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Providing perspectives on recent research into vitamins and nutritionals


Five Ways to be Nutrition Agnostic and Healthier

By Michael McBurney

You have to like Steven Salzberg’s tagline “I cover pseudoscience and bad medicine, and sometimes good medicine”. He is the author of “The Top Five Vitamins You Should Not Take” published in Forbes.  As a reformed vitamin user, Steven recommends ditching the vitamins and eating more spinach and blueberries. Presumably, this is a metaphor for more vitamin (and mineral-rich) fruit and vegetable. 

Vitamins and minerals are not magic bullets. Nutrients are not drugs. Nutrients in the form of foods or dietary supplements do not prevent, mitigate or treat diseases. However, nutrients are essential for health. We need adequate nutrition for optimal health not pharmacologic doses. Let’s examine the 5 vitamins in question:

1.       Vitamin C. Inadequate vitamin C intakes do lead to scurvy. According to the most recent CDC report (NHANES 2003-2006), 1 of every 20 Americans (6%), are at risk of having scurvy (serum ascorbic acid levels < 11.µmol/L).  Plasma vitamin C levels vary seasonally. Paalanen and colleagues reported that plasma total vitamin C levels were 4-8 times higher in Russian subjects in fall than spring. Same can probably be said around the globe.

2.       Vitamin A and Beta-Carotene. Vitamin A and its dietary precursor, beta-carotene, are essential for vision. Preformed sources of vitamin A are found in animal products and dietary supplements, typically in the latter as retinyl acetate or retinyl palmitate. Taking large doses of preformed vitamin A can be harmful.  Higher intakes of beta-carotene from food sources may reduce the risk of cancer whereas the evidence isn’t as clear when using pharmacological doses of beta-carotene, especially in people who smoke. For more information on vitamin A, see Medline Plus.

3.       Vitamin E. It should be a more popular supplement because almost 100% of Americans are not consuming the recommended vitamin E intake from their diet. Vitamin E and prostate cancer has been in the news but rarely do headlines from one clinical study summarize the entire literature (See Mon, Oct 11, 2011 blog). Vitamin status (A, C, E and carotenoids) is adversely affected by socioeconomic status and adverse lifestyle indicators. It is wonderful that some people have the financial means and interest to adhere to MyPlate guidelines. However, for the majority who don’t, they should be encouraged to augment vitamin and mineral intakes with a supplement.

4.       Vitamin B6, or pyridoxine and related-compounds, was an odd mention. It is not clear why B6 was singled out. Usually, the focus is on B vitamins: B6, folic acid, and B12. They are all water-soluble and excess can be excreted in the urine. The risk of neuropathy is at chronic intakes of 2-6 grams vitamin B6 daily. These are not levels not readily found in dietary supplements unless it is a horse pill and multiple pills are taken daily.

5.       Multivitamins are a key contributor to nutrient intakes in America (Fulgoni et al, 2011). The evidence from the Iowa Women’s Health Study that dietary supplement use may increase mortality risk is questionable because 85% of the women were using dietary supplements. Where is the control group? Supplement users differ from non-users in dietary nutrient intakes, physical activity, BMI, and many other lifestyle indicators. Because  supplement use isn’t independent of other lifestyle behaviors, it may be possible to discern statistical relationships but causality cannot be ascribed to a single behavior, e.g. supplement use.

The truth of the matter is that most people are not eating the recommended number of servings of fruit and vegetables. Indeed, Murphy and associates analyzed food consumption data from NHANES 2003-2006. A single food accounted for 64% or more of the total intake of 5 nutrients found in fruit and vegetables. Poor dietary choices and inadequate intakes of vitamins C, A and E are not exclusive to Americans. The same issue prevails in Brazil.

Our goal should be to encourage adequate nutrition, by whatever  means – dietary choice and/or supplementation. Be a nutrition agnostic. Don’t judge people by the method they use to obtain nutrition. Judge them by measures of their nutritional status. And in guiding them to improve nutritional status, remember that nutrients are NOT drugs. Balance and moderation are the words for the day.


Murphy MM, Barraj LM, Herman D, Bi X, Cheatham R, Randolph RK. Phytonutrient intake by adults in the United States in relation to fruit and vegetable consumption. 2011 J Acad Nutr Diet doi:1016/j.jada.2011.08.044

Paalanen L, Prattala R, Alfthan G, Salminen I, Laatikainen T. Seasonal variation in plasma vitamin C concentration in Pitkaranta, Northwestern Russia. 2013 Eur J Clin Nutr doi:10.1038/ejcn.2012.185

Medeiros Pinheiro M, Ciconelli RM, Chaves GV, Aquino L, Juzwiak CR, Genaro P, Ferraz MB. Antioxidant intake among Brazilian adults – The Brazilian Osteoporosis Study (BRAZOS): a cross-sectional study. 2011 Nutr J doi:10.1186/1475-2891-10-39

Fulgoni II VL, Keast DR, Bailey RL, Dwyer J. Foods, fortificants, and supplements: Where do Americans get their nutrients? 2011 J Nutr doi:10.3945/jn.111.142257

Talwar D, McConnachie A, Welsh P, Upton M, O’Reilly D, Smith GD, Watt G, Saltar N. Which circulating antioxidant vitamins are confounded by socioeconomic deprivation? The MIDSPAN Family Study. 2010 PLoSOne doi:10.1371/journal.pone.0011312

Mursu J, Robien K, Harnack LJ, Park K, Jacobs DR. Dietary supplements and mortality rate in older women: The Iowa Women’s Health Study. 2011 JAMA doi:10.1001/archinternmed.2011.445