Dietary supplements are consumed by humans for many reasons, including performance enhancement, weight loss, filling dietary gaps, treating maladies, or general health maintenance. A majority of North Americans consume dietary supplements at some point in their lives.
The vitamin and supplement industry is projected to be worth $306.8 billion globally in 2026.[1]One out of two people in North America report taking supplements regularly (most commonly a daily multivitamin).[2][3] What oversights exist to ensure we are getting what we pay for. Even if we are, do we really need it, or is it one of the best scams running?
Supplements by the numbers
In 2014, the dietary supplement industry in Canada was valued at $5.6 billion. From 2004 to 2014, it performed at an average annual growth rate of 4.2%.[4]Using this level of growth, the industry would be valued at around $7.8 billion for 2021.
Forty-five per cent of Canadians and 68% of Americans report daily use of dietary supplements.[5][6]Usage in European countries has a broad range from as low as about` 5% in Greece to more than 58% in Denmark. Women are more likely to use dietary supplements than men.[7]
In 2018, advertisers spent more than $900 million USD marketing vitamins, minerals, and other dietary supplements to Americans. Average yearly expenditure for individual consumers who take dietary supplements is $368 USD.[8]
What do you really need?
In the nutritional world, nutrients are broken into two main categories: macronutrients (carbohydrates, proteins, and fats) and micronutrients (vitamins and minerals). Water, technically the third category, might be less exciting but is obviously critical.[9] The idea behind a supplement is that there is a need for it or a dietary gap, but it is not meant to be a primary nutrient source. Rather, it plays a supporting, or, I guess we could say, supplemental role. It is there to fill a deficiency or to provide a beneficial boost. This begs the question – what do we actually need? Or, what are we lacking in our diet that necessitates supplementing?
Studies show that the average Canadian is deficient in vitamin D. There is also data indicating that many Canadians are also deficient in magnesium, vitamin A, and calcium.[10] What are the health implications of these deficiencies? Weak bones, weak immune system, slower healing from injuries, and metabolic issues that can contribute to unhealthy weight gain.[11]
Does taking vitamins mean we are more likely to be healthy? Research has been conducted on those who take supplements regularly, monitoring body mass index (BMI) and diets. One study shows that both smokers and those who assess themselves to be “very active” are less likely to take supplements. On the flip side, being female or Caucasian is correlated with a greater likelihood of consuming supplements.[12] These datasets show no correlation between positive general health and vitamin consumption. In fact, there is some information supporting an inverse relationship.
Do you get what you pay for?
There is a glaring lack of regulatory oversight surrounding the manufacturing and sales of dietary supplements in the United States. In theory, the U.S. Food and Drug Administration (FDA) is responsible for ensuring the safety, quality, and efficacy of the supplements being sold. In reality, it appears to be the Wild West, and as long as a company does not ruffle feathers and avoids inspiring someone to file a formal product complaint, almost anything goes. Under current U.S. law, “supplements” are presumed safe. This means that they do not need to pass any rigorous tests before they go to market – or any tests at all, actually.[13] Supplement manufacturers circumvent this seemingly obvious checkpoint because they are not classified as “drugs” (i.e. they are “not intended to treat, diagnose, prevent, or cure diseases”).[14]In fact, the only time the FDA gets involved is if the packaging and marketing misrepresent the product’s intentions or efficacy, or if the product itself is found to have been adulterated … after a claim has been investigated and proven by the FDA. Only then can the FDA remove it from the market.[15]
In Canada, on the other hand, “natural health products” must be assessed by Health Canada and found to be safe, effective and of high quality, under their recommended conditions of use before they can be sold legally. Both safety and efficacy evidence must be provided by the manufacturer to Health Canada, and must meet all standardized requirements prior to approval for retail.[16]
Assuming that what we believe we are buying is in the container, how do our bodies react to those supplements, versus obtaining nutrients via regular food? One important point is that the longer a supplement such as a multivitamin sits on the shelf, the more its quality is diminished and the lower the international units (IU) or milligrams (mg) of nutrition the consumer receives. (IU and mg are the metrics that vitamin/supplement companies use most often to express quantity/dosage.) To combat this, manufacturers are known to create products with more IUs/mgs than stated on packaging, with the assumption that quality will deteriorate through the shipping, stocking, and sales processes.[17]
Once someone has identified gaps in diet or dietary needs, another consideration is the quality of the supplement in relation to the body’s ability to absorb nutrients contained within, commonly referred to as “bioavailability.”[18] There are many factors that go into the bioavailability of foods and dietary supplements: host factors such as fed or fasted state of the individual, health and function of the digestive tract, presence of illness, presence of other vitamins at time of consumption and in what quantity (known as physicochemical dietary scaffolding). For example, absorption of iron is more efficient in the presence of vitamin C. Other important factors include nutrient load, (i.e. what dosage you are getting; a lower load is often correlated with greater absorption), and environmental factors such as sun exposure and extreme temperature exposure.[19]
Increasing the value of our urine
If our bodies are not in an optimal state to receive supplements, what happens to those micronutrients that are not absorbed immediately? You can probably guess, but it is worth stating that excess water-soluble vitamins are excreted from the body through urine and in relation to the dosage in which excess is consumed.[20] Essentially, if we already have a balanced diet and consume a significant amount of additional vitamins, we are literally pissing away our investment.
