Eating a diet that's rich in carbohydrates-like sweets, soft drinks, bread, pasta and potatoes-is a direct cause of mild dementia and memory loss as we get older. Such foods increase the risk fourfold, while sugars are the second biggest cause of cognitive impairment, which is often considered a forerunner of
severe dementia and Alzheimer's.
A diet that's high in fats and protein is far less likely to cause mental decline, say researchers from the Mayo Clinic.
Their findings are some of the most emphatic ever made about diet and mental sharpness, and their 400 per cent association is as close as we'll get to establishing that carbohydrates are definitely a cause.
The researchers reckon that carbs interfere with the body's ability to metabolize glucose and insulin, which are needed to 'feed' the brain. The same can happen when we eat too much sugar.
The carbohydrate link was discovered when the researchers analyzed the lifestyles and diets of 937 people aged 70-89 years. They found that those who ate the most carbohydrates were 3.6 times more likely to show mild cognitive decline, including problems with memory, language, thinking and judgement.
Those who ate more fats were 42 per cent less likely to suffer such a decline, while those with high-protein diets had the lowest risk at 21 per cent.
J Alzheimers Dis, 2012; 32: 329-39