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January 7, 2019

Vitamins and Nutritional Supplements: What Do I Need to Know?

JAMA Intern Med. 2019;179(3):460. doi:10.1001/jamainternmed.2018.5880

Vitamins and nutritional supplements include a very wide range of vitamins, minerals, and chemicals meant to add to the nutrients that people get through their diet.

What Are Vitamins and Supplements?

There are over 90 000 different supplements on the market. Some are derived from natural sources such as fish oil; however, many are created in a laboratory.

Do I Need to Take a Vitamin or Supplement?

For most people, the answer is no. Vitamins and supplements often advertise health benefits, such as improved thinking, better heart health, and a stronger immune system. For years, doctors have recommended certain supplements such as fish oil and multivitamins. However, these claims have not been supported by evidence from medical research.

Are Vitamins and Supplements Safe?

Most basic vitamins and minerals are presumed to be safe to take at the recommended doses. However, bad reactions to supplements are possible. An estimated 23 000 emergency department visits every year are directly related to taking nutritional supplements. These visits often result from toxic ingredients in some supplements such as heavy metals, steroids, and stimulants. Bad reactions can also happen owing to an overdose of a certain ingredient or because children accidentally take the supplement. Be honest with your physician about any supplements you are considering taking. Dispose of any old vitamins and supplements that are not being used.

Who Makes Sure That Vitamins and Supplements Are Effective and Safe?

The US Food and Drug Administration (FDA) oversees the vitamin and dietary supplement industry. In contrast to prescribed drugs, vitamins and supplements are assumed to be safe without any testing. The lack of requirement to show safety and effectiveness and the huge number of supplements on the market means that effective regulation is impossible.

Is a Balanced Diet Better Than a Supplement?

A balanced diet of fruits, vegetables, whole grains, some cheeses, fish, poultry, or lean meats provides all needed vitamins and nutrients. Evidence suggests that our body is better at absorbing nutrients from food than from supplements. Whole foods also provide the amounts and ratios of nutrients that our body can most efficiently use. Evidence shows that people who eat a balanced diet have positive health benefits, and these benefits are not found in supplements. Vitamins and supplements cannot make up for a less-than-healthy diet.

But I Am Vegetarian/Vegan/Gluten-Free/Paleo/etc. Do I Need a Supplement?

Most likely the answer is no. Vegetarian and other special diets generally provide adequate nutrients and vitamins without needing supplementation. Vegans are at increased risk for Vitamin B12 deficiency, but many vegan specialty foods, such as almond milk, are fortified with B12 to help ensure adequate daily intake. Sometimes a supplement may be recommended. Speak with your physician or a dietitian to discuss what makes the most sense for you.

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Article Information

Published Online: January 7, 2019. doi:10.1001/jamainternmed.2018.5880

Conflict of Interest Disclosures: None reported.

1 Comment for this article
James Larsen, M.Ed. | Military
The problem with saying a "healthy diet" will meet all nutritional needs is that it is an intervention that also requires research and proof.

a. The USDA says nutrients levels in food have declined significantly due to farming practices.

b. Suggesting someone can get enough vit D in their diet is actually extremely difficult (Holick, Heaney), if not either unaffordable or impossible.

c. The average American diet is now 60% processed food. See NIH Weight of the Nation.

d. There are other plant-based diet folks who are not vegetarians who are
at risk for a variety of nutrient deficiencies (Moran).

e. The AF documented that 25.4% of women and 8.9% of men arrived for Basic Training iron anemic (Cropper). All had passed a comprehensive physical. The Army's USARIEM lab has documented iron anemia as an issue for years (McClung).

f. Nutrient deficiency rates increase significantly in military basic training (Westphal) on a diet designed by professional dietitians.

g. Lappe documented 20% of women entering the Army with osteopenia/osteoporosis. Rivero documented very high rates of osteopenia in stress fractures in Navy training. These findings may also apply to an athletic population due to sweat losses and tissue damage (IOM, Kleges, Lappe).

h. Or look at Wagner's studies with vitamin D and pregnant and nursing women.

i. Therefore, the issue becomes how to cost-effectively identify the significant numbers of folks with deficiencies and treat them. At a minimum, folks with low trauma bone injuries should be evaluated and treated for likely underlying malnutrition (Brown).

j. Before anyone continues to assert that there is a nutritious healthy diet somewhere, they should look at the CDC NHANES data.