A chemical found in red wine helps slow dementia, say scientists - but you would have to drink 1,000 bottles a day to get enough of it.
Researchers studied the effect of resveratrol, found in red grapes, on people with mild to moderate Alzheimer's.
They said the drug - also seen in raspberries, dark chocolate and peanuts - "may have some positive effects" on helping patients complete day-to-day tasks, such as "using the telephone and cooking at home".
The chemical was also found to stop the levels of key protein amyloid beta 40, known as a "biomarker", falling in the blood and spinal fluid of Alzheimer's sufferers. Levels of the biomarker usually fall as the disease progresses, but the levels of those who took resveratrol in the clinical trial remained steady - suggesting the drug may affect the underlying process that causes Alzheimer's.
In the year-long study by Georgetown University Medical Centre in Washington DC, pure synthetic resveratrol was given to some of the 119 participants.
The highest dose tested was one gram twice a day - equivalent to the amount found in about 1,000 bottles of red wine.
Out of four cognitive tests, the researchers found an improvement among resveratrol patients on a measure called the day-to-day living scale, which looks at how patients cope with household activities. The results, published online by the journal Neurology, were described as "very interesting" by the researchers.
But lead investigator Dr R. Scott Turner warned the findings cannot be used to recommend resveratrol without further research.
He said: "This is a single, small study with findings that call for further research to interpret properly.
"We can't conclude from this study that the effects of resveratrol treatment are beneficial."
However Dr Turner said the study concluded resveratrol was safe and well tolerated by the body. The most common side-effects experienced by participants included nausea, diarrhoea and weight loss. Further studies are now under way.
- Daily Mail