Skip to main content

Dietary Supplements

What Is a Dietary Supplement?Variety of dietary supplement pills

Dietary supplements are substances you might use to add nutrients to your diet or to lower your risk of health problems, like osteoporosis or arthritis. Dietary supplements come in the form of pills, capsules, powders, gel tabs, extracts, or liquids. They might contain vitamins, minerals, fiber, amino acids, herbs or other plants, or enzymes. Sometimes, the ingredients in dietary supplements are added to foods, including drinks. A doctor’s prescription is not needed to buy dietary supplements.

Should I Take a Dietary Supplement?

Do you need one? Maybe you do, but usually not. Ask yourself why you think you might want to take a dietary supplement. Are you concerned about getting enough nutrients? Is a friend, a neighbor, or someone on a commercial suggesting you take one? Some ads for dietary supplements in magazines or on TV seem to promise that these supplements will make you feel better, keep you from getting sick, or even help you live longer. Sometimes, there is little, if any, good scientific research supporting these claims. Dietary supplements may give you nutrients that might be missing from your daily diet. But eating a variety of healthy foods is the best way to get the nutrients you need. Supplements may cost a lot, could be harmful, or simply might not be helpful. Some supplements can change how medicines you may already be taking will work. You should talk to your doctor or a registered dietitian for advice.

What If I’m Over 50?

People over 50 may need more of some vitamins and minerals than younger adults do. Your doctor or a dietitian can tell you whether you need to change your diet or take vitamins or minerals to get enough of these:

  • Vitamin B12. Vitamin B12 helps keep your red blood cells and nerves healthy. Vitamin B12 is mainly found in fish, shellfish, meat, and dairy products. As people grow older, some have trouble absorbing vitamin B12 naturally found in food. They can choose foods, like fortified cereals, that have this vitamin added or use a B12 supplement.
  • Calcium. Calcium works with vitamin D to keep bones strong at all ages. Bone loss can lead to fractures in both older women and men. Calcium is found in milk and milk products (fat-free or low-fat is best), canned fish with soft bones, dark-green leafy vegetables like kale, and foods with calcium added like breakfast cereals.
  • Vitamin D. Some people’s bodies make enough vitamin D if they are in the sun for 10 to 15 minutes at least twice a week. But, if you are older, you may not be able to get enough vitamin D that way. Try adding vitamin D-fortified milk and milk products, vitamin D-fortified cereals, and fatty fish to your diet, and/or use a vitamin D supplement.
  • Vitamin B6. This vitamin is needed to form red blood cells. It is found in potatoes, bananas, chicken breasts, and fortified cereals.

What Are Antioxidants?

You might hear about antioxidants in the news. These are natural substances found in food that might help protect you from some diseases. Here are some common sources of antioxidants that you should be sure to include in your diet:

  • Beta-carotene—fruits and vegetables that are either dark green or dark orange
  • Selenium—seafood, liver, meat, and grains
  • Vitamin C—citrus fruits, peppers, tomatoes, and berries
  • Vitamin E—wheat germ, nuts, sesame seeds, and canola, olive, and peanut oils

Right now, research results suggest that large doses of supplements with antioxidants will not prevent chronic diseases such as heart disease or diabetes. In fact, some studies have shown that taking large doses of some antioxidants could be harmful. Again, it is best to check with your doctor before taking a dietary supplement.

What About Herbal Supplements?

Herbal supplements are dietary supplements that come from plants. A few that you may have heard of are gingko biloba, ginseng, echinacea, and black cohosh. Researchers are looking at using herbal supplements to prevent or treat some health problems. It’s too soon to know if herbal supplements are both safe and useful. But, studies of some have not shown benefits.

Are Dietary Supplements Safe?

Scientists are still working to answer this question. The U.S. Food and Drug Administration (FDA) checks prescription medicines, such as antibiotics or blood pressure medicines, to make sure they are safe and do what they promise. The same is true for over-the-counter drugs like pain and cold medicines.

But, the FDA does not consider dietary supplements to be medicines. The FDA does not watch over dietary supplements in the same way it does prescription medicines. The Federal Government does not regularly test what is in dietary supplements. So, just because you see a dietary supplement on a store shelf does not mean it is safe, that it does what the label says it will, or that it contains what the label says it contains.

If the FDA receives reports of possible problems with a supplement, it will issue warnings about products that are clearly unsafe. The FDA may also take these supplements off the market. The Federal Trade Commission looks into reports of ads that might misrepresent what dietary supplements do.

A few private groups, such as the U.S. Pharmacopeia (USP), NSF International, ConsumerLab.com, and the Natural Products Association (NPA), have their own “seals of approval” for dietary supplements. To get such a seal, products must be made by following good manufacturing procedures, must contain what is listed on the label, and must not have harmful levels of things that don’t belong there, like lead.

What’s Best for Me?

If you are thinking about using dietary supplements:

  • Learn. Find out as much as you can about any dietary supplement you might take. Talk to your doctor, your pharmacist, or a registered dietitian. A supplement that seemed to help your neighbor might not work for you. If you are reading fact sheets or checking websites, be aware of the source of the information. Could the writer or group profit from the sale of a particular supplement? Read more about choosing reliable health information websites.
  • Remember. Just because something is said to be “natural” doesn’t also mean it is either safe or good for you. It could have side effects. It might make a medicine your doctor prescribed for you either weaker or stronger.
  • Tell your doctor. He or she needs to know if you decide to go ahead and use a dietary supplement. Do not diagnose or treat your health condition without first checking with your doctor.
  • Buy wisely. Choose brands that your doctor, dietitian, or pharmacist says are trustworthy. Don’t buy dietary supplements with ingredients you don’t need. Don’t assume that more is better. It is possible to waste money on unneeded supplements.
  • Check the science. Make sure any claim made about a dietary supplement is based on scientific proof. The company making the dietary supplement should be able to send you information on the safety and/or effectiveness of the ingredients in a product, which you can then discuss with your doctor. Remember that if something sounds too good to be true, it probably is.

What Can I Do to Stay Healthy?

Here's what one active older person does:

Try following Pearl’s example—stick to a healthy diet, be physically active, keep your mind active, don’t smoke, see your doctor regularly, and, in most cases, only use dietary supplements suggested by your doctor or pharmacist.

Read about this topic in Spanish. Lea sobre este tema en español.

For More Information About Dietary Supplements

Department of Agriculture                                         
Food and Nutrition Information Center          
1-301-504-5414
FNIC@ars.usda.gov
www.nal.usda.gov/fnic

Federal Trade Commission
1-877-382-4357 (toll-free)
1-866-653-4261 (TTY/toll-free)
www.consumer.ftc.gov

Food and Drug Administration                               
Center for Food Safety and Applied Nutrition
1-888-723-3366
www.fda.gov/AboutFDA/CentersOffices/OfficeofFoods/CFSAN/default.htm

Medline Plus
National Library of Medicine      
www.medlineplus.gov

Office of Dietary Supplements                                    
National Institutes of Health
1-301-435-2920
ods@nih.gov
www.ods.od.nih.gov