How Can I Verify Which Vitamins Are Better?

Consumers who purchase vitamins want to be able to verify the quality, safety and potency of these products. In 2007, the Food and Drug Administration set June 2010 as the date by which all manufacturers of dietary supplements must meet quality standards, including accuracy of ingredients on labels and absence of contaminants (bacteria, lead, glass and pesticides). Two independent organizations already offer voluntary labeling programs. Reading and understanding product labels is helpful in verifying which vitamins are better.

Locate the expiration date on the bottle or package by the initials "Exp." Over time, vitamins lose their potency and should be discarded.

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Locate "Supplement Facts" on the label. Each vitamin listed should provide around 100 percent of the daily value (%DV). Greater amounts are unnecessary. Manufacturers are unable to place 100 percent of DV of calcium in a product. It would be too large to swallow and calcium ideally should be divided throughout the day.

Locate the initials "USP" (U.S. Pharmacopeia), the "USP Verified" seal or the letters "NSF" (NSF International) on the label. These markings verify the manufacturer is complying with good manufacturing practices, product safety and proper labeling. In addition, the USP seal verifies the product has been independently tested for purity, potency and how quickly it dissolves in the stomach.

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Investigate specific brands of vitamins online by visiting the USP Verified Dietary Supplements or NSF Certified Dietary Products websites (see Resources).


Independent programs do not verify the effectiveness of a vitamin supplement for an individual. Consumers are encouraged to speak with a health-care professional about personal use of vitamins.

The lack of the USP Verified seal does not mean the product is inferior. The USP and NSF programs are voluntary and manufacturers must pay a fee to have testing done.

The American Dietetic Association promotes eating a wide variety of foods to optimize health and reduce the risk of chronic disease. When this is not possible, or specific nutrient needs increase, such as during pregnancy, vitamins help fill dietary gaps


Some vitamins interfere with the action of prescribed and over-the-counter medications. Consult a physician, pharmacist or other health professional about proper use of vitamin supplements.

The USP label is not the same as the USP Verified seal. The seal means the product has been tested by the U.S. Pharmacopoeia Verification Program.