The FDA does not have authority over dietary supplements in the same way it does prescription medicines. The Federal Government does not regularly test what is in dietary supplements, and companies are not required to share information on the safety of a dietary supplement with the FDA before they sell it. The companies are responsible for making sure the supplement is safe, but the FDA does not evaluate the safety of the product before the supplement is sold. 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.
Protein-containing supplements, either ready-to-drink or as powders to be mixed into water, are marketed as aids to people recovering from illness or injury, those hoping to thwart the sarcopenia of old age, to athletes who believe that strenuous physical activity increases protein requirements, to people hoping to lose weight while minimizing muscle loss, i.e., conducting a protein-sparing modified fast, and to people who want to increase muscle size for performance and appearance. Whey protein is a popular ingredient, but products may also incorporate casein, soy, pea, hemp or rice protein.
Fats contain both saturated and unsaturated (monounsaturated and polyunsaturated) fatty acids. Saturated fat raises blood cholesterol more than unsaturated fat, which may even help lower harmful cholesterol. Reducing saturated fat (most comes from meat, dairy and bakery products) to less than seven percent of total daily calories may help you reduce your cholesterol level. Whenever possible, replace saturated fat with monounsaturated and polyunsaturated fats.
Vitamins are either water-soluble or fat-soluble. Water-soluble vitamins dissolve in water and pass through the body quickly, meaning that the body needs them on a regular basis. Water-soluble vitamins include the B-complex vitamins and vitamin C. Fat-soluble vitamins are stored in the body's fatty tissue, meaning that they remain in the body longer. Fat-soluble vitamins include vitamins A, D, E, and K.
If you suspect that you have had a serious reaction from a dietary supplement, let your health care provider know. He or she may report your experience to the FDA. You may also submit a report to the FDA by calling 800-FDA-1088 or completing a form online. In addition, report your reaction to the dietary supplement company by using the contact information on the product label.