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Nutritional Supplementation (April 2022)

Written by Connor Freed, MS student in Animal and Nutritional Sciences

Hey Mountaineers! This is your fellow graduate assistant of Dining Services, Connor Freed, here. I hope everyone is enjoying this nice weather and staying on top of assignments as the semester winds down. I wanted to take some time to discuss a pet peeve of mine in the field of nutrition, and that is the misleading marketing tricks used to sell unneeded or unproven products and supplements. As a future-dietitian, I often get asked about what supplements are effective at this or that, and after learning more about the current state of the supplement industry, I feel that this is an important subject to shed some light on. This post will focus mainly on micronutrient supplementation, but the same principles will apply to athletic, herbal and all other forms of supplements.

Regulation of Supplements

It is estimated that half of all Americans take a health supplement each day 1. Many of us see the quality of labels and packaging and assume that a product has met certain standards, but just as you should never judge a book by its cover, you should never take what's on a supplement’s label as fact. Here’s why! The FDA does not review supplements before they are on the market, and it is up to the manufacturer to prove the safety and efficacy of their product, of which they are under no obligation to show to consumers 1. The FDA is lacking an effective system to detect harm from many supplements, but instead takes action only once someone has been seriously injured and reports this injury 1. On top of that, companies use vague and unsubstantiated claims for their products such as, “boosts your immune system” and “supports bone health”, which mean almost nothing in a scientific sense (crazy right?!). Keep in mind that we are talking about an estimated 85,000 supplements on the market at any given time and this number is only expected to increase 1. With all those products, you may think that we have an extensive process to make sure these supplements are safe and effective.

Let’s talk about the term “all natural” seen on many supplement containers. Many people think that if something is labeled “all natural” it must be safe. This is just a marketing trick, as there are countless “all-natural” harmful pathogens and toxic substances that can injure you and countless body systems if consumed. But even if everything that was labeled “all natural” was safe, what if the information on the label and the actual contents of the bottle were completely different? For things like herbal products, you would expect labels to tell you exactly what you are consuming, right? That’s not always the case. Let’s take a closer look.

Researchers from Guelph University aimed to test the contents of various herbal products through DNA barcoding, where 44 herbal products from 12 different companies were tested 2. 59% of the products contained DNA from different plant species than were listed on the label, and one-third contained contaminants or fillers not listed on the label 2. Only two out of the 12 companies (17%) had accurate label information and uncontaminated products. A similar study was conducted at Stony Brook University to test the DNA contents of 36 different Black Cohosh dietary supplements 3. The researchers found that 25% of the products contained DNA from plants that were related to but different from Black Cohosh 3. Inaccurate labeling is extremely problematic for those with allergies or other conditions where mislabeled products can interfere with health.

Are Supplements Beneficial?

Even if we assume that supplements are accurately labeled, the jury is still out on whether they are actually effective in preventing disease or mortality. A 2013 review investigated the benefits of vitamin and mineral supplementation on cardiovascular disease, cancer and all-cause mortality, and found no clear evidence of a positive effect in healthy individuals without nutrient deficiencies 4. A double blind, randomized, placebo-controlled study was conducted to examine the effects of multivitamin supplementation vs. placebo on cognitive decline in 5,947 elderly adult males 5. The results showed that after a 12-year follow-up, no difference in mean cognitive decline between groups, and the study concluded that the multivitamin did not provide cognitive benefits 5. Some studies have even shown harm when supplementing with vitamins and minerals. A 2013 review examined the effects of antioxidant supplementation (vitamin A, vitamin E, vitamin C, selenium, and beta carotene) on all-cause mortality, and found that supplementation did not result in lower mortality 6. In fact, some of the trials showed a higher mortality rate in the supplementation groups compared to placebo 6. Now, this does not mean that these nutrients themselves were harmful or “unhealthy,” but rather there may be an issue with the amount being consumed.

If you have ever spent time with a dietitian (RDN), you will hear the word “moderation” being used frequently. Optimal health and nutrition is a delicate balance of many factors, and consuming too little or too much of a nutrient can tip that balance. If we made a graph to show the risk of adverse health effects (y-axis) over the amount of a specific nutrient consumed (x-axis) you will most likely get a ‘U-shaped” curve. That is, risks for adverse health effects increase if we are undernourished or overnourished (so to speak). Getting too much of one nutrient can be just as detrimental to health as getting too little. Here is a little visual to illustrate what I mean.
Note: Graph is not to scale

Risks for adverse health effects increase if we are undernourished or overnourished (visualized by a U shaped curve)

The tolerable Upper Intake Level (UL) is the maximum daily intake of a certain nutrient that is unlikely to cause harmful health effects 7. Consuming a nutrient in amounts higher than the UL has the potential to cause serious problems, especially if done on a consistent basis. One big problem I see with supplement companies is the dosages they use for their products, as many supplements will contain the nutrient in amounts at or very close to the UL. People who are taking these supplements everyday could put themselves at risk for toxicities to develop over time. For example, someone who takes a vitamin A supplement with a dosage at the UL, and also eats a nutrient dense diet, is consuming well over the amount recommended and more than likely getting a toxic dose which can lead to serious adverse health effects.

