Dr. Elsabagh (2005) from King's College London found that ginkgo initially improved attention and memory. However, SMART X there were no benefits after 6 weeks, suggesting that a tolerance develops quickly. A recent randomized trial (DeKosky et al., 2008), conducted in 5 academic medical centers in the United States and including 2587 volunteers aged 75 years or older with normal cognition, showed that Gingko biloba at 120 mg twice a day was not effective in reducing the overall incidence rate of dementia.http://www.skinphysiciantips.com/smart-x/