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How do I know whether a supplement's claims are true or false?

Supplement makers are not allowed to claim their product diagnoses, treats, cures, reduces the symptoms of, or prevents disease. Look for overblown claims on the label or box, such as "totally natural," "completely safe," or "miracle cure." If you're unsure about a product, ask your doctor or pharmacist. Or, call the supplement manufacturer and ask them what studies they've done to support the claims they're making.

Does the FDA regulate supplements?

Not in the way it regulates medicines. The FDA doesn't approve supplements before they are sold. Only after a product is on the market can the FDA go after companies if their products cause side effects, or they make false claims about their supplements.

What does the word "standardized" on a supplement label mean?

"Standardized" means that manufacturers ensure every batch of their products is produced in a consistent way, with the same ingredients. It does not necessarily reflect the quality of the product, however.

What is a 'proprietary blend?'

A "proprietary blend" is a combination of ingredients used exclusively by one supplement manufacturer. No other company produces the exact same combination of ingredients.

What is the difference between RDA and DV?

Recommended Dietary Allowance (RDA) is the amount of a certain nutrient you should get each day based on your age, gender, and whether you are pregnant or breastfeeding. On a supplement label, you're more likely to see the acronym DV, which stands for Daily Value. This represents how much of a nutrient the supplement provides in regards to a total daily diet. For example, if a calcium supplement is labeled "50% DV," it contains 500 mg of calcium per serving, because the DV for calcium is 1,000 mg per day. Sometimes the DV contained in a supplement will be higher than the RDA for certain people. Check with your doctor to make sure your supplement doesn't contain too much of any nutrient.

What should I do if I have a side effect from a supplement?

Report any side effects to your doctor, and to the FDA, as soon as possible. You can reach the FDA at (800) FDA-1088.

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