Being Fat Hurts Your Brain

Being fat could make you lose your mind, recent research suggests. One recent long-term study found that overweight people experienced a much more pronounced and rapid decline in brain functions, writes Olivia Judson at the New York Times Opinionator blog. Another found that middle-aged obese people have smaller, more atrophied brains than the thin—and that atrophy is a leading feature of dementia. Still another study noticed that even among the young and healthy, fatter people had lower brain-matter density.

The effect could be a genetic one—there appears to be one gene tied strongly to both body weight and brain functions—or it could be a result of the fat tissue itself, which secretes hormones that have been linked to Alzheimer's. Even diet could play a role—lab mice given high-fat diets displayed increased brain inflammation. But whatever the reason, this bodes poorly for a US population where 33% of adults are obese. (More obesity stories.)