Are Vegetables Enough?

Vitamins are organic food substances or nutrients critical for metabolism, growth, and overall health. Our body does not produce vitamins; we must get them from food.

A well balanced diet with plenty of whole grains, fruits, and vegetables, and a healthy lifestyle (physical activity, no smoking, moderate alcohol consumption), should provide all the vitamins we need, and in the right amounts.

However, as Mark Hyman, MD, explains, many of us are nutritionally depleted. Humans used to subsist on wild foods, which contained dramatically higher levels of vitamins, minerals, and essential fats. Today, because of depleted soil, industrial farming, and hybridization techniques, we produce food with fewer nutrients. Furthermore, we frequently consume processed, factory-made foods, which have no nutrients, and increasingly bear the burden of environmental toxins, lack of sunlight, and chronic stress, all of which lead to higher nutritional needs.

Subsequently, some people turn to vitamin supplements to fill in the gaps. Supplements may help some people obtain adequate amounts of essential nutrients. But more of a good thing is not necessarily better—and can even be dangerous. In a position paper on dietary supplements, the Academy of Nutrition and Dietetics expressed concern that consumers are not well informed about the safety and effectiveness of dietary supplements, and have difficulty interpreting labels on products, which can expose them to health risks.

The U.S. Department of Agriculture's 2005 Dietary Guidelines for Americans states, "Supplements may be useful when they fill a specific identified nutrient gap that cannot or is not otherwise being met by the individual's intake of food. Nutrient supplements cannot replace a healthful diet. Individuals who are already consuming the recommended amount of a nutrient in food will not achieve any additional health benefit if they also take the nutrient as a supplement. In fact, in some cases, supplements and fortified foods may cause intakes to exceed the safe levels of nutrients."

Certain groups may benefit from supplements, including those on a restrictive diet, older adults, vegetarians and vegans, pregnant women, or those with medical conditions that limit food choices. For the rest of us, a healthy diet will always be the best way to get the full range of vitamins.

If you choose to take supplements, refer to the Institute of Medicine's Dietary Reference Intakes for the best available, evidence-based standards for estimating optimal vitamin intake. Only purchase supplements made from whole foods with no additives, colors, fillers, or allergens. The best supplements use raw materials free from toxins such as mercury or lead, which are made in factories that follow Good Manufacturing Standards.

Allison Massey, RD reviewed this article.



National Center for Complementary and Alternative Medicine. "Using Dietary Supplements Wisely." Web. March 2010.

Academy of Nutrition and Dietetics. "Dietary Supplements." Web. January 2013.

"Position of the American Dietetic Association: Nutrient Supplementation." Journal of the American Dietetic Association 109 (2009): 2073-2085.

Mercola, Joseph, MD. "Can Vitamins Shorten Your Life?" Web. 6 May 2008.

Hyman, Mark, MD. "Savvy Supplement Shopping." Blog. Web. 18 January 2013.

Darrah, Lindsay. "Vitamins: The Who, What, Where, Why, and How's." Vanderbuilt University. Web.

Office of Dietary Supplements. National Institutes of Health. "Frequently Asked Questions." Web. 6 June 2011.

Institute of Medicine. "Dietary Reference Intakes Essential Guide Nutrient Requirements." Web. 7 February 2011.