Health Studies 301 Complementary and Alternative Therapies

Study Guide: Unit 11

Alternative Approaches to Diet and Nutrition

Spirulina (dietary supplement) tablets. Perdita, 2006 English Wikipedia, Public Domain.

Nutrition is a rapidly developing science, with new discoveries being continually reported and new theories generated about its role in disease and health.

Practitioners of complementary and alternative medicine often promote diet regimens that have not been scientifically proven to prevent or cure disease. Often they recommend very high levels of nutrients. This unit examines alternative theories of nutrition and disease as well as some commonly recommended nutritional supplements.

Learning Objectives

Upon completion of Unit 11, you should be able to

• discuss the appropriate use of dietary supplements and of alternative diet regimens.
• identify situations where alternative approaches to diet and nutrition are commonly used.
• determine the effectiveness of alternative approaches to diet and nutrition by analyzing the available research.
• identify trends and issues related to alternative diet therapies.

Learning Activities

Study Questions

As you complete the activities for Unit 11, keep the following questions in mind. You may want to use the Personal Learning Space wiki on the course home page to answer these questions as a way of keeping notes to focus your learning.

1. What do Canada’s Food Guide and similar guides for other countries advocate? Have these guides changed over the years? What might account for such changes?
2. What supplements have been shown by reliable research studies to have substantial benefits?
3. What supplements may be dangerous to health?

Unit 11 Discussion Forum

When you have completed the other activities for this unit, answer at least one of the questions in the Unit 11 Discussion Forum and respond to at least one post by a fellow learner.

The more questions you answer, the better prepared you will be for the final exam!

Nutritional Therapies

Practitioners of several types of CAM therapy have integrated nutritional therapies into their practice. Naturopaths, in particular, routinely employ nutrition treatments, both for prevention and for therapy.

Nutrition information intended for the prevention and treatment of disease can be divided into three types:

1. that which is firmly supported by published evidence, which can be recommended to the public, and which is used by dietitians, physicians, and other health professionals.
2. that which is more controversial but deserves to be taken seriously.
3. that which can be best characterized as food faddism or consumer fraud.

Unfortunately, there is no clear division between these three types of nutrition information. Many health service providers use nutrition techniques that are supported by less than convincing evidence. At times, this can be justified because the therapy is arguably the best that is available and is unlikely to do harm. However, many CAM practitioners are promoting nutritional supplements or diets that have no scientific basis and could be harmful in the long run.

Dietary Recommendations

There are a number of sets of dietary recommendations.

Canada’s Food Guide

In January 2019, the latest edition of Canada’s Food Guide was released by Health Canada. Although the food guide has undergone different looks, new names, and new messages, the general objective has always been guiding food selection and promotion of nutritional wellbeing of the Canadian population.

Canada’s Food Guide describes a healthy diet. Following the diet will help people

• get enough vitamins, minerals, and other nutrients.
• reduce the risk of obesity, type 2 diabetes, heart disease, certain types of cancer, and osteoporosis.
• achieve overall health and vitality.

The diet is based on extensive scientific evidence. It was developed by looking at different combinations of amounts and types of food to find an eating pattern that meets nutrient needs. The diet was also evaluated against evidence that links certain foods with reduced risk of chronic diseases.

The new food guide is entirely online and can be accessed by clicking on this link:  https://food-guide.canada.ca/en/

The new Canada’s Food Guide has undergone a substantial transformation from all previous versions. The previous guide placed meats and alternatives in one food group and milk and alternatives in another. The new food guide places these foods into one food group, known as protein foods. Another major change is that the new food guide does not state the recommended amounts of foods. The new guide recognizes that healthy eating is more than the foods you eat. It is about where, when, and why you eat. Another significant change is its entirely digital web-based format. Canada’s Food Guide can now be easily accessed from any mobile device and is highly interactive and colourful.

The new Canada’s Food Guide is represented as one image—the Eat Well Plate.

Key messages are as follows:

• Eat plenty of vegetables and fruits, whole grains, and protein foods. Choose protein foods of plant origin, rather than animal origin, more often.
• Choose foods with healthy fats. Healthy fats are unsaturated fats such as olive, canola, peanut, sesame, soybean, flaxseed, safflower, and sunflower. Foods containing unsaturated fats include nuts, seeds, avocado, fatty fish, vegetable oils, and soft margarine.
• Limit highly processed foods. If you choose these foods, eat them less often and in small amounts.

Recommendations for Nutrient Intake

The dietary reference intakes (DRI) were developed in the late 1990s jointly by the United States and Canada. The recommended dietary allowances (RDAs) are estimates of the daily amounts of nutrients considered necessary to meet the needs of most healthy people. For those nutrients where there is insufficient information to establish an RDA, less exact estimates, known as adequate intake (AI), are made. Values of RDA and AI are given for 14 vitamins, 15 minerals, energy, carbohydrates, essential fatty acids (omega-3 and omega-6 polyunsaturated fatty acids), protein, dietary fibre, and water. Tables are broken down by age and sex. Specific recommendations are given for women who are pregnant or lactating.

Another table within the DRI is the Tolerable Upper Intake Level (UL). The UL is the maximum amount of potentially toxic nutrients that appears safe for most healthy people to consume on a regular basis. Whereas RDA and AI are targets to aim for, UL provides a warning against overconsumption of nutrients.

