Vitamins, Minerals and Supplements

by Christina Medvescek on September 1, 2003 - 12:34pm

General information

Although they may contribute to good health, vitamins and other supplements aren't regulated as drugs but as food products — meaning quality can vary widely, and you can buy them without prescriptions.

In recent years, the industry has attempted to police itself with voluntary certifications. These "quality seals" vouch for the product's manufacturing process, ingredients, dosage strength, purity, potency, consistency and "bio-availability" (how well the formula can be used by the body). But the seals don't certify that the product is safe or effective for you and your particular condition.

Warnings and guidelines

  • Beware of cure-alls, products with "secret" ingredients, and sellers who won't send you their research reports.
  • Look for Internet sites that follow the same practices as reputable online pharmacies.
  • Compare shipping costs as well as product prices.

Supplements resources

  • National Center for Complementary and Alternative Medicine has clinical studies of ingredient effectiveness. Go to or call (888) 644-6226.

Quality seals include:

USP, from the nonprofit firm U.S. Pharmacopeia. Be sure the product bears the actual symbol, not just the letters "USP," which indicates that the manufacturer follows USP guidelines, not that USP has certified the product.

GMP, from the National Nutritional Foods Association (NNFA). Certification is available only to NNFA members.

NSF International uses the same criteria as GMP, but is available to non-NNFA members., a for-profit program, does independent product testing and provides results to subscribers. The use of its seal isn't widespread as yet.

Supplement Price Comparison
Vitamin, Mineral, Supplement1
$4.95 shipping
per order
$5.49 shipping
per order
$5.49 shipping per order
In-store purchase
Not sold online
400 IU
d-alpha tocopheryl acetate
Natrol Natural E D Alpha
$.01 per pill
GNC Natural E $.06 per pill Walgreens Finest Natural E D Alpha $.12 per pill Spring Valley Natural E $.06 per pill
100 mg
Country Life $.52 per pill Natrol $.38 per pill Natrol $.44 per pill Spring ValleyQ Sorb (with E) $.40 per pill
Schiff Move Free $.26 per pill Rite Aid Double Strength $.09 per pill ArthX $.20 per pill Spring Valley $.13 per pill
500 mg(or closest dose)
Natures WayCalCitrate $.08 per pill PharmAssureCalcimate (+D) $.08 per pill Citracal +D(250 mg) $.09 per pill $.18 per dose Spring Valley(315 mg) $.05 per pill
$.10 per dose 
TOTAL $.87 $.61 $.94 $.69

Compared products have the same ingredients and dosage strength, a quality seal or store brand, and are the cheapest available on the site or in the store. Per-pill prices have been rounded off.

2Purchased in Tucson, Ariz.

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