Omega-3 oils lower risk of dementia

22 November, 2007

A diet that contains plenty of Omega-3 oils – like rapeseed oil, flaxseed oil, and walnut oil – can help reduce the risk of getting Alzheimer’s disease and other forms of dementia.

Omega-3 oils, which a study found can cut the risk of dementia by 60%, could help since the outer membranes of nerve cells are largely made up of these.

The study, in which over 8,000 people participated, has been published in the Journal of Neurology, the medical journal of the American Academy of Neurology.

Some of the studies conducted earlier had suggested that a diet rich in fatty fish such as tuna, mackerel, and herring is good for older people who are at risk of dementia.

The latest research observed 8,085 people, aged over 65, for nearly four years.

In the beginning of the study, the researchers studied the participants, who were from France, for signs of dementia and asked them to fill in a questionnaire about their eating habits. The examination was repeated every two years and, by the end of the study, 281 of the subjects had developed signs of dementia. These included 183 cases of Alzheimer’s disease.

From what they observed, the researchers drew three main conclusions – that Omega-3 oils (which most participants received through salad dressing) were linked to a 60% drop in the risk of dementia, that there was a 30% fall in dementia risk among regular eaters of fruits and vegetable, and that regular eaters of fish had a 35% less risk of Alzheimer’s disease (provided they did not have a known genetic risk factor for the disease.)

The gene that increases the risk of Alzheimer’s disease is called apolipoprotein E4, or ApoE4.

The study did not find that consumption of corn oil, peanut oil, lard, meat, or wine had any role in lowering the risk of dementia.

It has been estimated that the typical Western diet contains between 30 and 50 times more Omega-6 than Omega-3.

In the United Kingdom alone, about 500,000 people are believed to suffer from Alzheimer’s disease. Women are slightly more at risk than men, and the risk rises noticeably with age.

Before the age of 65, only 1 in 1,000 get Alzheimer’s disease, but in those over the age of 65, it is roughly 1 in 20. About half of those aged 80 and above have the disease.

According to scientists, the chances of getting Alzheimer’s disease mainly depend on one’s genes and lifestyle. The risk factors include high blood pressure, smoking, and high levels of cholesterol.