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Home > Health Library > Dietary Supplements (Herbal Medicines and Natural Products)
In the United States, dietary supplements are substances you eat or drink. They can be vitamins, minerals, herbs or other plants, amino acids (the individual building blocks of protein), or parts of these substances. They can be in pill, capsule, tablet, or liquid form. They supplement (add to) the diet and should not be considered a substitute for food.
Dietary supplements are widely available in the United States in health food stores, grocery stores, pharmacies, on the Internet, and by mail. People commonly take them for health-related reasons. Common dietary supplements include vitamins and minerals (such as vitamin C or a multivitamin), botanicals (herbs and plant products, such as St. John's wort), and substances that come from a natural source (such as omega-3 fatty acids).
Makers of dietary supplements cannot legally say that dietary supplements can diagnose, cure, treat, or prevent disease. But they can say that they contribute to health maintenance and well-being.
People have used the active ingredients in dietary supplements for thousands of years to help health and to treat illness. Sometimes those supplements are the basis for some of today's common medicines. For example, people have used willow bark tea for centuries to relieve fever. Pharmaceutical companies eventually identified the chemical in willow bark that relieved fever and used that knowledge to produce aspirin.
The U.S. Food and Drug Administration (FDA) does not regulate dietary supplements in the same way that it regulates medicine. A dietary supplement can be sold without research on how well it works.
People use dietary supplements for many health conditions.
Researchers have found that some supplements do not help prevent or treat certain health problems. For example, beta-carotene and vitamin E do not lower risk of heart disease or heart attack.
Not all herbs and supplements are safe. If you are unsure about the safety of a supplement or herb, talk to your doctor, pharmacist, or dietitian.
Always tell your doctor if you are using a dietary supplement or if you are thinking about combining a dietary supplement with your conventional medical treatment. It may not be safe to forgo your conventional medical treatment and rely only on a dietary supplement. This is especially important for women who are pregnant or breastfeeding.
When using dietary supplements, keep in mind the following.
Other Works Consulted
Reichenbach S, et al. (2007). Meta-analysis: Chondroitin for osteoarthritis of the knee or hip. Annals of Internal Medicine, 146(8): 580–590.
Rozendaal RM, et al. (2008). Effect of glucosamine sulfate on hip osteoarthritis. Annals of Internal Medicine, 148(4): 268–277.
Sawitzke AD, et al. (2008). The effect of glucosamine and/or chondroitin on the progression of knee osteoarthritis. Arthritis and Rheumatism, 58(10): 3183–3191.
Thomson CA (2012). Food and nutrient delivery: Bioactive substances and integrative care. In LK Mahan et al., eds., Krause's Food and the Nutrition Care Process, 13th ed., pp. 291–305. St Louis, MO: Saunders.
U.S. Preventive Services Task Force (2014). Vitamin, mineral, and multivitamin supplements for the primary prevention of cardiovascular disease and cancer. U.S. Preventive Services Task Force. http://www.uspreventiveservicestaskforce.org/uspstf/uspsvita.htm. Accessed March 28, 2014.
Whitney E, Rolfes SR (2011). Vitamin and mineral supplements. In Understanding Nutrition, 12th ed., pp. 346–352. Belmont, CA: Wadsworth.
Current as ofJune 28, 2018
Author: Healthwise StaffMedical Review: Adam Husney, MD - Family Medicine
Current as of:
June 28, 2018
Medical Review:Adam Husney, MD - Family Medicine
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