Problems with the Canadian Diet

If everyone followed the recommendations given in Canada’s Food Guide, intake of almost all nutrients would be within the ideal range. Moreover, intake of dietary fibre and of other dietary components would also be adequate. As a result we would see much lower rates of chronic health problems such as CHD, cancer, type 2 diabetes, obesity, and hypertension.

Unfortunately, the diet eaten by much of the population has major problems. We can summarize the key problems as follows:

1. The diet has an inadequate content of fruit, vegetables, and whole grain cereals. At the same time, it contains excessive amounts of sugar, refined cereals, and unhealthy fats, especially saturated fatty acids. The net result of all this is that the typical diet has a high energy density, i.e., a high content of energy (kcal) per gram. This induces an excessive energy intake, which then leads to obesity and all the associated problems.

   Conditions closely associated with obesity include hypertension (a major risk factor for CHD and stroke), type 2 diabetes, and several forms of cancer (such as cancer of the colon and breast). Overnutrition is possibly the biggest single nutritional problem in Canada.

2. The diet is often inadequate in several key nutrients, such as vitamin A (Kirkpatrick & Tarasuk, 2008). One major reason for this is that the typical Canadian diet has inadequate amounts of foods rich in vitamins and minerals, most notably fruit, vegetables, and whole grain cereals.

3. In addition, women often have an inadequate intake of potassium, calcium, iron, folate, and vitamin B6 (Kirkpatrick & Tarasuk, 2008). The RDA for calcium is 1200 mg for adults aged over 50. This is equivalent to a litre of milk. But large numbers of women have a low intake of milk and of other calcium-rich foods. This problem is most likely to occur in non-Caucasians, as the majority of them have lactose intolerance.

   A survey in Canada revealed that a quarter of women have a calcium intake of under 500 mg per day (Gray-Donald, Jacobs-Starkey, & Johnson-Down, 2000). Body stores of iron are often low among pre-menopausal women. An inadequate intake of folate is caused by a low intake of fruit, vegetables, and whole grain cereals. However, since 1998 refined cereals have been “fortified” with folic acid, and as a result, inadequate folate has been much reduced (but not eliminated).

4. Most people have a rather low intake of several other essential substances found in the diet including dietary fibre (Kirkpatrick & Tarasuk, 2008) and omega-3 fatty acids.
5. One particular problem is vitamin D. Milk in Canada is fortified with this nutrient. Fish is another good source. But if milk and fish consumption is low, then vitamin D status may be poor, since there are few other significant dietary sources. There is good evidence that much of the Canadian population has an inadequate intake. The primary problem here is lack of ultraviolet light from sunshine for much of the year because of Canada’s northern location. Vitamin D insufficiency is most common in the elderly, people with dark skin, and those who expose little skin to the sun.
6. The dietary problems listed above are considerably worse among people living in poverty (Kirkpatrick & Tarasuk, 2008).
7. Another important dietary problem is sodium, but here the problem is an excessive intake. A high dietary intake of sodium is one of several factors that play an important role in the development of hypertension.

Do we need dietary supplements?

An Overview of the Use of Dietary Supplements

Around half the population of Canada regularly uses dietary supplements. There are many different supplements, and they are used for many reasons. Here we examine different types of dietary supplements and whether their use is justified.

Vitamins and minerals are, of course, essential to health. It is generally accepted that for the great majority of healthy individuals, the required amount of vitamins and minerals can be obtained by eating a diet based on Canada’s Food Guide. Obtaining vitamins and minerals from food has the outstanding advantage that these substances are present in the right balance together with the many other substances found in food, including fibre and essential fats.

Research in recent years on phytochemicals has added much strong evidence for the importance of a healthy diet. These substances are organic, but as they are non-essential, they cannot be classified as vitamins. There are thousands of different phytochemicals present in food. Examples include lycopene (the red substance in tomatoes and watermelon) and lutein (found in dark green vegetables). Much research suggests that phytochemicals have a protective action against disease. Because there are so many different phytochemicals and our knowledge of them is still weak, the only practical way to obtain them is from food, not supplements. In other words, a healthy diet supplies a vast variety of phytochemicals in the right amounts and in the right balance whereas supplements supply, at most, only two or three phytochemicals.

Dietary Supplements: Examples with Moderate or Strong Supporting Evidence

While a healthy diet is the preferred way to obtain an adequate intake of vitamins and minerals, the reality is that most Canadians eat a rather unhealthy diet and therefore have a low intake of several key nutrients. As a result, dietary supplements can play a valuable role in improving the intake of several nutrients. The evidence is strongest for people whose diets are marginally deficient and in such groups as pregnant women and the elderly. The argument for using supplements is strongest in the following cases:

1. Folic acid. Canada’s Food Guide recommends that all women who could become pregnant and those who are pregnant or breastfeeding take a multivitamin containing folic acid. The rationale for this is that randomized controlled trials (RCTs) have demonstrated that supplements of folic acid can prevent a substantial proportion of neural tube defects (NTDs) such as spina bifida (MRC Vitamin Study Research Group, 1991).
2. Vitamin D. A low intake and low blood levels of vitamin D are closely associated with various health problems.
   • Some evidence has suggested that vitamin D is protective against fractures. The presumed mechanism is by enhancing absorption of calcium. However, the evidence, taken as a whole, is mixed and inconclusive (Theodoratou E, Tzoulak, Zgaga, & Ioannidis, 2014; Bischoff-Ferrari, Willett, Orav, Lips, et al., 2012).
   • Evidence has also emerged that vitamin D may play a significant role in the prevention of several diseases, including cardiovascular disease and cancer, especially colon cancer (Scragg, 2011; Chowdhury, Kunutsor, Vitezova, Oliver-Williams, et al., 2014). The vitamin may also help lower total mortality (Theodoratou E, Tzoulak, Zgaga, & Ioannidis, 2014).