I think many people don’t consider risks in vitamins and mineral toxicities since they are seen as “all-natural” or “organic”. But if we really step back and look at it, is there really anything “natural” about supplements? Vitamin C supplements are commonly dosed at around 1000 mg. To get that amount from food, you’d have to eat around 8 entire cantaloupes or 15 oranges (not super realistic right?) 1. Vitamin E supplements are commonly dosed at 1000 International Units (IU). To obtain that much from food, you would have to eat around 1,670 almonds (I like almonds, but come on!) 1. My point here is that just because a substance is found in nature, it does not mean it is safe to indiscriminately consume highly concentrated amounts.

Supplement Usage

This is not to say that there is no use for supplements, as they can be very beneficial for those with deficiencies or those who aren’t able to consume an adequate diet or get enough of what they need (examples may include athletes, individuals following surgery, during times of illness, during pregnancy, breastfeeding individuals, older adults, and more). When vitamin and mineral requirements are not being met through the diet alone is when a micronutrient supplement should be considered 8. However, it is the position of the Academy of Nutrition and Dietetics that, “routine and indiscriminate use of micronutrient supplements for the prevention of chronic disease is not recommended, given the lack of available scientific evidence 8”. The big takeaway message here is food first! Try to get your vitamin and mineral needs met through the meals and snacks you consume. When you eat an orange, you’re not just getting vitamin C, but also fiber, vitamin A, calcium, iron, and many more nutrients. You’re also getting these nutrients in a dose that, evolutionarily speaking, our body is equipped to handle.

Nevertheless, for those who may require a micronutrient supplement, please first speak with your PCP or RDN and try to find a reputable brand that does third-party testing of their products. Look for labels that indicate third-party verification (NSF for example). This means that the product has been sampled and tested from an outside source to verify its contents. And lastly, be mindful of the dose you are consuming from the supplement, as you will more than likely get that nutrient through your diet as well. Stay away from supplements with doses at or near the UL, and only take the amount recommended by the USDA’s Dietary Guidelines for Americans.

Until next time!


  1. “Supplements and Safety.” PBS, Public Broadcasting Service, 19 Jan. 2016, Accessed 8 Apr. 2022.
  2. Newmaster, S. G., Grguric, M., Shanmughanandhan, D., Ramalingam, S., & Ragupathy, S. (2013). DNA barcoding detects contamination and substitution in North American Herbal Products. BMC Medicine, 11(1).
  3. Baker, D. A., Stevenson, D. W., & LittLe, D. P. (2012). DNA barcode identification of black cohosh herbal dietary supplements. Journal of AOAC INTERNATIONAL, 95(4), 1023–1034.
  4. Fortmann, S. P., Burda, B. U., Senger, C. A., Lin, J. S., & Whitlock, E. P. (2013). Vitamin and mineral supplements in the primary prevention of cardiovascular disease and cancer: An updated systematic evidence review for the U.S. Preventive Services Task Force. Annals of Internal Medicine, 159(12), 824–834.
  5. Grodstein, F., O’Brien, J., Kang, J. H., Dushkes, R., Cook, N. R., Okereke, O., Manson, J. A. E., Glynn, R. J., Buring, J. E., Gaziano, J. M., & Sesso, H. D. (2013). Long-term multivitamin supplementation and cognitive function in men. Annals of Internal Medicine, 159(12), 806–814.
  6. Bjelakovic, G., Nikolova, D., & Gluud, C. (2013). Antioxidant supplements to prevent mortality. JAMA, 310(11), 1178.
  7. U.S. Department of Health and Human Services. (n.d.). Office of dietary supplements - nutrient recommendations: Dietary reference intakes (DRI) . NIH Office of Dietary Supplements. Retrieved April 12, 2022, from
  8. Marra, M. V., & Bailey, R. L. (2018). Position of the Academy of Nutrition and Dietetics: Micronutrient Supplementation. Journal of the Academy of Nutrition and Dietetics, 118(11), 2162–2173.