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Curr Nutr RepDOI 10.1007/s13668-013-0057-z The Marketing of Dietary Supplements:A Canadian Perspective # Springer Science+Business Media New York 2013 Abstract Dietary supplements are widely used in Canada.
from plants and animals. As they are bioactive substances, This paper presents an overview of commonly-used supple- they therefore pose a risk of adverse side effects. Three- ments, including their purported health benefits, as well as the quarters of Canadians take supplements, and one in three uses best current evidence as to the accuracy of these claims. Types of supplements discussed include herbal products, glucos- Hundreds of different supplements are sold in Canada.
amine, chondroitin, weight-loss products, and exotic fruit Claims are routinely made that these supplements deliver juices. The paper also discusses possible harmful side effects various benefits, but in the large majority of cases, the from various supplements, especially herbal products. It then supporting evidence is weak or even non-existent. Only in a examines the major methods by which supplements are small number of cases is there strong supporting evidence of marketed, including health food stores (HFS), pharmacies, the benefit of supplements. We see this most clearly with and supermarkets; newspaper, magazine, and TV advertising; micronutrients. Multivitamins – meaning pills containing a and multilevel marketing. Most of the marketing of supple- broad spectrum of vitamins and minerals – may be recom- ments is concentrated on products that are expensive but mended for various groups of people, such as the elderly, where supporting evidence is quite weak, and misleading whose diets are low in nutritional quality. Iron and folic acid and dishonest marketing strategies and claims are widespread supplements may be of value for many women during their problems. Dietary supplements are regulated in Canada by the reproductive years. There is strong evidence that most people Natural Health Products Directorate, an agency of the federal in Canada have inadequate vitamin D status. Supplements government. The new regulations came into force in 2004, but may improve bone health and enhance resistance to cancer – misleading and dishonest marketing is still widespread.
especially colon cancer – and other diseases []. The casefor vitamin D supplementation is strongest among the elderly, Keywords Supplements . Health food stores . Herbs .
people with dark skin, and those who expose little skin to the Multilevel marketing . Marketing methods . Advertising sun. Canada’s Food Guide now recommends that all peopleover age 50 take a supplement of 400 IU (10 μg) of vitamin Dper day. There is evidence that many people need a signifi- cantly higher dose, at least 1000 IU (25 μg) per day although this area is controversial.
Dietary supplements refer to any substance taken in addition Most of the marketing of supplements is concentrated on to regular food. Supplements include vitamins, minerals, ami- products where the supporting evidence is far weaker but the no acids, herbs, enzymes, and various substances extracted profit potential is far greater. Here, we examine a selection ofexamples. The paper then surveys the main methods of market-ing supplements in Canada and documents the widespread prob- Hope springs eternal in the human breast.
lem of misleading and dishonest marketing strategies and claims.
Regulating the supplement industry and protecting con- sumers from fraudulent and misleading claims presents many Centre for Science, Athabasca University, Athabasca, Alberta T9S challenges. The paper reviews the current regulatory status of confounding. The most reliable results came from a RCT carried out across the USA on 3,070 people aged 72 to 96who were given either the herb or placebo and were then monitored for six years. Findings from this large RCT re-vealed no benefit in either memory function or rate of cogni- Each of the following herbal supplement assessments is based primarily on information from two reliable Internet sites – the Taken as a whole, these findings provide little solid evi- Mayo Clinic and the National Center for Complementary and dence that ginkgo has real value in either improving memory Alternative Medicine – as well as specific references cited.
in older adults or helping to prevent dementia. Limited evi- Curcumin, a substance found in the spice turmeric dence suggests that the herb may improve memory and speed (Curcuma longa ). This supplement has been claimed to pro- of mental processing in healthy young or middle-aged people.
vide antioxidants for “good health,” as is stated in certainpromotional advertising, and to help relieve joint inflamma- Ginseng This is among the most popular of herbs, and it is tion. Limited clinical evidence suggests that it may have some used for a variety of reasons, the most common of which are value for the treatment of arthritis , ].