   The ideal dose for prevention is higher than the RDA (15 μg or 600 IU per day for ages up to 70, and 20 μg or 800 IU per day for over age 70). Taking the evidence as a whole, there is a good case for a daily supplement containing 25 μg (or 1000 IU) per day for such groups as the elderly, people with dark skin, and those who expose little skin to the sun (Chowdhury, Kunutsor, Vitezova, Oliver-Williams, et al., 2014). (Note: μg is the abbreviation for micrograms).

   It must be stressed that this whole area is controversial. As yet, there is no solid evidence from randomized controlled trials that supplements of vitamin D do indeed deliver health benefits. As mentioned above, Canada’s Food Guide recommends that all adults over age 50 in Canada should take a vitamin D supplement, though at a lower dose than that suggested here. You should be aware that the potent form of vitamin D is D3.

3. Multivitamins. A substantial fraction of the population eats a diet that is far from ideal. For that reason, a case can be made for a general recommendation to take a daily multivitamin, at least for specific population groups. Willett and Stampfer (2001) summarized this argument as follows:

   A multivitamin is especially important for women who might become pregnant; for persons who regularly consume one or two alcoholic drinks per day; for the elderly, who tend to absorb vitamin B12 poorly and are often deficient in vitamin D; for vegans, who require supplemental vitamin B12; and for poor urban residents, who may be unable to afford adequate intakes of fruit and vegetables.

   What should a multivitamin pill contain? Many women in their reproductive years require extra folic acid and iron, especially if they are pregnant. As stated above, the elderly and vegans are often short of vitamin B12. Generally, the content of vitamin D in multivitamin pills is well below the amount suggested earlier; an extra pill is therefore required.

   Despite this suggestive evidence, there is only a weak case for a blanket recommendation that the bulk of the population consume a multivitamin daily (i.e., a one-a-day pill containing most vitamins and minerals at approximately the RDA). Indeed, there is remarkably little evidence to indicate that such a pill enhances health. We see this most clearly in the findings from randomized controlled trials. Several such trials have taken place to determine whether multivitamins have any value in the areas of all-cause mortality, cardiovascular disease, cancer, or cognitive impairment. A paper published in 2013 in the journal Annals of Internal Medicine summarized the findings and drew a firmly negative conclusion (Guallar, Stranges, Mulrow, Appel, & Miller, 2013). The paper had the unambiguous title: “Enough is enough: Stop wasting money on vitamin and mineral supplements.”

4. Fish oil. Much research evidence has revealed that eating fish (especially fatty fish) between one and five times per week is associated with a reduced risk of CHD, especially fatal CHD (Slmomski, 2011; Van Horn et al., 2008). Fish oil displays the same protective association. The cardioprotective benefits of fish and fish oil appear to be greater in populations at higher risk of developing CHD and in those that habitually consume only small amounts of fish.

   The active ingredient in fish and fish oil responsible for these benefits is omega-3 fatty acids. Although several types of plant oil also contain omega-3 fatty acids, it is the long-chain type found in fish, namely EPA and DHA, that appears to be especially potent.

   This evidence makes a strong case that fish is likely to have a protective action against the risk of CHD. For a person who chooses not to eat fish regularly, fish oil supplements may provide much of the benefit. However, this has not as yet been firmly established.

Dietary Supplements: Examples with Weak or Non-Existent Supporting Evidence

We now look at examples—and there are many to choose from—where the supporting evidence is weak or non-existent. In each of these cases, there is no legitimate reason for a health professional (or anyone else) to recommend its use.

1. Megadoses of vitamins (orthomolecular medicine). For several decades, the idea has been advocated that megadoses of various vitamins are required in order to achieve optimal health.

   The concept is most closely associated with Linus Pauling, who coined the term “orthomolecular medicine” in 1968. In this therapy, not only vitamins but also minerals, amino acids, trace elements, and fatty acids are given, often in high doses. The therapy “aims to restore the optimum environment of the body by correcting imbalances or deficiencies based on individual biochemistry” (https://isom.ca/).

   Pauling is best known for his claim that megadoses of vitamin C can both prevent and treat the common cold. The claim was made in his best-selling book Vitamin C and the Common Cold. Pauling argued that humans need one gram or more per day, an amount that is many times more than the RDA (75 to 90 mg per day). He extended the concept to the prevention and treatment of cancer.

   Randomized controlled trials were carried out to test Pauling’s hypotheses, but the results have been largely negative. At most, a high dose of vitamin C may have a minor benefit on the duration of a cold. The whole concept of megadose vitamin therapy has been all but rejected by conventional physicians and nutritionists. Nevertheless, the belief endures that people who have a cold should take high doses of vitamin C.

