Overview

A vitamin and mineral supplement provides a variety of nutrients that are also found in food. These supplements are often called multivitamins. They come in the form of pills, chewable tablets, powders, and liquids.

A standard multivitamin may contain:

• Water-soluble vitamins. These include vitamin C and the B vitamins, such as thiamine, niacin, biotin, folic acid, and B12.
• Fat-soluble vitamins. These include vitamins A, D, E, and K.
• Minerals. These include calcium, copper, iron, and zinc.
• Other ingredients that aren't vitamins or minerals. Examples include lutein and lycopene. These are antioxidants.

The best way to get the vitamins and minerals you need is by eating a wide variety of healthy foods. A supplement can't make up for unhealthy eating habits. But some people may find it hard to get all the nutrients they need from food. This includes people who have food allergies and women who are pregnant or breastfeeding. A supplement can help fill in the gaps.

What to look for in a supplement

• Choose one that provides a variety of vitamins and minerals (a multivitamin) rather than a supplement that provides only a single vitamin or mineral (unless your doctor has recommended that you take an individual vitamin or mineral).
• Pick one that, along with the foods you eat, provides the Recommended Dietary Allowance (RDA) for each vitamin and mineral. Supplements that provide a lot more than the RDA can cause health problems. This is especially important for minerals and the fat-soluble vitamins A, D, E, and K. These are stored more easily in the body, and they can build up to dangerous levels.
• Check the expiration date. Do not buy supplements that have expired or that will expire before you can finish the bottle.
• If the supplement has the United States Pharmacopeia (USP) seal, the supplement has been tested and contains the amounts of vitamins and minerals that are listed on the label.
• Check the label for other ingredients. Some supplements may contain food ingredients, such as wheat, corn, eggs, or gelatin. If you have a food allergy or are sensitive to these foods, look for supplements that don't have those ingredients.

Other things to know about supplements

• The U.S. Food and Drug Administration (FDA) does not regulate dietary supplements in the same way that it regulates medicines. This means that supplements can be sold without research on how well, or even if, they work.
• No supplement has been proved to cure diseases such as cancer, diabetes, heart disease, or digestive problems. If it sounds too good to be true, it probably is. Be cautious of supplements that promise quick or dramatic results.
• A generic brand (or store brand) often works just as well as a name brand supplement. Look for generic brands that contain the same amount of vitamins and minerals as the name brand.
• Most man-made (synthetic) vitamins are as good as natural vitamins.