, Abdel-Gawad H. J Environ Sci Health B. 2012; 47(4):343-354.
  2. Reilly K et al, J Sci Food Agric 2013; 93(15):3700-9.
  3. Verbruggen E, Toby Kiers E. Evol Appl 2010; 3(5-6):547-560.

Quality in Herbal Medicines

Herbal medicine usage throughout the world, continues to increase. This growth is due to increased concerns about drug safety, favourable clinical trial results on herbal products, the rising cost of mainstream medicines, and more awareness of preventive and wellness enhancing measures.

It is a fundamental expectation of all consumer products, that the purchaser or user has a right to feel confident that the product contents as stated on its packaging and in marketing claims, are indeed true and accurate.  For medicines especially, this is absolutely imperative, as the stakes can be very high when taking a medicine for a chronic or serious health condition, and taking something different to that which was intended when unwell, can have serious consequences. It is therefore essential, that herbal medicine manufacturers have appropriate systems and procedures in place, to ensure adequate quality assurance can be guaranteed for their products.

When shopping for fresh vegetables and fruit it is relatively easy to assess their likely quality parameters through appraising visible attributes and knowing their source. Knowing that a herbal material was of good quality when it was processed by a herbal medicine manufacturer into a capsule, tablet or liquid preparation, and that such processing incorporated satisfactory standards, is however, very reliant on the manufacturer.

While the majority of herbal products are generally considered safe due to their age-old usage, side effects can occasionally occur. Most of these are mild and due to unpredictable allergic reactions. However, an alarming proportion of adverse effects occur due to insufficient quality of the herbal product itself, including accidental contamination or even intentional adulteration with drugs(1). This is inacceptable in a 2016 or future healthcare environment.

Many instances exist where natural health products have been shown to have contents that are very different to what is stated on their label(2-5). Natural health is a large global business and as with all industries it attracts a small percentage of unscrupulous traders who take advantage of the deficits and sometimes absence of appropriate regulations, to increase their bottom line at any cost.

Biological contaminants (microbes and other organisms) and chemical contaminants (mycotoxins, toxic elements such as heavy metals, and pesticide residues) are the most common contaminants of medicinal herbs and herbal products. Apart from the safety implications, species misidentification and accidental contamination with other plant material or microbes, can often be reasons for lack of effectiveness.QA liquid sampling

In recent years we have seen many instances of low quality Ginkgo biloba extracts being intentionally adulterated with flavonoid compounds from cheaper plants(6). Use of cheaper Chinese and other species of Actaea instead of the true Actaea racemosa species in Black Cohosh products(7), or adulteration or substitution of commercial Berberis aristata and its herbal products with inferior-quality substituents(8), is unacceptably high.

A 2015 analysis of 150 dietary supplements marketed in the U.S. to increase sexual performance, found that 61% of these were adulterated with the drugs sildenafil, tadalafil and vardenafil, and 34% with their structurally modified analogues. Only 31% of the samples could be considered as true herbal/natural products(9). It is perhaps relevant that the U.S. has a relatively lightweight regulatory system in place for so-called ‘Dietary Supplements’, and unlike Australia, Canada and Europe, there is no requirement for ingredients of products sold direct to consumers to first be independently assessed for safety, before being approved for use(10).
Consumers and patients should demand 100% surety that they are taking what is stated and intended, but this will only be achieved with appropriate standards and regulations in
place. To meet these needs, most countries around the world now require natural health product manufacturers to comply with the requirements of what is known as the code of Good Manufacturing Practice, or GMP. GMP is a comprehensive system under which manufacturers should undertake independent tests such as validation of the authenticity and  absence of contaminants for raw materials, tests for pesticide contamination in herbs that have not been grown in certified organic conditions, and microbial and other quality assurance testing on all products prior to them being released for sale. These are reasonable minimum standards that all consumers and patients purchasing and ingesting a herbal medicine or natural health product for their health or medical condition(s), should expect.

New Zealand, however, is now the only developed country in the world not to require GMP certification for natural health product manufacturers, and legislation to introduce some basic standards for the industry, is hugely overdue. While many local companies are voluntarily GMP certified, others claim to have comprehensive manufacturing standards in place, yet most of their products are made using imported raw materials where the supplier’s specification is too frequently accepted at face value, with little in the way of independent checks or tests. This has the potential to cause serious human harm, and damage the local industries reputation and potential in growing offshore markets.

To help prevent potentially harmful effects on consumers taking herbal and other natural health products, and ensure the enormous export potential of the local New Zealand industry is realised, it is imperative that the manufacturing and quality standards included in the forthcoming Natural Health Products Bill, are robust and internationally recognised. New Zealand continues to build a world class reputation for its food and beverage industry sectors, but only upon a backbone of a comprehensive and appropriate regulatory framework. We can do the same for the natural health products industry, but not unless the government is prepared to step up to this now urgent task.