2. Antioxidant vitamins. Vitamin C is a type of nutrient called an antioxidant. The other major antioxidant vitamins are beta-carotene and vitamin E. There are hundreds of other substances that act as antioxidants but that are not vitamins. Antioxidants scavenge free radicals, thereby preventing the cellular damage they cause. In theory, this should prevent disease. Many epidemiological studies have been published showing that people with a relatively high intake of the three antioxidant vitamins have a lower than average risk of such chronic diseases as CHD and cancer. The obvious implication of these findings is that supplements of antioxidant vitamins will protect against CHD and cancer.

   Several large RCTs have been conducted in which the major antioxidant vitamins have been tested. Most RCTs have focused on beta-carotene or vitamin E; only a few have looked at vitamin C. The major goal of most trials has been the prevention of either CHD or cancer. The dose has typically been several times higher than the RDA. Meta-analyses have revealed that supplements of the antioxidant vitamins fail to prevent either CHD or cancer (Druesne-Pecollo et al., 2010; Vivekananthan, Penn, Sapp, Hsu, & Topol, 2003). Moreover, a major meta-analysis concluded that supplementing with beta-carotene or vitamins C or E leads to an increase of about 2% to 5% in all-cause mortality (Bjelakovic, Nikolova, Gluud, Simonetti, & Gluud 2012).

   Taking the above evidence as a whole, we can reasonably conclude that while foods naturally rich in antioxidants and phytochemicals, such as fruit and vegetables, are excellent for the health, this benefit does not extend to purified antioxidants (Temple, 2000). The reasons for this are complex and poorly understood.

   The saga of antioxidant vitamins serves as a reminder that we must always be cautious when making claims about the benefits of dietary supplements. What may appear to be a strong case for the value of a particular dietary supplement can collapse once the results of RCTs become available and we find that the supplement fails to deliver the promised health benefits.

3. Vitamins and blood homocysteine. This is another story in the history of dietary supplements that has several similarities to the story of antioxidants. A number of studies revealed that the blood level of homocysteine predicts the risk of CHD (Humphrey, Fu, Rogers, Freeman, & Helfand, 2008). This suggests that lowering the blood level of homocysteine will help prevent CHD, much like lowering the blood level of cholesterol. It was also discovered that three of the B vitamins—folic acid and vitamins B6 and B12—are effective for this purpose. This led to the prediction that supplements of these vitamins would prevent CHD. Several RCTs were carried out, but they found essentially no beneficial impact on risk of CHD (Clarke, Halsey, Bennett, & Lewington, 2011).

We now turn from vitamins to other types of dietary supplements. A wide variety of products are being sold with claims of enhancing health. Here we look at a handful of examples. The ones selected are fairly popular and illustrate the different types of supplements.

1. Probiotics. These are live microorganisms, usually bacteria or yeast, present in fermented foods. They are sold with the claim that they improve the balance of intestinal microflora and inhibit the growth of pathogenic bacteria. Yogurt containing live lactobacilli is, in reality, a probiotic; it has been popular in parts of Europe for centuries.

   Probiotics have been tested on people suffering with a number of health problems, mostly intestinal (Aureli et al., 2011; Weichselbaum, 2010). Positive results have been reported in several studies. Improvement has been seen in sufferers from constipation, some types of diarrhea (especially the type associated with use of antibiotics), and irritable bowel syndrome. Positive results have also been seen for people with depression (Huang, Wang, & Hu, 2016).

   However, it is premature to start recommending use of probiotics for the general population. First, most research has been conducted on people with a health condition with a goal of helping to cure the problem, whereas most marketing is directed at healthy people. Second, probiotics are often given as part of a food, such as yogurt, but at a dose too low to achieve the intended benefits (Scourboutakos et al., 2017). Third, a huge variety of living microorganisms are used in probiotics. We cannot assume that positive results seen with one particular preparation will be reproduced by a different preparation. We saw a similar problem in Unit 10, when we examined herbal products.

2. Coenzyme Q10 (CoQ10). This is a naturally occurring vitamin-like substance found throughout the body, but especially in the heart and liver. It is eaten in small amounts in meat and seafood. It is used by many CAM practitioners for treating heart and blood vessel conditions such as congestive heart failure (CHF), chest pain (angina), and high blood pressure. However, despite its popularity and the many claims made for it, the supporting evidence for the efficacy of this supplement is quite meagre. There is some evidence that it may cause a small lowering of the blood pressure. Also, it may help in the treatment of CHF when used together with other treatments.
3. 1. Glucosamine. This is a natural amino sugar found in healthy cartilage. It is widely used for the treatment of osteoarthritis, the most common type of arthritis. It is often claimed that it enhances the strength of the cartilage while improving the composition of the synovial fluid. Various side effects have occasionally been reported.

   2. Chondroitin (chondroitin sulfate). This is a complex carbohydrate that helps cartilage retain water. It is extracted from sources of cartilage, such as shark. Like glucosamine, chondroitin is used to treat osteoarthritis. RCTs indicate that it is safe.

      Numerous RCTs have been carried out where glucosamine and chondroitin have been tested on patients with osteoarthritis of the knee or hip. The weight of evidence indicates that these supplements, either separately or in combination, do not reduce joint pain (Wandel et al., 2010).

4. CellFood. This is a product sold in health food stores. The ingredient list states that it contains almost every one of the 92 elements, even nitrogen and the inert gases. The only elements missing are the ones well known to be poisonous, such as arsenic and lead; even thallium and polonium are included, although both are poisonous. The product also contains 16 amino acids and 32 enzymes.