increased sense of well-being, stamina, and improved mentaland physical performance. As with several other herbal prod- Echinacea (Echinacea spp ) Products containing this herb have ucts, there are many conflicting studies regarding the medic- become popular for treating or preventing colds, flu, and other inal benefits of ginseng. One issue is that much of the infections. Echinacea appears to contain substances that stimulate supporting evidence rests on its use in traditional Asian med- the non-specific immune system , ], which is the probable icine over many centuries, and such anecdotal evidence is explanation for any benefit seen against infections. There have notoriously unreliable. Another major issue concerns the par- been several randomized double-blind controlled studies (RCTs), ticular species of ginseng being studied. There are several but results have not been consistent In some studies, the herb plants that are called ginseng, notably Asian ginseng (Panax was reported to shorten the duration of a cold by about half a day ginseng ) and Siberian ginseng (Eleutherococcus senticosus).
and to slightly reduce symptom severity, but in other studies no It seems likely that many products called “ginseng” are made benefit was observed. Based on this rather weak evidence, from cheap substitutes. Processing methods may also be an echinacea cannot be recommended for the treatment or preven- important source of variation between products. Overall, there is very little solid evidence that ginseng lives up to the manylofty claims of its efficacy ].
Evening Primrose Oil (Oenothera biennis ) This is used foreczema and other conditions involving inflammation, such as Goldenseal (Hydrastis canadensis) This is used for several rheumatoid arthritis. It is also used for conditions affecting disorders, particularly infections such as colds and other re- women’s health, such as breast pain associated with the men- spiratory tract infections. However, there is little solid evi- strual cycle, menopausal symptoms, and premenstrual syn- dence supporting its use for any health disorder drome (PMS). The herb appears to have no value in thetreatment of eczema but it may be useful for rheumatoid Milk Thistle (Silybum marianum ) This herb is claimed to arthritis and breast pain. Study results are mixed, however, have protective effects on the liver and to improve liver and most studies have been small and poorly designed ].
function. It is given as treatment for liver cirrhosis, chronic Evening primrose oil does not appear to affect menopausal hepatitis, and gallbladder disorders. Although there is some symptoms ], although a small study from Iran did report supporting evidence of efficacy, it is far from conclusive [].
improvements in hot flashes . The herb contains gamma-linolenic acid (GLA), an omega-6 essential fatty acid, which Saw Palmetto (Serenoa repens ) This is most commonly rec- appears to be the active ingredient.
ommended for treating benign prostatic hypertrophy (BPH).
Findings from clinical studies have been contradictory. The Ginkgo (Ginkgo biloba) This herb has gained much popular- ity based on claims that it improves the memory and may behelpful in the treatment or prevention of Alzheimer’s disease Sea Buckthorn This preparation contains omega-7 fatty acids and other types of dementia. Most trials that generated posi- that will, according to promotional advertising, help to retain tive findings were small and had a relatively short period of “healthy, vibrant young skin,” No relevant information could follow-up A large longitudinal study from France reported that persons who took a product containing ginkgo had aslower rate of cognitive decline []. However, as this study St. John’s Wort (Hypericum perforatum) In recent years, there was observational, there may have been errors caused by has been much interest in this herb as a treatment for mild to moderate depression, and it has been reported to have fewer systemic lupus erythematosus, multiple sclerosis, tuberculo- side effects than conventional drugs However, evidence as to its effectiveness is mixed. Several trials reported that the The above examples are probably just the tip of the iceberg.
herb was effective [], while other studies generated negative It is highly likely that only a small fraction of harmful side results []. Therefore, no definite conclusion is possible.
effects from the use of herbs are ever diagnosed and recorded The examples above illustrate a common story line with herbal products: a strong claim that the herb has importantbenefits, withsupporting evidence from a few studies, most of which are small and poorly designed, but failure to confirmthese results in larger, well-designed RCTs and other studies.
