Ginkgo biloba has long been touted as an alternative therapy for improving memory or sharpening mental performance. But results of a new study suggest that the supplement may provide no additional benefit to elderly individuals with memory loss.

Dr. Martien C.J.M. van Dongen and colleagues conducted a study of 214 Dutch nursing home residents -- 63 patients with dementia and 151 patients with age-associated memory loss. The study participants were divided into three groups that were given daily doses of either 160 milligrams (mg) or 240 mg of ginkgo, or inactive (placebo) pills.

The investigators used various tests to measure improved mental performance, but after 24 weeks of treatment, they found positive effects only for self-perceived levels of activities of daily living and for the trail-making test, in which test takers are required to correctly assemble 30 numbers as quickly as possible.

In their report, published in the October issue of the Journal of the American Geriatrics Society, the researchers maintain that although initially statistically significant, "both effects were far from impressive" and were no longer evident after factors such as age and type of memory loss were taken into consideration.

Even when both the high-dose and the low-dose ginkgo groups were combined, no positive effect on mental status was noted, the report indicates. "Likewise, no significant beneficial effects were found for continued compared with discontinued use of ginkgo," the authors state.

Based on their results, the team asserts that using ginkgo biloba to treat older patients with mild to moderate dementia or age-associated memory impairment is ineffective, regardless of the dose.