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WHITE PLAINS, NY — MARCH 14, 2005 — reported test results today for a wide variety of vitamin C supplements purchased at retail. Vitamin C is the top-selling single vitamin in the U.S., with sales of $770 million in 2003 according to Nutrition Business Journal. All of the 29 products in the report met their claims for vitamin C and all tablets disintegrated properly for absorption. However, found that three products suggested doses that could cause side effects in some individuals. Results were similar to those from 2003 but better than those from 2001, when several products contained less vitamin C than claimed and one product would not disintegrate properly.

Vitamin C helps build collagen, aids iron absorption, and, as an antioxidant, may protect the body and boost the immune system when under stress. Recommended daily intake levels (developed by the Institute of Medicine and provided in the report) range from 15 mg for very young children to 120 mg for women who are nursing. An additional 35 mg/day is recommended for smokers, whose vitamin C stores may be depleted. Consumers should be aware, however, that diarrhea and other side effects may occur with consumption of too much of the vitamin. Vitamin C can also affect the absorption and/or metabolism of other nutrients or drugs and may interfere with diagnostic tests such as that for blood in stool.

The new report is found at Test results are shown for each product. Products include those made with vitamin C from Ester-C®, sodium ascorbate, and natural sources such as rose hips (the pear-shaped fruit of the rose) and/or acerola (a cherry-like fruit). Two of the products are marketed for children. selected seventeen of the products. Twelve others are included for having passed the same testing through's Voluntary Certification Program.

Reviews of other popular types of supplements are also available at Reviews soon to be released include omega- 3 & 6 fatty acids (from black current, borage, evening primrose, and flaxseed oils), supplements used for menopause (including isoflavones, progesterone cream, and black cohosh), nutrition powders and drinks, B vitamins, and magnesium. The paperback's Guide to Buying Vitamins and Supplements: What's Really in the Bottle? is available in bookstores, online from or through 800-431-1579. is a leading provider of consumer information and independent evaluations of products that affect health and nutrition. The company is privately held and based in White Plains, New York. It has no ownership from, or interest in, companies that manufacture, distribute, or sell consumer products. is affiliated with (, an evaluator of online pharmacies. Subscription to is available online. For group subscriptions, Technical Reports, or product testing contact Lisa Sabin, Vice President for Business Development, at

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