From middle age, the brains of obese individuals show signs that it is 10 years older than those in lean individuals, according to a study revealed Thursday by the University of Cambridge.
Human brains naturally shrink with age, but scientists are increasingly recognizing that obesity may also affect the onset and progression of brain aging. Now a new study led by researchers from the University of Cambridge may provide new evidence to support this link.
The team studied data from 473 individuals between the ages of 20 and 87, and divided the data into two categories based on weight: lean and overweight. They found striking differences in the volume of white matter in the brains of overweight individuals, compared with those of their leaner counterparts. Overweight individuals had a widespread reduction in white matter compared to lean people.
White matter is the tissue that connects areas of the brain and allows for information to be communicated between regions.
The team then calculated how white matter volume related to age across the two groups. They discovered that an overweight person at, say, 50 years old had a comparable white matter volume to a lean person aged 60 years, implying a difference in brain age of 10 years.
But the researchers only observed these differences from middle-age onwards, suggesting that brains may be particularly vulnerable during this period of aging.
"It will also be important to find out whether these changes could be reversible with weight loss, which may well be the case," said one of the study authors, Professor Paul Fletcher from the University of Cambridge.
The study has been published in the journal Neurobiology of Aging.