Mid-life obesity is making your brain older by 10 years

Turns out, mid-life obesity risks not only the body, but also the brain.

From middle-age, the brains of obese individuals display differences in white matter similar to those in lean individuals ten years their senior, according to a new research led by the University of Cambridge. White matter is the tissue that connects areas of the brain and allows for information to be communicated between regions.

In a cross-sectional study, researchers looked at the impact of obesity on brain structure across the adult lifespan to investigate whether obesity was associated with brain changes characteristic of ageing. The team studied data from 473 individuals between the ages of 20 and 87, recruited by the Cambridge Centre for Aging and Neuroscience.

Despite the clear differences in the volume of white matter between lean and overweight individuals, the researchers found no connection between being overweight or obese and an individual's cognitive abilities, as measured using a standard test similar to an IQ test.

"As our brains age, they naturally shrink in size, but it isn't clear why people who are overweight have a greater reduction in the amount of white matter," said first author Dr Lisa Ronan, "We can only speculate on whether obesity might in some way cause these changes or whether obesity is a consequence of brain changes."

Senior author Paul Fletcher added: "The fact that we only saw these differences from middle-age onwards raises the possibility that we may be particularly vulnerable at this age. It will also be important to find out whether these changes could be reversible with weight loss, which may well be the case."

The results are published in the journal Neurobiology of Aging.