   The accompanying leaflet makes the following claim: “[CellFood] enhances the bioavailability of oxygen through its ability to ‘dissociate’ water molecules within the body—releasing nascent oxygen and hydrogen directly to the cells.” Quite remarkably, despite being loaded with such a wide assortment of active ingredients, the recommended dose is a mere eight drops.

   Clearly, the claims made for this product are devoid of credibility. Despite that, the website proudly claims it is the “World’s no. 1 selling oxygen + nutrient supplement” (http://www.cellfood.com/).

5. Exotic fruit juices. Among the great variety of products to be found in health food stores are several types of what can be best called exotic fruit juices. These include juices from acai, goji, mangosteen, and noni. Whereas the common juices such as orange, grape, apple, and vegetable juice cost around $2 to $3 per litre, the exotic ones typically cost $50 to $60 per litre. Despite the very high price, there is no good evidence that they have any special health benefit.
6. Weight-loss products. Health food stores also sell a range of products claimed to help bring about weight loss. Green tea does have modest effectiveness (Thavanesan, 2011), as does chromium picolinate (Sharpe et al. 2006). However, there is little or no supporting evidence for other commonly used ingredients in products claiming to help with weight loss, including guarana, hydroxycitric acid (Garcinia cambogia), and bitter orange (Citrus aurantium) (Sharpe, Granner, Conway, Ainsworth, & Dobre, 2006). The weakness of the supporting evidence is supported by much expert opinion (Medline Plus, https://medlineplus.gov and National Center for Complementary, Alternative, and Integrative Medicine, https://nccih.nih.gov).
7. Sex-related products. Where there is a potential market, manufacturers will concoct supplements to expand sales. As with supplements that promise weight loss, manufacturers have energetically marketed supplements that promise to enhance sexual performance, usually for men. The range of products is wide, while the effectiveness is probably minimal.

Potential Hazards from Supplements

The supplement industry regularly boasts that its products are safe. Alas, this is often not the case. Several examples of real dangers posed by supplements have already been given, both in this unit and in the previous one on herbal products. There have been many cases of supplements containing undeclared active pharmaceutical agents. Cohen (2009), in an editorial in the New England Journal of Medicine, wrote that “more than 140 contaminated products have been identified [in the United States], but these represent only a fraction of the contaminated supplements on the market.”

There have been numerous documented cases of supplements found to be contaminated with medications. This seems to occur most often with supplements promoted for sexual enhancement, improved athletic performance, or weight loss (Cohen, 2009). Alarming findings came from a study in which a chemical analysis was conducted on traditional ayurvedic medicines that were being sold in the United States via the internet. The findings revealed that 21% of these herbal preparations exceeded one or more standards for acceptable daily intake of lead, mercury, or arsenic (Saper et al., 2008).

The Marketing of Dietary Supplements

As should now be clear, there are a great many dietary supplements available to the general public. A few have strong supporting evidence that they do deliver the promised benefits, while many others have supporting scientific evidence that ranges from weak to non-existent. Nevertheless, the manufacturers and sellers of supplements have shown no hesitation in using all available means to maximize sales. Here we examine how they do that. Since herbal products are sold alongside dietary supplements and are marketed using the same methods, this discussion includes both types of products.

A feature repeatedly seen when supplements are being promoted is the claim that the supplement brings about a favourable change in body function. However, this is invariably based on what can best be described as a super-simple version of human biochemistry and physiology. In particular, three mechanisms of action of supplements appear again and again:

• The supplement is rich in antioxidants. Antioxidants, it is often claimed, prevent disease by scavenging free radicals, thereby preventing cellular damage. RCTs referred to earlier demonstrate a complete lack of benefit from taking supplements of the three major antioxidants (beta-carotene and vitamins C and E).
• The supplement brings about detoxification. Herbal treatments in particular are often sold with the claim that they will stimulate the liver—and perhaps some other organs as well—so that detoxification is accelerated and the body is cleansed. The serious flaws with this claim were discussed in Unit 9 (Naturopathy).
• The supplement boosts the immune system. As with detoxification, this is usually associated with herbs. There is evidence that a few herbs, notably echinacea and ginseng, have this capability, but the marketers make claims far beyond what has been firmly established.

Making claims for the effectiveness of supplements based on super-simple mechanisms creates the illusion that the supplement has a favourable effect on body functioning, while the explanation can be easily understood by anyone with a grade 10 education. Super-simple mechanisms have been used many times over the decades to explain health problems and to justify unscientific treatments. In the 1970s, a common diagnosis was hypoglycemia. This was an instant explanation for tiredness and an array of other vague symptoms. Rarely was the diagnosis confirmed by measuring the blood glucose level. An intestinal yeast infection provides a similar example. During the 1980s this was a popular explanation for diverse health problems.

Newspaper ads are an increasingly common form of supplement marketing. The examples given below come from the Edmonton Journal, but the same is doubtless true for other major cities across Canada.

Every one or two weeks, the Edmonton Journal contains an advertising supplement comprising eight or ten pages of advertising for herbal and dietary supplements. Claims are made for each product. However, based on the evidence reviewed in this unit and the previous one, many of the claims are a huge exaggeration of weak evidence. Here are some examples of seriously distorted claims made in ads:

• “Clinical human studies show . . . [vitamin] B12 can reduce homocysteine levels, reducing the risk of heart disease, stroke.”
• “Vitamin E . . . is important for cardiovascular health and is a powerful antioxidant that protects against damage caused by free radicals.”
• “ginkgo [helps improve] the early stages of Alzheimer’s disease.”

