Men with high levels of belly fat are at increased risk of dementia, according to a new study by Monash University researchers of more than 17,000 individuals aged 65 to 98 years in the ASPREE Study.
Importantly the study also found that the risk for dementia is up to 38 per cent lower in those with higher lean body mass and, perhaps surprisingly, more fat body mass.
The study, published in the Journal of the American Alzheimer's Association, found that dementia risk was 15 to 38 per cent lower for individuals in higher quartiles of lean or fat body mass.
Professor Joanne Ryan, who heads the Biological Neuropsychiatry and Dementia research unit in the School of Public Health and Preventive Medicine at Monash, was a senior author on the study.
"Higher lean body mass and fat body mass in later life may be associated with better cognition, while abdominal fat could be a risk factor, particularly in men," the study said.
Excess body weight, especially in midlife, is considered a risk factor for numerous health conditions, including diabetes and cardiovascular disease, which in turn are risk factors for dementia and cancer.
"Our findings suggest that increased body weight in older age may confer protective effects on brain aging, regardless of body composition. However, abdominal adiposity may still be a risk factor for cognitive impairment in older individuals, particularly in men," Professor Ryan said.
"These findings suggest that avoiding excess fat accumulation in the abdominal area and maintaining a balance between lean and fat mass may be beneficial to cognitive function in older age. Lifestyle strategies, such as a healthy diet and regular exercise, likely play a role in protecting brain health for older individuals."
Read full paper in the Journal of the American Alzheimer's Association: Associations of abdominal adiposity, lean body mass, and fat body mass with dementia and cognitive change in older age. DOI:10.1002/dad2.70135