Dietary Supplements 101

dietary supplements

Although most people get all of the vitamins, minerals, and nutrition that they need from their daily diet, it is very common for individuals to take over the counter dietary or herbal supplements for a variety of reasons.

How to Use Supplements Safely

  • Dietary supplements and multivitamins are not necessarily the same thing! We define a dietary supplement as a product taken orally that contains one or more ingredients, such as vitamins or amino acids. They supplement one’s diet and we do not consider them food. A multivitamin is a combination of vitamins and minerals that people should ideally be getting from their foods or environment. Sometimes, multivitamins are made for a specific population (such as prenatal vitamins for pregnant women).
  • Dietary supplements do not treat, diagnose, or cure diseases.There is insufficient evidence to prove that multivitamins or over the counter supplements prevent cardiovascular disease or cancer in the general population. There are exceptions to this, such as using folic acid during pregnancy to reduce the risk of birth defects or taking iron supplements for iron-deficiency anemia.
  • Using supplements improperly can be harmful. It can be dangerous to take more than the directed amount of a supplement. Taking combinations of supplements or substituting them in place of prescribed medicines can be harmful and have life-threatening impact.
  • Some supplements can have unwanted effects before, during, or after surgery. It is important to speak with a healthcare professional about supplements before undergoing any type of procedure.

Speak with a HealthCare Professional

If you choose to take herbal supplements, it is important that you always let your doctor know what supplements, and how much you are taking daily.

Supplements and herbs can interact with other medications, which is why it is important to always check with your doctor that it is safe for you.  One common example is St. John’s Wort, which interacts with multiple drugs, including oral contraceptives, coumadin, benzodiazepines and more.

Be an Informed Consumer

Supplements do not need to be proven safe by the FDA before being marketed to the public, which means it is important for consumers to be mindful of what they are taking.

Know your supplements!Not all dietary supplements are made equal, and it is important to know whatyou are putting into your body. Here are a few resources to help you learn more about what ingredients make up your herbal or dietary supplement.

The Bottom Line

Millions of Americans safely consume multivitamins and dietary supplements and experience no poor side effects. It is important to check in with a healthcare provider to make sure the supplements you are taking are safe for you.

If you do experience an adverse effect after taking a supplement, we recommend reporting the medication to the FDA and the drug manufacturer as soon as possible.For information on how to do this, go to


Julie Marsala, MD, is a family medicine resident at the University of Vermont Medical Center. 

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