These substances are commonly used for the treatment of Unlike conventional drugs, herbal supplements generally osteoarthritis. Numerous RCTs have been carried out in which lack standardization of active ingredients, and there can be a glucosamine and chondroitin were tested on patients with great deal of variation between different brands of what is osteoarthritis of the knee or hip. The weight of evidence ostensibly the same herb due to factors such as the species of indicates that these supplements, either separately or in com- plant or part of the plant that is used and the extraction bination, do not bring about a clinically meaningful alleviation method. For example, there have been wide variations report- of joint pain or reversal of the narrowing of joint space ed in the concentration of active components among differentsamples of ginseng ] and St John’s wort It is alsoentirely possible that some manufacturers may simply be using cheap ingredients in place of expensive herbs. For thesereasons, an herb that was effective in a published study may be This product is sold in health food stores (HFS). According to the leaflet that accompanies it, Cellfood “enhances the bio-availability of oxygen though its ability to ‘dissociate’ watermolecules within the body – releasing nascent oxygen and hydrogen directly to the cells.” The ingredient list includesalmost the entire periodic table, even thallium, polonium, Some products comprise a dozen or so herbs, each with a nitrogen, and the inert gases. The only elements missing are Latin name. As very little research has been conducted on herb the ones well known to the general public as being toxic, such mixtures, there is no good reason to be confident that such as lead and arsenic. Other ingredients include 16 amino acids supplements will achieve any clinical benefit. Moreover, such and 32 enzymes. Despite this large number of substances, the herbal cocktails pose the risk of inducing harmful side effects recommended dose is a mere eight drops. The following that would be very difficult to relate to any specific herb or words were recently added to the product label: “World’s no.
herb combination. Polypharmacy is always hazardous, wheth- 1 selling oxygen & nutrient supplement.” Further comment is er it is based on conventional drugs or herbal cocktails.
Herbs often have harmful side effects. For example, the use of The obesity epidemic has given the supplement industry a perfect ginkgo has been linked to headaches, nausea, gastrointestinal opportunity to expand sales in a new direction. A wide variety of upset, diarrhea, dizziness, and allergic skin reactions []. Even dietary supplements are now marketed based on claims of in- more seriously, many deaths have been reported from the use ducing weight loss ], with advertisements that commonly of herbs Another potential hazard is an herb’s interaction display the photo of a woman with a BMI of about 21. In a with various drugs. This occurs most commonly with St detailed review of supplements that were being sold in the USA, John’s wort and to a lesser extent with ginkgo [The Sharpe and colleagues evaluated evidence of the effective- problem is exacerbated by the fact that supplement users often ness of the most commonly-used ingredients: green tea, chromi- fail to tell their physician that they are using a supplement. An um picolinate, ginger root (Zingiber officinale ), guarana American survey, for example, reported that among herbal (Paullinia cupana), white willow (Salix alba), Siberian ginseng, and dietary supplement users with chronic conditions, less cayenne (Capsicum annuum), and bitter orange/zhi shi (Citrus than 51 % disclosed the use of supplements to their healthcare aurantium). The investigators concluded that there was modest supporting evidence of the effectiveness of chromium and ginger Herbs can also be harmful to people with certain medical root, but they found evidence for the others to be inadequate or conditions. It is due to this concern that echinacea is contra- negative. In addition, there was evidence of potential harm from indicated for use among patients with rheumatoid arthritis, bitter orange and guarana. Trials using hydroxycitric acid (Garcinia cambogia ) have reported modest weight loss (an such case, the biomedical mechanism is so simple that the average person can quickly understand it. Such claims have Another herb that has been widely promoted for weight little credibility. Here are the three most common examples of loss in recent years is hoodia (Hoodia gordonii ). However, there is no evidence of its effectiveness, and little is known Many supplements, especially herbs, come with the claim that they stimulate the immune system. In a few cases, such asechinacea, there is supporting evidence, but in most cases, Another claim often used with herbal products is that they Acai (Euterpe oleracea), goji (Lycium barbarum, also known somehow accelerate the process of detoxification so that the as wolfberry), mangosteen (Garcinia mangostana), and noni body is cleansed. Detoxification is, of course, a well- (Morinda citrifolia) are marketed in the form of juices that are established process. However, claims that particular supple- often claimed to provide superior nutrition and enhanced ments induce detoxification and lead to enhanced health are health benefits. However, searches at Medline identified only a handful of clinical studies on these products, and they Many supplements are sold with the claim of being “rich in provide little evidence supporting the claimed benefits. For antioxidants.” It is true that many foods, such as fruits and example, in a review of mangosteen, the marketing claims vegetables, are naturally rich in antioxidants and are also excel- were found to be overstated and failed to disclose the “severe lent for maintaining good health. However, the relationship methodological weaknesses” of the cited research ]. A between foods, their antioxidant content as well as the presence clinical study on acai, while reporting positive results, was of other substances, and corresponding risk of disease is com- uncontrolled, included only 10 subjects, and lasted only a plex and not properly understood. In actuality, the connection month []. A study on goji reported a variety of benefits between intake of antioxidants and health outcome seems to be after only 14 days, but the study was carried out by a company quite weak. This is evidenced by the results of large RCTs in which β-carotene or vitamins C or E were tested and in which Despite the lack of credible evidence of health benefits, the dose used was typically several times higher than the RDA.
