Vitamin and Mineral Supplements: Which Patients Will Benefit?

JoAnn E. Manson, MD, DrPH


February 05, 2018

Hello. I am Dr JoAnn Manson, professor of medicine at Harvard Medical School and Brigham and Women's Hospital in Boston, Massachusetts. I'd like to talk with you today about vitamin and mineral supplements. Is there a rational approach? Most of our patients are taking dietary supplements, usually vitamin or mineral supplements, and we are often asked questions such as, "Should I take dietary supplements? If so, what supplements should I take? What dose(s)? If I'm taking certain medications, should I avoid specific supplements or go out of my way to take certain supplements?" Clinicians receive surprisingly little formal training in this area.

My colleague and I thought it would be helpful to distill the available information from professional societies and other sources in a brief JAMA viewpoint article,[1] with a very succinct table that is quite user-friendly, in order to provide guidance on this topic.

We start with the premise that vitamins and minerals are best obtained through a healthy and well-balanced diet. That's where the nutrients are best absorbed and are safest, and the optimal ratio of nutrients can be obtained. However, some segments of the population—some subgroups—may benefit from targeted treatments. Although routine supplementation is not recommended for the generally healthy population, targeted subgroups may benefit from these supplements.

We suggest a framework for thinking about this in terms of life stages and high-risk subgroups who have certain types of medical conditions or who are taking certain medications. In terms of life stages, we talk about pregnancy, where folic acid is very important for preventing neural tube defects; and the American Academy of Pediatrics has specific guidelines for vitamin D and iron supplementation in breastfed infants. In middle and older adulthood, there are guidelines for B12, calcium, and vitamin D.

In terms of specific conditions and specific high-risk subgroups, we talk about pernicious anemia and the specific amount of B12 supplementation that is needed, and also groups who have malabsorption syndromes, such as Crohn's disease or celiac disease, and post–gastric bypass surgery, when patients may benefit from supplementation. Also in conditions such as osteoporosis or macular degeneration, specific supplements will be of value.

With certain medications, such as proton pump inhibitors (PPIs) and metformin, supplementation may be of benefit. This includes B12 supplementation for patients taking metformin and other supplements for those using PPIs.

Once a decision is made to use dietary supplements, it's important to use a product that has undergone quality-control testing. We recommend looking at the label for evidence of an independent quality-control audit. This ensures that the content is what is on the label, and that the product is pure (not contaminated with microbes, heavy metals, or toxins). Looking for the US Pharmacopeia seal (USP), the NSF International seal, the UL seal, or other evidence of an independent audit can be very helpful.

Also in the article we talk about certain websites that can be helpful to check for interactions between supplements, as well as interactions between supplements and medications. We also endorse checking out the National Institutes of Health Office of Dietary Supplements website, which has very helpful information about pros and cons of different supplements. We hope you find the article helpful and the information—especially in the succinct table—user-friendly and accessible. Thanks so much for your attention. This is JoAnn Manson.


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