Large Waist in Normal-Weight Seniors Tied to Higher Dementia Risk

A study in Obesity suggests older adults with normal weight but a wider waist may be more vulnerable to developing dementia, reports Reuters Health . The research does not prove that extra fat around the waist causes dementia in healthy-weight individuals, although dementia rates climbed consistently among older adults with a normal body mass index (BMI), along with waist sizes of at least 90 centimeters for men and 85 centimeters for women. The researchers argue that waist circumference is a better indicator of excess fat than BMI, especially in seniors, who tend to lose lean body mass and increase fat without a change in weight. Normal-weight participants with abdominal obesity had a significantly elevated risk, while those who were overweight or obese had a lower risk of dementia than normal-weight individuals. However, underweight subjects actually had the highest risk. The University of California, San Francisco's Katherine Possin thinks increased dementia risk in underweight people may stem from underlying medical conditions, while people who are overweight likely have maintained their lean muscle mass.