these juices are sold at exorbitant prices. Health food stores in Taken as a whole, the findings show no meaningful evidence of Canada charge about $50 to $60 per liter for them. By con- a reduced risk of cancer or heart disease. Indeed, a meta- trast, supermarkets sell common fruit and vegetable juices for analysis concluded that supplementing with these antioxidants led to an increase of approximately 2 % to 5 % in all-causemortality ]. Based on this evidence, it is therefore misleadingto assert that because a product is “rich in antioxidants,” it will The above overview shows that many of the claims com- The previous section showed that a wide variety of dietary monly used in the marketing of dietary supplements are either supplements are marketed in Canada and that they are sold for misleading or blatantly dishonest. The supplement industry is an equally wide variety of reasons. We will now look at the obviously exploiting the fact that most people have a weak common marketing claims designed to induce sales of sup- understanding of biomedical science.
plements, and a close examination reveals that a handful ofsuch claims occurs with great frequency.
In order for claims to have real credibility, we need to see consistent evidence from well-conducted RCTs with clinicalendpoints that show health benefits, and which are published We will now turn our attention to the most common methods in peer-reviewed journals. Such evidence, however, is seldom employed in the marketing of dietary supplements.
available. Instead, what we typically see is weak evidencepresented as if it were established fact. Examples of this are: Health Food Stores, Pharmacies, and Supermarkets (1) a particular herb that may have been used as a treatment forcenturies and therefore, it is argued, must be effective; (2) Health food stores (HFS) are a major source of dietary sup- evidence based on one or two studies that were small or poorly plements. There are several hundred such stores in Canada, designed; (3) anecdotal evidence, often from an unqualified and each typically sells a bewildering variety of supplements.
person with a serious conflict of interest; and (4) the use of Also, in recent years, most pharmacies and supermarkets have testimonials as a variation of anecdotal evidence.
given over substantial shelf space to supplements.
The marketers of supplements often make claims based on Several studies have reported that HFS staff often dispense physiological or biochemical changes in the body. In each highly misleading advice. Here we look at two Canadian studies. In one study, an investigator in Ontario posed as the containing substances in quantities so minute as to be harm- mother of a child with Crohn’s disease []. Of the 32 HFS less. The seller of this snake oil was promising potential visited, 23 (72 %) offered advice, and the advice was remark- customers that the product had two mutually exclusive fea- ably inconsistent, with 30 different herbs and nutritional sup- tures: a pharmacologically active dose of HGH, yet one that In a much larger study, visits were made to 260 HFS, Television is another common medium for the advertising pharmacies, and supermarket pharmacies across Canada of supplements. Often this is done as infomercials, which are The results reveal that when questions were asked of advertisements in the form of TV programs that are produced HFS staff, 88 % of the recommendations were either unscien- and paid for by commercial companies. Infomercials are tific (6 %) or were poorly supported by scientific literature typically 30 minutes in length and air during the night.
(82 %). By contrast, this occurred only 27 % of the time inpharmacies/supermarkets. Conversely, in two-thirds of visits to pharmacies/supermarkets, staff gave advice considered tobe accurate or fairly accurate, but this seldom occurred in HFS The multilevel marketing (MLM) strategy is used in a variety settings (68 % vs. 7 %). These findings reveal a major differ- of product sales, such as Avon cosmetics and Tupperware, in ence between HFS and the supplement sections of a pharma- which company salespeople recruit additional salespeople, cies or supermarkets. In the latter, customersrequesting advice who then sell direct to the public on a commission basis.
are far less likely to be advised to buy useless supplements.