Do dietary supplements lead to better health?
The billion-dollar question – do supplements do what the buyer believes they are going to do? It comes down to a matter of beliefs and results. Studies show that people who take dietary supplements on a regular basis believe that those supplements make them more healthy, allow for better focus, and enhance performance. [21]That said, there is a body of research indicating that, in mostly healthy individuals, dietary supplements have no positive impact. Meeting dietary needs of macro and micronutrients is important for health maintenance and increased avoidance of chronic diseases, but research suggests this is only the case if those needs are met through regular food.[22]
A balanced diet, rich in a variety of vegetables and fruits, low in trans fats, sugars, and heavily processed foods, and modest in meat consumption, should provide us with all the nutrients we need to lead a healthy lifestyle.[23] However, for various reasons, some of us need to supplement our diet. In most of those cases, a multivitamin a day can offer the support we are seeking at a cost that we and our bodies can stomach. [24]
[1] https://www.pharmiweb.com/press-release/2020-08-06/growing-at-a-cagr-of-90-global-dietary-supplements-market-size-share-will-reach-usd-3068-billi
[2] https://www150.statcan.gc.ca/n1/pub/82-625-x/2017001/article/14831-eng.htm
[3]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5540241/
[4] https://www.chpcanada.ca/sites/default/files/healthy_growth_final_report.pdf
[5] https://www150.statcan.gc.ca/n1/pub/82-625-x/2017001/article/14831-eng.htm
[6] https://www.persistencemarketresearch.com/market-research/dietary-supplements-market.asp
[7] https://www.nature.com/articles/ejcn200983
[8] https://www.nccih.nih.gov/research/research-results/americans-spend-30-billion-a-year-outofpocket-on-complementary-health-approaches
[9] http://www.injirr.com/article/view/8/5
[10] https://www.canada.ca/en/health-canada/services/food-nutrition/food-nutrition-surveillance/health-nutrition-surveys/canadian-community-health-survey-cchs/canadian-adults-meet-their-nutrient-requirements-through-food-intake-alone-health-canada-2012.html
[11] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6775441/
[12] https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185258
[13] https://www.researchgate.net/publication/271732644_The_Regulation_of_Dietary_Supplements_Within_the_United_States_Flawed_Attempts_at_Mending_a_Defective_Consumer_Safety_Mechanism
[14] https://www.fda.gov/food/dietary-supplements/dietary-supplement-products-ingredients
[15] https://www.fda.gov/food/dietary-supplements/dietary-supplement-products-ingredients
[16] https://www.canada.ca/en/health-canada/services/drugs-health-products/natural-non-prescription/regulation.html
[17] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5267296/
[18] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/bioavailability
[19] https://journals.sagepub.com/doi/full/10.1177/2397847317696366
[20] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4134006/
[21] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4134006/
[22] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5774790/
[23] https://www.bmj.com/content/369/bmj.m2511
[24] https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-13-72
