Being overweight can do more to your head than just damage your self-image, it can literally damage your brain.
As far as this subject is concerned, there are two things that we already know. First off, it's long been established that our brains naturally shrink and lose white matter (the part that transmits information) with age. Similarly, obesity has already been linked to conditions such as diabetes, cancer and heart disease. However, the latest study has found that obesity and the aging of our brains are connected; specifically, that being overweight ages your brain to look 10 years older than that of a skinnier person's who is the same age.
In a study published in the journal Neurobiology of Aging, researchers from the Cambridge Centre for Ageing and Neuroscience analyzed 473 people between the ages of 20 to 87 and divided them into two categories, depending on their weight: lean and overweight. In the end, they found that overweight people had less white matter in their brains compared with their leaner counterparts.
From there, they calculated how white matter volume relates to age across the two groups. In doing so, they found that an overweight person had a white matter volume comparable to a lean person who is 10 years older than them.
Interestingly enough, however, they only found this to be the case in people who are middle-age and above, giving credence to the belief that our brains are particularly vulnerable during that period of aging.
"The fact that we only saw these differences from middle-age onwards raises the possibility that we may be particularly vulnerable at this age," said senior author Professor Paul Fletcher in the report. "We're living in an aging population, with increasing levels of obesity, so it's essential that we establish how these two factors might interact, since the consequences for health are potentially serious."
However, while researchers now know what obesity can do to people in those age groups, they still don't know why that is the case.
"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," Dr. Lisa Ronan of the Department of Psychiatry at the University of Cambridge, said. "We can only speculate on whether obesity might in some way cause these changes or whether obesity is a consequence of brain changes."
Similarly, they still don't yet know the full implications of these changes in brain structure. "This must be a starting point for us to explore in more depth the effects of weight, diet and exercise on the brain and memory," the report stated.
There was one last interesting thing that was discovered during the course of this study. Despite the differences in the volume of white matter between lean and overweight individuals, there was no apparent connection between being overweight or obese and an individual's intelligence or cognitive functions.