MLM is often used by dietary supplement manufacturers, This is not surprising, as pharmacists are trained health pro- and its focus is profit, not consumer health. Based on my fessionals and must abide by a code of ethics.
own observations, few MLM salespeople hired to sell supple- The following a realistic HFS scenario. A middle-aged man ments have any real training in nutrition.
tells the salesperson that he would like to have more energy, that Here is one example of MLM in action. In 2007, advertis- he sometimes forgets things, has an ache in his knee, and that his ing leaflets were distributed in Edmonton promoting a public father died of cancer. He will probably be advised to take a lecture by Dr. Earl Mindell. The goal was to recruit persons to handful of supplements, each costing between $20 and $60 per sell goji juice. The leaflet referred to Mindell as “widely month. This could easily add up to between $100 and $200 per regarded as the world’s #1 nutritionist” and the product as month, and it is quite likely that the recommended supplements “the biggest discovery in nutrition in the last 40 years.” Both will have little or no beneficial effect on his health.
statements were enormous exaggerations.
MLM appears to have become much less prevalent in the last few years. Presumably, it is not generating the desiredsales volume, and print media advertising is clearly now the Newspapers and magazines are major marketing tools for supplement sales. The Edmonton Journal, for example, regu-larly includes four- or eight-page supplement advertising in- serts, and readers wishing to buy supplements are then direct-ed to either HFS or Internet websites.
The Internet is a tool perfectly suited to the marketing of dietary Newspapers occasionally carry advertisements for a single supplements. There are a great many websites that sell supple- supplement, as illustrated in the following example. The Ed- ments, and they send out millions of spam e-mails. However, as monton Journal recently carried a full-page advertisement for very few of these websites are based in Canada, the Internet a supplement called Soma HGH. In large print, the headline marketing strategy is beyond the focus of this paper.
stated: “Experts in the New England Journal of Medicine,Science, Newsweek, Time, and more report human growthhormone makes you look and feel 20 years younger.” Most of Regulations on the Marketing of Supplements the page consisted of a detailed account of the fantastic ben-efits of the human growth hormone (HGH). But buried deep The dietary supplement industry poses many regulatory chal- within the advertisement was an indication of what was really being sold. It read: “The 17 botanical extracts combined in In 1999, the Canadian federal health department, Health Soma HGH are prepared in accordance with the Homeopathic Canada, created the Natural Health Products Directorate, an Pharmacopoeia of the United States and are recognized as organization designed to regulate dietary supplements official medicines….They ….have none of the dangerous or The directorate’s mission is to ensure that Canadians have unpleasant side effects of synthetic drugs. They are among the access to natural health products (NHP) that are safe, effective, safest preparations known to medical science.” In other words, and of high quality. All manufacturers, importers, packagers, what was being sold was not HGH, but a supplement and labelers of NHP must now have site licenses, and any new NHP must have a product license. The regulations require a much advertising is likely to be false or misleading, and warn pre-market review of products to assure Canadians that label that many supplements, especially herbs, may pose a risk of information is truthful and that health claims are supported by harm, either directly or by interacting with prescription drugs.
the appropriate scientific evidence.
The evidence examined here reveals that regulatory agen- The announcement of these regulations gave the clear cies have badly failed in their mission.
impression that there would be greater honesty in the market-ing of supplements. In other words, a bottle of herb X sold in Canada should now contain the amount of the herb stated onthe label. Furthermore, if marketers claim that herb X detox- Norman J. Temple has received book sale royalties ifies a person, then there must be good evidence to substanti- from Humana Press, Inc. (Springer), and has received payment for lectures,including service on speakers bureaus, and has been reimbursed for travel/ accommodations/meeting expenses by Saskatchewan University.
After the 1999 announcement, the supplement industry was then given several years to implement the regulations, Human and Animal Rights and Informed Consent which came into force in January 2004. At the time of this not contain any studies with human or animal subjects performed by any writing (July 2013), the regulations have been in force for nine years, but as has been documented in this paper, dishonestmarketing is still very widespread. The regulators appear to beasleep at the controls.
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