  1. Vaclavik L et al, Anal Bioanal Chem 2014; 406(27):6767-90.
  2. Bateman J et al, Pharmacoepidemiol Drug Saf 2011; 20(10):1104-9
  3. Toomey VM et al, J Pharm Biomed Anal 2010; 59:50-57.
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How Quickly should Herbs Work?

One of the most common questions I have from my new patients when recommending or prescribing them herbal medicines for the first time, is ‘how long will it take to work’? This is totally understandable, particularly when they are often grappling with a serious health complaint, or have pushed their budget to afford to pay for an unsubsidised consultation and herbal treatment.


When my answer is invariably that that they should notice an improvement either straight away or within a short space of time, the reaction is usually one of surprise. This is because there seems to be a fairly common misconception among consumers and many health practitioners that herbal medicine and the ‘natural approach’ to treating a health ailment usually takes a long time to manifest results.

There is no question that certain drugs such as the steroid prednisone, can invoke a dramatic and sudden amelioration in inflammation or related symptoms, or that use of nitrolingual spray has a virtually instantaneous effect in angina.  However, for most everyday human health conditions, herbs work as quickly as drugs in resolving the problems concerned.

Diarrhoea and dysentery, are situations where a rapid rather than protracted response is called upon when taking a remedial treatment. Until a couple of hundred years ago when refrigeration was invented and human public health measures improved, such lurgies were also extremely common. Back then and still today in many countries, most communities relied heavily on the use of local tannin-rich herbs with astringent properties, to help manage such problems. These ranged from Agrimony (Agrimonia eupatoria) and Oak bark (Quercus robur) in European herbal medicine, to Koromiko (Hebe salicifolia) and Tanekaha (Phyllocladus trichomanoides), in traditional Mâori medicine. Tannin-rich plants were also applied as poultices and other topical preparations to help stop bleeding from battle wounds or accidents, where again rapid haemostatic actions which halted such bleeding and promoted healing as quickly as possible, were very important. Such use included well known plants such as Tormentil (Potentilla tormentilla), Harakeke (Phormium tenax) and Pohutakawa (Metrosideros excelsa). It is also reflected in the Latin names of other well-known plants such as Yarrow (Achillea millefolium), used by the Greek warrior Achilles on his soldiers spear and sword wounds.

One of the best treatments for bruises, strains and sprains, Comfrey (Symphytum officinale), starts providing pain relief and an anti-inflammatory effect within 30 minutes of application, according to clinical trials on an ointment preparation. This is just as rapid as mainstream gel treatments containing non-steroidal anti-inflammatory drugs (NSAID’s).

Despite drug companies throwing billions of dollars at research aiming to develop a superior analgesic, the Opium poppy derived alkaloid morphine remains the most highly regarded and used analgesic for major pain. This status has been maintained not only because of its ability to overcome intense pain, but also the speed of its onset of action. Similarly, the rapidity of onset of mood changes following marijuana smoking, is another testament to how quickly herbs can produce their many pharmacological effects.

Insomnia can be a highly debilitating condition which requires effective and fast acting remedies. The use and reputation of well-known herbs such as Valerian, Kava, Passionflower and Skullcap as aids to sleep, is based upon acute or single dose ingestion shortly before retiring, in the same manner as sleeping tablets such as zopiclone. Their effectiveness varies from person to person, and is of course dependent on adequate doses of sufficiently good quality product, but they should either work straight away, or there’s little point in persisting. Use of these and other herbs as part of an approach to managing anxiety disorders, should also invoke some degree of relaxation within an hour or so of ingestion, in a similar manner to benzodiazepine drugs such as diazepam (Valium®). Both drugs and herbs seem to work on the same sites of action (GABA, gamma-aminobutyric acid receptors) within the body, to produce these anxiolytic actions.


However, just as with drugs, not all herbs produce resolution of symptoms straight away, and the improvement in feelings of depression following appropriate treatment, is an example of where a longer timeframe is involved. Like antidepressant drugs, the herb St Johns Wort (Hypericum perforatum),  only manifests its antidepressant action after 3-5 weeks of daily administration in most cases. This is probably related to the time required for its active phytochemicals to modulate serotonin and other involved neurotransmitter systems, in order to produce an antidepressant response.

To summarise, we are often mislead into thinking that ‘herbs take longer to work than drugs’. While the timeframe between starting herbal treatment and a response being achieved is highly variable depending on the condition and person being treated, effective herbal medicine treatment should in most cases take no longer than that of drug treatments.