A herbal supplement taken by thousands of Britons to keep their memory sharp into old age may do more harm than good.
Ginkgo biloba, first used medicinally by the Chinese more than 5,000 years ago, has been thought to stave off Alzheimer's disease and improve circulation. But research shows it increases the risk of a stroke, while its effects on memory are unclear. The U.S. study looked at the effect of three tablets a day on 118 men and women aged 85 and over. Half were given ginkgo biloba tablets or supplements and half were given placebos - dummy pills.
During the three-year trial, seven of those taking the supplement had a stroke or mini-stroke - but none of those in the placebo group did. Study author Dr Hiroko Dodge, an expert in age-related mental decline, said:
"Ginkgo has been reported to cause bleeding-related complications but the strokes in this case were due to blood clots, not excessive bleeding, and were generally not severe."
During the Oregon State University study 21 people developed memory problems which could be classed as dementia. Of these, 14 had taken placebos and seven the herbal supplement.
When the researchers took into account how well the volunteers had remembered to take their tablets, however, they found those who followed the instructions the best were 68 per cent less likely to have developed memory problems.
Source - Daily Mail