25 October 2002
France France (October 25, 2002) - Eating fish or seafood at least once a week lowers the risk of developing dementia, researchers have found. A team of French researchers asked elderly people about their eating habits, and found a link between eating fish, which has high levels of polyunsaturated fatty acids and a reduced risk of dementia, including Alzheimer's disease. Over 1,670 people aged 68 or over living in south west France took part in the survey. They were all taking part in a long-term study of how age affects mental function and behaviour. They were classed as eating meat or fish every day, at least once a week (but not every day), from time to time (but not every week), or never. Researchers went back to talk to the study participants two, five, and seven years later. They were asked about how often they ate fish, and meat - which is rich in saturated fatty acids. It was found those who ate fish or seafood at least once a week had a significantly lower risk of developing dementia over the seven years of the study. Education Fatty acids in fish oils have a protective effect on the vascular system, and the researchers say they could also reduce inflammation in the brain and have a specific role in brain development and regeneration of nerve cells. The protective effect of fish appeared to be less strong for more highly educated people. They said this could be because they developed healthy eating habits when young which could be linked with higher educational achievements, or because they follow recommendations on how much fish to eat more closely. No significant link was seen between eating meat and a risk of dementia. Pascale Barberger-Gateau of the University Victor Segalen in Bordeaux who led the study, said: "Elderly people who eat fish or seafood at least once a week are at a lower risk of developing dementia, including Alzheimer's disease."
Longer study Harriet Millward, deputy chief executive, Alzheimer's Research Trust told BBC News Online: "The suggestion that fish consumption may protect against dementia has been around for some time. "For instance, Japanese people who emigrate to other countries where they eat much less fish than in Japan, suffer higher rates of dementia. "There has also been one large study, the Rotterdam study, which found that fish consumption protected against dementia and particularly Alzheimer's." She added: "This new research from another well-known epidemiological group is also important. "Though not as large as the Rotterdam study, they followed people for longer, which is valuable. "Their results confirm the earlier findings that eating fish or seafood at least once a week reduces the risk of dementia, including Alzheimer's. "This would therefore seem to be another of the many factors influencing the risk of this devastating disease." The research is published in the British Medical Journal.