An especially outrageous advert for human growth hormone (HGH) appeared in the Edmonton Journal several times during 2012. An entire page was given to explaining the many wonderful benefits that would come from boosting the body’s level of HGH. But buried deep in the ad was the following short statement:

The 17 botanical extracts combined in Soma HGH are prepared in accordance with the Homeopathic Pharmacopedia of the United States and are recognized as official medicines . . . . They . . . have none of the dangerous or unpleasant side effects of synthetic drugs. They are among the safest preparations known to medical science.

This statement tells the reader three things: First, the product is a plant (botanical) extract. Plants do not contain HGH or any other human hormone. In other words, the supplement is not HGH! Second, the supplement is based on homeopathic principles. As will be explained in the following unit, homeopathic medicines contain extremely low doses of bioactive substances. Third, the product is extremely safe. Were the product actually a hormone, then it would certainly pose at least some risk (all hormone treatments have at least some adverse effects). However, since the product is nothing more than a minute dose of a plant extract, the sellers can make the claim of total safety. In other words, taking the product is not much different from taking a few drops of orange juice! And for that customers must pay $230 for a six-month supply.

In addition to advertising for supplements in newspapers, many ads appear on TV, often for weight-loss products or for probiotics.

We now turn to the direct sale of supplements. Health food stores are a popular source of dietary supplements. They typically carry hundreds of different products. Drugstores and the pharmacy section of supermarkets also sell many types of supplement.

A large study was carried out in Canada to determine whether customers are being given honest and accurate advice (Temple, Eley, & Nowrouzi, 2009). Visits were made to 260 health food stores and drugstores (or the pharmacy section of supermarkets). In each case, a student posed as a customer and asked for advice on the use of a supplement. The results reveal that 88% of the times that questions were asked in health food stores, the recommendations made were either unscientific (6%) or poorly supported by the scientific literature (82%). By contrast, this occurred for only 27% of questions in drugstores/supermarkets. Conversely, on two-thirds of visits to drugstores/supermarkets, staff gave advice considered to be fairly accurate or accurate, but this seldom occurred in health food stores (68% versus 7%).

The findings clearly show that health food stores are an extremely unreliable source of information on the use of supplements. But customers requesting advice in drugstores/supermarkets are far less likely to be encouraged to buy useless supplements. This is not surprising, as pharmacists are trained health professionals and must abide by a code of ethics.

The purpose of all this marketing of supplements, whether by advertising or in health food stores, is, of course, to maximize sales. As mentioned earlier, there are some supplements for which there is reasonably solid supporting evidence. Examples include folic acid and vitamin  D; these cost approximately $3 or $4 per month.

But let us suppose that a potential customer seeks advice in a health food store. The customer, a typical middle-aged Canadian, might seek advice for such widespread problems as insufficient energy, a poor memory, needing to lose weight, and fear of developing cancer. The likely result is to be advised to take several different supplements, each costing around $20 to $60 per month. The total cost could easily be $100 to $200 per month. And what health benefit would the customer get in return if he or she chose to follow the advice? Probably little or none.

Canadian Regulations on the Marketing of Dietary Supplements

In theory, dietary supplements sold in Canada are subject to strict regulations. Supplements are classed as natural health products (NHPs), a group of products that includes dietary supplements (e.g., vitamins, minerals, and probiotics) as well as herbal products and homeopathic medicines. The Natural and Non-prescription Health Products Directorate (NNHPD), a section of Health Canada, has the job of ensuring that Canadians have access to NHPs that are safe, effective, and of high quality (Health Canada, 2011b).

The regulations require a pre-market review of products to confirm that label information is truthful and that health claims are supported by appropriate types of scientific evidence. Here is a statement from the Health Canada website (Health Canada, 2011b): “The safety and efficacy of NHPs and their health claims must be supported by proper evidence so that consumers and Health Canada know the products are indeed safe and effective.”

On paper, the new regulations appear to be a big step forward. If the regulations were properly followed, then packages of supplements would now contain what the label says they contain. Moreover, Canadians would be protected from dishonest marketing. Much evidence reveals that the new regulations have badly failed to achieve their stated goals. As documented above, Canadians are still being continually exposed to widespread false advertising of supplements. Moreover, there is evidence that many herbal products do not contain what is stated on the label (Temple, 2016).

Alternative Approaches to Diet and Nutrition

We now move from the use of dietary supplements to other alternative approaches to diet and nutrition. The range of ideas being advocated and of treatments being offered is bewilderingly diverse. Moreover, the whole area changes at a rapid rate. For those reasons, it is not possible to present more than a few representative examples. Particular attention will be paid to those preventative and therapeutic approaches that have been most widely adopted, either by CAM practitioners or the general public.

Fasting

Unit 9 discussed the practice of fasting as a therapy used by naturopaths. Fasting is advocated based on the rationale that it induces “detoxification.” Many people believe that occasional fasting for a day, perhaps with the consumption of juices, somehow “cleans” the body. However, there is no credible evidence that detoxification can be induced by fasting or that fasting has any beneficial effects on health. Moreover, as stated in Unit 9, fasting may be detrimental in certain conditions and may even be life threatening if it takes place over a long period of time.

