WESTCHESTER COUNTY, NEW YORK — TUESDAY, JANUARY 3, 2006 — In its new test report on Memory Enhancement Supplements, has revealed finding significant amounts of lead in certain products on the market. The lead was found in supplements made with a specific form of the herbal ingredient Ginkgo biloba. also reported finding no active ingredient in a product claiming to contain huperzine A, an ingredient of potential benefit in people with Alzheimer's disease. A different huperzine A product passed the testing as did several products made with the ingredients phosphatidlyserine or acetyl-L-carnitine, which also have potential memory-enhancing effects.

Ginkgo is the most popular ingredient in supplements for memory enhancement, with sales exceeding $100 million in 2004 according to Nutrition Business Journal. However, of the thirteen ginkgo products that CL selected for testing, only six passed its review — meeting criteria for ingredient purity, quantity, and identity. Two of the failing products had the highest daily levels of lead that has encountered in its tests of over 1,500 products over the past six years: Daily servings of these supplements yielded more than 12 and 16 micrograms of lead, respectively. These amounts are far higher than 0.5 microgram limit set by the State of California for the sale of supplements without a lead warning. Low levels of lead are found many foods and beverages, but the amount of lead in a daily dose of the pills is close to that to which an adult would be exposed from all food and drink consumed in a week.

In adults, lead can cause elevated blood pressure, anemia, and adversely affect the nervous and reproductive systems. In children, infants, and fetuses, even low levels of lead can adversely affect neurobehavioral development and cognitive function. Lead is of particular concern during pregnancy as the mother can transfer it to the fetus. It is believed that some risk exists with any level of lead exposure and should be avoided, particularly because lead builds up in the brain, bone, and kidneys. The lead in the supplements may not, however, in themselves, cause symptoms in adults: According to the FDA, tolerable daily lead consumption from the total diet is 6 mcg for young children, 25 mcg for pregnant and nursing women, and 75 mcg in adults.

A possible clue to the lead problem was that only products that contained gingko leaf powder (i.e., made from the whole dried leaf) were contaminated. Those made only with gingko from leaf extract were not contaminated. The extraction process may remove potential contaminants.

In addition to the lead problem, all of the contaminated products and several others were found to be deficient in key compounds expected in ginkgo — suggesting that they contained less ingredient than promised or were made with poor quality material. Three products, for example, had half to two-thirds of the expected amount of bilobalide, a compound of potential importance in ginkgo's effectiveness. Bilobalide is known to enhance the excitability of neurons in the hippocampus of the brain, which is associated with learning and memory.

A recall of one of the ginkgo products was announced last week (see 12/31/05 posting at

The testing included popular products such Ginkgoba and Ginkgo-Go as well as products by AARP, Canadian Sun, Good 'N Natural, Irwin Naturals, Jarrow, Life Enhancements, Maxi-Health, Nature's Plus, Olympian Labs, PharmAssure, Solaray, TruNature, and Wildoats.

In addition to the products selected by, eight products are included in the reports for passing the same testing through's Voluntary Certification Program. These products are from Nutrilite, Nature's Bounty, Puritan's Pride and Vitamin World.

Tod Cooperman, M.D., President of, urged consumers to check its listings before considering a supplement for memory enhancement and he offered the following additional advice:

  • If buying a ginkgo product, look for those made exclusively with ginkgo extract to help avoid potential lead contamination. Ideally these should be standardized to contain 24% flavone glycosides and 6% terpene lactones — but these claims are not always true.
  • New or severe problems with memory or thinking can be symptoms of a serious medical condition, so check with your doctor before self-treating.
  • Be aware that these ingredients can interact with medications, such as blood thinners and medications for Alzheimer's disease — described in more detail in the report.


The new report is available at The report provides results for each product, ingredient comparisons, expert tips on buying and using these supplements, and potential side effects. Reviews of other popular types of supplements are also available at New Reviews to be released in coming weeks include calcium and vitamin D, prostate supplements (saw palmetto and beta-sitosterol), probiotics, and supplements used for sexual enhancement. The paperback's Guide to Buying Vitamins and Supplements: What's Really in the Bottle? is available in bookstores, online, 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 Westchester, 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, and, which reviews and rates Medicare Part D plans. Subscription to is available online. For group subscriptions or product testing contact Lisa Sabin, Vice President for Business Development, at

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