Complementary Health Approaches

Natural Products

Most complementary health approaches fall into one of two categories: natural products or mind and body practices. This section addresses natural products.

What Are Natural Products?

Natural products used in complementary health include herbs, vitamins, minerals, probiotics, and a variety of other substances such a glucosamine and fish oil. Natural products are widely marketed and often sold as dietary supplements.

Not all uses of dietary supplements are considered to be complementary. For example, the use of folic acid supplements before pregnancy and during early pregnancy to reduce the risk of neural tube birth defects is part of conventional medicine.

Research has been done on a variety of dietary supplements, but in many instances there isn’t enough scientific evidence to show whether they are effective and safe. More needs to be learned about the effects of these products in the human body.

You can find dietary supplements in supermarkets, pharmacies, and other stores. They are often shelved in the same area as over-the-counter drugs, but there are important differences between the two kinds of products. Although the U.S. Food and Drug Administration (FDA) regulates both dietary supplements and drugs, the regulations for dietary supplements are less strict.

There have been problems with contamination of some dietary supplements. In particular, some products marketed for sexual enhancement, weight loss, or bodybuilding have been found to contain potentially harmful ingredients not listed on the label. Some products marketed for arthritis or pain have also been found to contain illegal hidden ingredients. Another concern about supplements is that some can interact with drugs.

Use of Natural Products in the United States

According to the 2012 National Health Interview Survey, 17.7 percent of American adults had used a natural product other than a vitamin or mineral supplement in the past year. The most commonly used product was fish oil/omega-3s (reported by 7.8 percent of all adults). Other popular products included glucosamine/chondroitin, probiotics or prebiotics, melatonin, and coenzyme Q10.

For More Information

You can find more information about dietary supplements on the Web site of the National Center for Complementary and Integrative Health (NCCIH) at and on the Web site of the Office of Dietary Supplements of the National Institutes of Health at

You can learn about drug-supplement interactions through this educational module on NCCIH’s Web site.

See NCCIH's A to Z list of health topics to find information about the research on a specific dietary supplement or medical condition.