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.

    美国研究人员表示：每天吃银杏叶，一种广泛使用的草药补充物，并不能防止认知功能减退、痴呆或老年患者的阿尔茨海默氏症。媒体周三的报道对此进行了引用。

    弗吉尼亚大学史蒂芬·迪科斯基和同事在美国医学协会期刊12月23/30号上报告称：吃了该补充物的老年患者，并没有比那些服用安慰剂的老年患者在记忆力、注意力、语言或其他认知能力量度方面有更小的下降。

    研究人员在2000年至2008年对3069名72岁以上的老人进行了诊查，他们中有一半每天两次服用120毫克的银杏叶，有一半服用安慰剂。

    研究人员发现，这两组在记忆力、注意力、视空间能力、语言或其他大脑功能改善方面并不存在差异。

    "如果有人认为银杏可以保持认知能力及预防或延缓与年龄有关的思维衰退，它并没有这样的功效。"史蒂芬·迪科斯基博士说。

    迪科斯基及其同事以前发现，银杏叶在减少老年痴呆症或痴呆症整体发病率上是无效的。

    银杏叶多年来一直被吹捧为当我们变老时，可保持和改善记忆和大脑功能的草药补充物。