Adults on Mediterranean diet have bigger brains than those who eat junk food

Following this diet could help prevent dementia, after researchers found a telling difference in adults who regularly eat junk food.

Middle-aged adults who have a healthy diet have larger brains. Picture: Jay Town

Middle-aged adults who eat a healthy diet have larger brain volumes compared to those who load up on junk, fats and sugars, suggesting the chance to reduce our dementia risk starts from our 40s.

Deakin University researchers looked at the diets and brain scans of almost 20,000 UK adults, scoring participants on how well their meals aligned with the Mediterranean Diet.

This eating style is heavy in wholegrains, fish, fruit, vegetables and healthy oils, while limiting processed foods and meat.

Those aged 40-65 years who ate a healthy variety of foods had the most grey matter and larger brain volumes.

Diet was more influential on the brain volumes of men.

Lead researcher Dr Helen Macpherson from Deakin’s Institute for Physical Activity and Nutrition, said while other studies had shown the importance of a healthy diet in later life on brain volume, theirs was the first study to show the effect in midlife.

“It’s really telling us that diet is important early in life, probably earlier than we thought in relation to dementia risk. We really need to be getting onto it during midlife,” Dr Macpherson said.

“We know that brain volume does decline as we get older and that brain shrinkage, even in midlife, is a risk factor for getting dementia later in life.

“This is important because we don’t have a blood test for dementia during midlife. But looking at things like brain volume can help give us some information about people’s later risk of dementia.

“The most optimistic thing was that this wasn’t a fad diet. It was just healthy eating. There was nothing complicated about it. It was the same diet you’d follow to reduce heart disease or stroke, or anything else.”

This cohort of middle aged adults will continue to be followed by researchers to see who goes on to develop dementia later in life, a finding that will add further evidence about the important of lifelong healthy eating on later brain health.

In the meantime, Deakin researchers are testing the impact of a Mediterranean diet on the cognition of older adults.

The findings were published in the Journal of Alzheimer’s disease.