Vegetarianism

Once chosen as a path to spiritual purity, the practice of vegetarianism is now adopted for a variety of reasons, including health and ecological concerns. The following are the most common forms of vegetarian diets:

• A macrobiotic diet is a limited diet. Its purpose is to achieve a balance of yin and yang in order to fend off disease (see textbook, page 436). Extreme forms of the diet can be very restrictive, consisting of only brown rice and herbal teas.
• A vegan diet excludes all foods of animal origin.
• Lacto-vegetarians include milk and milk products, but omit all other animal sources of food.
• Lacto-ovo-vegetarians consume milk, milk products, and eggs as animal sources of protein.

The key feature of all vegetarian diets is the absence of meat as well as of fish. At the same time, vegetarian diets typically have a high consumption of fruit, vegetables, grains, legumes, and beans, each of which may be independently associated with a positive health outcome.

Consumption of red meat (which usually means pork and beef) has been linked to risk of cardiovascular disease, type 2 diabetes, and some types of cancer, especially colon cancer (McEvoy, Temple, & Woodside, 2012; Micha, Wallace, & Mozaffarian, 2010; World Cancer Research Fund, 2018; Sinha, Cross, Graubard, Leitzmann, & Schatzkin, 2009). The relationship is generally strongest for intake of processed meat such as bacon, ham, and sausage.

Vegetarian diets that exclude animal products can be deficient in vitamin B12 and low in iron and zinc. However, carefully planned vegetarian and vegan diets can provide adequate nutrients for optimum health (McEvoy, Temple, & Woodside, 2012). An expert group came to the following conclusion: “Well-planned vegetarian diets are appropriate for individuals during all stages of the life cycle, including pregnancy, lactation, infancy, childhood, and adolescence, and for athletes” (Craig & Mangels, 2009).

Based on the evidence as a whole, the ideal diet has a low content of meat, especially processed meat. If meat is desired, then chicken and turkey are preferable to red meat. As discussed earlier in the unit, fish is valuable in the diet as it is clearly associated with a reduced risk of heart disease. In summary, therefore, the ideal diet is a variation of a vegetarian diet so that it is low in red meat and processed meat but contains fish. This dietary pattern is essentially the same as the Mediterranean diet. Such a diet can be constructed around Canada’s Food Guide.

Weight-Loss Diets

A 2016 search on Amazon’s website for books on the subject of weight loss generated 107,000 hits. Of these, 15,400 were published during 2014. The front covers are adorned with promises such as “quick-and-easy weight loss,” “permanent weight loss,” “revolutionary,” and “supercharge your metabolism.” As medical science is managing to make only painfully slow progress in learning how to help people lose weight, it is obvious that the vast majority of these books add nothing new to the subject. At most, they merely recycle old ideas or invent new ones.

The weight-loss industry goes far beyond books. Magazines on sale at the supermarket checkout also offer a never-ending menu of quick-and-easy breakthrough miracle diets. In addition, there are several commercial companies such as Jenny Craig and Weight Watchers that bring personalized help to the customer.

The reason for the rapid growth of the weight-loss industry and its current size is obviously related to the huge epidemic of obesity that has imposed a heavy burden on much of the world. At the same time, medical science has failed to come up with any drugs, diets, or other therapies that offer real hope. The only effective treatment is bariatric surgery, but this is only suitable for severely obese persons. It was true 30 years ago, and it is just as true today: most people who try to lose weight fail, and most who do succeed regain it.

Here we look at one treatment that has become hugely popular over the last 40-plus years. In 1973, Robert Atkins, a physician, published Dr. Atkins’ Diet Revolution.

The diet restricts carbohydrates such as those high in sugar, breads, pasta, and starchy vegetables and emphasizes foods of animal origin that are higher in protein and fat. The supporters of this diet claim that foods high in carbohydrates increase insulin levels and thus convert food into body fat. Atkins argued that people having carbohydrate meals eat more and become hungrier sooner. Atkins and his colleagues claim that people on his diet experience improved blood pressure and lower cholesterol.

Diets that are very low in carbohydrate are characterized by initial rapid weight loss due to excessive water loss. In the first few days, the body breaks down all available glycogen and protein stores for energy. For each gram of glycogen or protein breakdown, the body releases three grams of water from inside the cells, and this leads to dehydration. The body must then rely almost entirely on its fat stores for energy. However, fat is oxidized to a by-product called ketones to provide fuel.

High blood levels of ketones is a condition known as ketosis. There is a high acid load from the ketones on the kidneys; this causes the kidney to excrete an excessive amount of sodium, potassium, and water. Dieters are delighted by the rapid initial weight loss, so this diet can be appealing. Complications associated with low-carbohydrate, high-protein, high-fat diets include ketosis, dehydration, electrolyte loss, calcium depletion, weakness (due to inadequate dietary carbohydrates), and nausea (due to ketosis). The lack of fibre leads to constipation.

The diet has for many years been widely criticized in medical and nutritional circles, mainly on two grounds: first, that the increased intake of saturated fat would raise the blood cholesterol level and increase the risk of heart disease. However, detailed studies have revealed, to the surprise of many, that this does not happen. The other criticism is that the diet does not achieve useful weight loss: the rapid weight loss seen in the first few days will be reversed as soon as carbohydrates are reintroduced and the body rehydrates.

