Ginkgo Biloba: Wonder Herb For An Aging Brain?

Wednesday, October 11, 2006 - 3:01pm

The graying of America has brought herbs like Ginkgo biloba to center stage. For healthy, aging boomers, few things generate as much concern -- and dollars -- as the prospect of declining mental ability.

Brain booster - true of false?

Many supplements tout increased mental sharpness. Few, however, have the science to back up their claims. Ginkgo biloba, a common ingredient in many brain-booster formulas, may be an exception. Widely studied in Europe, and more recently in the United States, ginkgo has some health experts taking notice. The Journal of the American Medical Association published a study of ginkgo for treatment of dementia in October 1997. The National Center for Complementary and Alternative Medicine, a branch of the National Institute of Health, has plans for a large study of its effect on individuals with mild dementia.

Ginkgo Biloba and Alzheimers/dementia

The year-long JAMA study followed 309 patients with Alzheimer's Disease or dementia caused by loss of blood to the brain. They were given either 120 milligrams per day standardized Ginkgo biloba extract or a placebo. Those receiving ginkgo scored higher on mental and behavioral tests than those on the placebo. Although the improvements were modest, the authors concluded that the standardized ginkgo extract was safe and either stabilized or improved the mental and social functioning of these patients.

Only a small percentage of people with declining mental function will ever be diagnosed with Alzheimer's Disease. Ginkgo's usefulness for short-term memory function needs further study. The herb appears to be a strong antioxidant and protects blood vessels -- of the brain and likely elsewhere -- through its ability to decrease the stickiness of blood platelets. This has led some to project its effectiveness to general mental function, despite the lack of definitive studies.

History of Ginkgo Biloba

Ginkgo biloba has an interesting history. During the Ice Age, all members of the Ginkgoaceae family were wiped out except Ginkgo biloba. In the 200 million years since, it has become a popular ornamental tree throughout the world. Leaves are leathery and fan-shaped. Their two lobes resemble a simplistic rendition of the human brain. Dried and fresh leaves, and sometimes the seed, are used medicinally. The tree itself can live for hundreds of years, flowering only after its first 20 to 30 years of life.

Leaves are dried and processed to yield a standardized, concentrated extract. Unlike many herbal preparations, ginkgo products using the standardized extract contain a known, specific amount of the active compounds. However, not all ginkgo-containing products use the standardized extract -- something to look for on the label.

Is it safe for everybody?

While studies of the herb so far give it a wide margin of safety, some people have reported side effects such as mild gastrointestinal upset, headache and allergic reactions. Because of its effect on blood platelets, people at high risk for bleeding disorders or already taking blood-thinning medications might be advised to avoid gingko. It also is not recommended for people with epilepsy, because it can diminish the effectiveness of anticonvulsants.

Mental activity is still the recommended aid to short-term memory improvement

At this time, there is no magic memory bullet. Most experts recommend taking part in mental activities (word and memory games), cutting back on distractions like television and radio, and using aids such as lists, notes and organizational tricks -- like keeping keys in a specific place -- to enhance short-term memory.

Reprinted with permission from The Colorado State University Cooperative Extension Service.