Gingko biloba has no beneficial effect on memory in healthy older people, according to a US study.
The popular herbal supplement is extracted from leaves of the gingko biloba tree. It is widely believed to enhance memory and concentration, and sales in the US alone exceed 拢200 million each year.
鈥淢any of our older patients were taking gingko and wanted to know if it was of any benefit. But although there had been dozens of trials showing beneficial effects, they all had serious shortcomings. We decided to carry out the first scientifically rigorous study,鈥� said Paul Solomon who led the study at Williams College in Williamstown, Massachusetts.
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Solomon鈥檚 team studied 230 adults over the age of 60 who were physically and mentally healthy. They found no memory improvements after six weeks of daily gingko supplementation.
鈥淚t doesn鈥檛 surprise me because we don鈥檛 know how gingko works and data on herbal remedies is often not clear,鈥� said Lawrence Wilkinson an expert on cognitive function at the Brabraham Institute.
Memory worries
The participants were given 14 standardised tests of learning, memory, attention and concentration. Half of the group were then given daily gingko biloba tablets for six weeks while the rest received a placebo.
The team found no difference in performance between those who had taken gingko and those who had not, despite the manufacturer鈥檚 claims that beneficial effects on memory should appear after just four weeks.
鈥淚 went into the study with an open mind, but we found no evidence that gingko benefits memory or learning,鈥� Solomon told 快猫短视频.
Kim Graham a researcher in the Memory and Knowledge Group at the Medical Research Council鈥檚 Cognition and Brain Sciences Unit was also unsurprised by the findings. 鈥淟ots of people worry about their memory and so are willing to try various remedies, but I am pretty sceptical about the benefits,鈥� Graham said.
Journal reference: Journal of the American Medical Association (vol 288, p 835)