The results of a study by researchers at the University of Bari, Italy, which involved 1,445 people, aged 65 to 84, suggests that those patients who drank one alcoholic drink a day developed dementia including Alzheimer's disease, at a slower rate than people who never drank alcohol.

Of the group 121 had mild cognitive impairment which is the stage between normal ageing and dementia; symptoms include mild memory or mental problems but no significant disability.

The researchers measured the alcohol consumption and brain functioning and discovered that in those patients who drank one alcoholic drink a day, usually a glass of wine, the rate dementia developed was 85 per cent slower than for people who never drank alcohol.

The researchers say the study is the first to look at how drinking alcohol affects the rate of progression to dementia and they suggest that the development of dementia could be slowed during the early stages of dementia.

The study participants were part of the Italian Longitudinal Study on Ageing and were tracked for three and a half years by which time the researchers saw a trend linked to drinking alcohol.

Dr. Vincenzo Solfrizzi and Dr. Francesco Panzafrom the University's department of geriatrics, say it is unclear how low alcohol consumption appears to protect against the progression of dementia but suggest it is possible that alcohol may guard against dementia because it is good for the circulation and may stop hardening of the arteries in the brain.

Dr. Solfrizzi says their findings support other research which indicates that drinking moderate amounts of alcohol may protect the brain from stroke and vascular dementia.

Experts however, while they acknowledge the possible benefits of moderate alcohol consumption in relation to dementia, caution against people interpreting the research to mean they should drink more alcohol to protect themselves; they urge people to adopt a healthy lifestyle with a healthy diet, physical exercise, mental stimulation, along with social interaction, in order to protect against dementia.

Alzheimer's organisations are reportedly investigating the possible links between the effects of foods such as fruit juice, red wine and oily fish and the incidence of mental illness.

Experts have already proved that wine contains high levels of flavonoids, natural compounds which have an antioxidant effect, which are good for the circulation.

Experts have also been warning for some time that health and social services could be overwhelmed in the future by the vast numbers of people expected to develop dementia.

They say the study is interesting because it examines the link between people already experiencing mild cognitive impairment and the impact of drinking alcohol, and state that the message is "little and often" for people wanting to protect their memory - as high levels of alcohol consumption can also lead to dementia. Previous research from the French wine region of Bordeaux has shown that people with the highest consumption of red wine reduced their risk of dementia by 45 per cent. The study published in the journal Neurology.