This white matter is important as it allows the nerve cells in the brain to communicate more efficiently.
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They found that those people who were overweight had a much less white matter volume than those of the same age in the lean group – in other words, an overweight person had a brain 10 years older than that of their lean counterpart. She further said that they can only speculate on whether obesity might in some way cause these changes or whether obesity is a outcome of brain changes. Being overweight and severely overweight can cause very similar and sometimes identical changes.
While it has always been known that human brains naturally shrink with age, scientists are increasingly recognizing that obesity may also affect the onset and progression of brain ageing.
“In short, the growing body of literature that relates common markers of aging to those observed in obesity supports the hypothesis that obesity may accelerate or advance the onset of brain aging”, wrote University of Cambridge’s Lisa Ronan, PhD, and colleagues. This infers that for younger people who are overweight then the trajectory can be changed provided lifestyle changes are implemented. A definite cause and effect relationship has not yet been established, but the relationship has definitely been suggested by the findings of the researchers. This was to the extent that with a lean person and an obese person of the same age, the brain of the obese person resembled that of a lean person who was ten years older.
The study’s participants were 473 men and women, all from Cambridge, England, MedScape reported.
Ronan and her colleagues focused on almost 500 men and women between the ages of 20 and 87.
About half were “lean” (at a body mass index or BMI between 18.5 and 25).
While they found less white matter suggestive of a brain-age increase of 10 years, Ronan says they did not find any proof that this had an effect on cognitive ability. After separating the subjects into two groups by BMI (lean and overweight), they calculated the mean difference in age between every white matter volume.
After dividing the data into two categories – lean and overweight – the scientists found striking differences in the volume of white matter.
One drawback to the study is that it did not follow participants over a period of time.
Sheline said Ronan’s team “only looked at obesity as an overall measure and didn’t take into account the distribution of fat”.
The researchers concluded, after analyzing the results of their study, that the shrinkage of white matter in brains appears to be linked with how overweight or obese a person is, particularly in the case of middle-aged participants.
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Other studies have found a link between obesity and a decline in thinking skills, as well as getting Alzheimer’s disease at an earlier age.
