Taking Ginkgo biloba every day, a widely used herbal supplement, does not prevent cognitive decline, dementia, or Alzheimer's disease in elderly patients, U.S. researchers said as quoted by media reports Thursday.

    Older patients who took the supplement had no less a decline in memory, attention, language, or other cognitive measures than those on placebo, Dr. Steven DeKosky of the University of Virginia and colleagues reported in the Dec. 23/30 issue of the Journal of the American Medical Association.

    The researchers examined 3,069 people aged 72 or older between 2000 and 2008, with half of them taking 120 mg of Ginkgo biloba twice a day and half receiving a placebo.

    The researchers found that the two groups did not differ in terms of improvement of memory, attention, visuo-spatial ability, language or other brain functions.

    "If one thought that ginkgo might maintain cognition and prevent or delay decline in some thinking associated with aging, it did not do that," Dr. Steven DeKosky said.

    DeKosky and colleagues previously found that Ginkgo biloba was not effective in reducing the incidence of Alzheimer's dementia or dementia overall.

    Gingko biloba for years has been touted as an herbal supplement that can maintain and improve memory and brain function as we age.

    美國研究人員表示：每天吃銀杏葉，一種廣泛使用的草藥補充物，并不能防止認知功能減退、癡呆或老年患者的阿爾茨海默氏癥。媒體周三的報道對此進行了引用。

    弗吉尼亞大學史蒂芬·迪科斯基和同事在美國醫學協會期刊12月23/30號上報告稱：吃了該補充物的老年患者，并沒有比那些服用安慰劑的老年患者在記憶力、注意力、語言或其他認知能力量度方面有更小的下降。

    研究人員在2000年至2008年對3069名72歲以上的老人進行了診查，他們中有一半每天兩次服用120毫克的銀杏葉，有一半服用安慰劑。

    研究人員發現，這兩組在記憶力、注意力、視空間能力、語言或其他大腦功能改善方面并不存在差異。

    "如果有人認為銀杏可以保持認知能力及預防或延緩與年齡有關的思維衰退，它并沒有這樣的功效。"史蒂芬·迪科斯基博士說。

    迪科斯基及其同事以前發現，銀杏葉在減少老年癡呆癥或癡呆癥整體發病率上是無效的。

    銀杏葉多年來一直被吹捧為當我們變老時，可保持和改善記憶和大腦功能的草藥補充物。