The Atkins diet has not really been properly tested in long-term studies. What has been done, however, is the next best thing. Carefully conducted trials have been conducted of diets with widely varying amounts of carbohydrates (though not at a level so low that subjects develop ketosis). In all such trials, subjects are instructed to reduce their energy intake.

Several trials have been carried out to investigate which diet produces the best results (low-carbohydrate, low-fat, high-protein). A diet low in carbohydrates (and low in energy) does appear to bring some modest weight loss during the first six months, but over a longer time period, one or two years, it fares no better than other diets.

One especially informative study is the following: Overweight subjects were fed diets with widely varying amounts of fat (20% versus 40%), protein (15% versus 25%), or carbohydrate (35% versus 65%) (Sacks et al., 2009). Most previous studies stopped after six months or a year, but this one continued for 2 years. The investigators saw no evidence that varying the amounts of macronutrients had any meaningful effect on weight loss. But what they did observe was that persons who attended the most sessions were the ones who achieved the most weight loss. While the average subject lost four kilograms after two years, those who attended at least two-thirds of the sessions lost nine kilograms.

The investigators interpret this as meaning that the most successful subjects were the ones who were well motivated to lose weight (as indicated by turning up for most sessions). In other words, while weight loss efforts generally have a poor rate of success, many people do achieve long-term success. This study gives us three lessons:

1. In the long term (one or two years), a low-carbohydrate, high-protein, high-fat diet is no more effective than diets with much larger amounts of carbohydrate and much less protein and fat. Such trials are not a true test of the Atkins diet, as the quantity of carbohydrate was far above the level that brings about ketosis. Nevertheless, we can state that these trials indicate that a low-carbohydrate diet has little value for weight loss over the long term.
2. Despite the fact that the subjects in this study were provided with intense counselling by well-trained professionals, the average participant lost only four kilograms in two years. This underlines how tough it is for most people to lose weight and how false are the promises of quick-and-easy weight loss.
3. Nevertheless, significant weight loss is possible. The key determinant appears to be motivation. Like running a marathon, if you want it badly enough, the goal can be achieved.

Books and TV Shows That Are Best Ignored

Books on weight loss are only one part of the large industry that churns out thousands of new books every year on health-related topics. If authors carefully checked their facts and only published information that was new and of proven value, then the number of new books published each year would be no more than a few dozen—perhaps a couple of hundred. The reality, alas, is altogether different. As noted earlier, a search on Amazon’s website for books on the subject of health that were published in the year 2014 generated almost 70,000 hits. In a great many cases, the authors have fertile imaginations and show little hesitation in inventing new “discoveries.” Such books have zero value. Moreover, they can be dangerously misleading, as most potential readers are not able to see through the distortions of biomedical science.

An excellent example of books of this type is on the (supposed) relationship between blood group, diet, and health. In 1997 Peter D’Adamo, a naturopath, published a book titled Eat Right for Your Type. He and his co-author argued that a person’s blood group determines the type of food one needs and that eating the wrong foods can contribute to certain diseases. This concept resembles other super-simple theories, such as detoxification and antioxidants, in that the complex biochemical and physiological processes that lead to diseases are reduced to a single sentence that anyone can understand.

Nevertheless, despite its total lack of credible supporting evidence, the book became a best seller. D’Adamo then cashed in on this success with a series of books that extended his concept to the treatment of a range of conditions, including cancer, cardiovascular disease, arthritis, allergies, and diabetes. Other books focused on longevity, weight loss, and menopause. One book has the title Eat Right for Your Baby: The Individualized Guide to Fertility and Maximum Health During Pregnancy. Blood groups, apparently, control all aspects of our bodies, much like yin and yang.

These books, and thousands of others of the same general type, illustrate the dangers of unscientific CAM therapies, namely that they distract from therapies that may be effective. For example, a person with heart disease who puts his faith in a book with the title Cardiovascular Disease: Fight It with the Blood Type Diet may decide that the dietary recommendations in that book make more sense than using such proven treatments as the consumption of more fish and a reduced intake of salt and sugar. The same problem applies equally to many other unproven CAM therapies, such as some of the dietary supplements described in this unit and some of the herbal products in the previous unit.

TV shows are another place where huge amounts of nutritional disinformation are disseminated. One well-documented example is Dr. Oz. He is a highly accomplished heart surgeon whose TV show is watched by millions of people across North America. His program covers various areas of health in addition to nutrition. Researchers from the University of Alberta made a careful analysis of the accuracy of his recommendations and claims (Korownyk, Kolber, McCormack, Lam, et al., 2014). Their findings revealed that at least half of his recommendations lacked supporting scientific evidence.

Summary

Health professionals speak with one voice in arguing that good nutrition is essential for health and well-being. There are a number of dietary supplements for which there is reasonably good supporting evidence. However, many CAM practitioners promote scientifically unproven ways to prevent or treat various diseases and to achieve a state of optimal health. Practices advocated may include megadoses of vitamins, other assorted nutritional supplements, fasting, and special diets. Supplements are sold in health food stores and are often advertised in newspapers. Indeed, a large industry has developed in recent years based on the marketing of supplements, many of questionable value. The health of consumers may be at risk from some of the nutritional practices being advocated and from some supplements.

Learning Activity

Self-test Quiz

Do the self-test quiz for Unit 11 as many times as you wish to check your recall of the unit’s main points. You will get a slightly different version of the quiz each time you try it. (This quiz does not count toward your final grade).

If you have trouble understanding the material, please contact your Academic Expert.

References