Research has linked a higher body mass index in young adults with a poorer ability to remember past events. By middle age, the accumulated damage puts people with obesity at higher risk of dementia than their peers, according to the American Heart Association. Research also has linked a higher BMI to lower blood flow in the five regions of the brain that can be affected by Alzheimer’s disease.
The most recent study, published [January 31], found similar patterns of shrinkage in the brain regions responsible for learning, memory and judgment among middle-aged obese people and Alzheimer’s patients. This was the first research to make a direct comparison.
It’s not exactly clear how obesity can cause the loss of brain cells, but scientists believe chronic inflammation plays a role. Obesity-related inflammation in the body breaches the blood-brain barrier between the periphery and central nervous systems, causing neuroinflammation.
But other conditions associated with obesity, including high blood pressure, high cholesterol and type 2 diabetes, also can damage blood vessels in the brain and lead to cell death. This makes identifying direct causal links more difficult. And some studies suggest that lower cognitive functioning leads to poor eating behaviors – not the other way around.
