Many Americans start their day with a multivitamin and other dietary supplements, thinking that it’s an easy way to maintain good health.
But do vitamins actually produce the desired results?
The body needs 13 vitamins to function properly: vitamins A, C, D, E, K and the B vitamins, which include thiamine, riboflavin, niacin, pantothenic acid, biotin, vitamin B-6, vitamin B-12 and folate.
While many people assume that a vitamin is necessary to get the recommended amount of all of those, doctors say that is often not the case.
“Mainstream medical advice is that supplementation is not necessary for most adults who eat a balanced diet,” said John Revis, MD, an internist at NorthShore University HealthSystem.
The U.S. Food and Drug Administration (FDA) does regulate vitamins, but “they are regulated differently than drugs, and the agency does not sign off on efficacy. Our charge primarily deals with safety,” says Dr. Daniel Fabricant, Director of the FDA’s Division of Dietary Supplements.
Dr. Fabricant recommends that individuals have a good reason why they are taking a vitamin or supplement. He also warns, “If claims sound too good, they probably are.”
Similarly, in November 2013 the U.S. Preventive Services Task Force issued draft guidelines stating that there is no conclusive evidence that supports taking certain vitamins and minerals alone, together or in a multivitamin for the prevention of heart disease or cancer. The Task Force also noted, though, that there was insufficient data to support a recommendation against taking most of these supplements.
“This study does not change the fact that there are many established benefits of vitamins and supplements. My opinion is that this is a call for more research,” says Duffy MacKay, practicing naturopath and Vice President of Scientific and Regulatory Affairs at the Council for Responsible Nutrition.
“Multivitamins can fill nutrient gaps, and as many people are not even reaching the recommended dietary allowances for many nutrients, that’s reason enough to add an affordable and convenient multivitamin to their diets,” MacKay says.
Failure to consume enough of a certain vitamin can lead to a deficiency disease, such as rickets caused by a lack of vitamin D; however, such conditions are uncommon.
“We don’t see too many deficiencies,” Dr. Revis says.
Dr. Jennifer Friedman of Northwestern Memorial Physicians Group in Deerfield says that while she typically recommends that women of childbearing age take folic acid, her overall recommendation on vitamins depends on the individual patient.
“I take numerous factors into account, including family history, how they are feeling, any symptoms they may be experiencing, medications and how they tolerate vitamins,” Dr. Friedman says.
Individuals taking supplements should tell their doctor. “It is useful to know what specific vitamins and how much someone is taking,” Dr. Revis says. “Most of the time it’s fine, but occasionally we’ll pick up an interaction that might be clinically important.”
“Vitamins are one component of a healthy lifestyle when used in combination with a healthy diet and exercise,” MacKay says. “People need to manage their expectations. There is no magic bullet.”