Oily Fish May Reduce The Risk Of Alzheimer's
Linked to lower blood levels of beta-amyloid protein.
Eating fish, chicken, salad dressing and nuts may reduce the risk of developing Alzheimer's disease, according to new research.
US scientists found that eating foods containing omega-3 fatty acids was linked to lower blood levels of a protein related to Alzheimer's disease and memory problems.
The protein, beta-amyloid, accumulates in the brain of people with Alzheimer's in the form of plaques, and is also thought to cause nerve damage.
A team of scientists from Columbia University Medical Centre in New York studied the diets of 1,219 people over 65 without dementia for an average of 1.2 years, before testing their blood for the beta-amyloid protein,
They found that more omega-3 fatty acids a person had as part of their diet, the lower their blood beta-amyloid levels.
Those who ate a gram of omega-3 per day more than the average amount consumed by the people in the study had 20 to 30 per cent lower blood beta-amyloid levels. A gram of omega-3 is equal to approximately half a fillet of salmon per week, the researchers said.
None of the other nutrients the researchers looked at - including saturated fatty acids, omega-3 and omega-6 polyunsaturated fatty acids, mono-unsaturated fatty acid, vitamin E, vitamin C, beta-carotene, vitamin B12, folate and vitamin D - were associated with beta-amyloid levels in the blood.
The results stayed the same after taking into account age, education, gender, ethnicity, amount of calories consumed and whether the person had the APOE gene, a risk factor for Alzheimer's disease.
"While it's not easy to measure the level of beta-amyloid deposits in the brain in this type of study, it is relatively easy to measure the levels of beta-amyloid in the blood, which, to a certain degree, relates to the level in the brain," said study leader Dr Nikolaos Scarmeas.
"Determining through further research whether omega-3 fatty acids or other nutrients relate to spinal fluid or brain beta-amyloid levels or levels of other Alzheimer's disease related proteins can strengthen our confidence on beneficial effects of parts of our diet in preventing dementia."
Dr Anne Corbett, research manager at the Alzheimer's Society, said: "This isn't the first time that we've heard that good fats like omega-3 could reduce risk of dementia. Although this study didn't go as far as looking specifically at the condition, it adds weight to a growing body of evidence.
"However, the answer is not merely to enjoy the odd piece of fish or occasionally add some dressing to your salad.
"The best way to reduce your risk of dementia is to regularly eat an all-round balanced diet which could include these foods, as well as exercising often. It's also important not to smoke and to get your blood pressure and cholesterol checked regularly."