Researchers have found that a particular type of body fat is linked to the abnormal proteins in the brain that are hallmarks of Alzheimer’s disease, up to 20 years before the first symptoms appear. The study is being presented at the annual meeting of the Radiological Society of North America.

The research team, led by the Mallinckrodt Institute of Radiology at Washington University School of Medicine in St. Louis, Missouri, focused on the relationship between modifiable lifestyle factors, such as obesity and body fat distribution, and the pathology of Alzheimer’s disease.

The study involved 80 mentally healthy middle-aged subjects (mean age 49.4 years), of whom approximately 57.5% were obese.

The association of body mass index, visceral fat, subcutaneous fat, fat in the liver, thighs and muscles, HDL (good cholesterol) and insulin resistance with the deposition of amyloid and tau protein in the brain was investigated in the participants. which occurs in Alzheimer’s disease.

The findings revealed that higher levels of visceral fat were associated with increased amyloid, while other types of fat were not associated with increased Alzheimer’s disease pathology.

Cerebral blood flow imaging in subjects with and without obesity and in subjects with high and low visceral adipose tissue

Also, higher insulin resistance and lower HDL are associated with high levels of amyloid in the brain. In subjects with higher HDL the effects of visceral fat on amyloid pathology were partially reduced.

A second study presented by the research team at the same conference also found that obesity and visceral fat reduce blood flow to the brain.

The researchers point out that lifestyle modifications aimed at reducing fat could affect the development of Alzheimer’s disease.