People with high levels of body fat stored in their belly or arms may be at a greater risk of developing neurodegenerative diseases like Alzheimer’s and Parkinson’s compared to those with lower fat levels in these areas, according to a study published in the Neurology journal on July 24, 2024.

The study also revealed that individuals with greater muscle strength have a reduced risk of these diseases compared to those with lower muscle strength.

“These neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, affect over 60 million people worldwide, and the number is expected to rise as the population ages.

Therefore, it is crucial to identify ways to modify risk factors to develop preventive tools,” said Dr. Huan Song, MD, Ph.D., from Sichuan University in Chengdu, China.

Dr. Song added, “This study suggests that improving body composition could help reduce the risk of these diseases. Interventions targeting the reduction of fat in the trunk and arms, along with promoting healthy muscle development, may be more effective than general weight control.”

The research involved 412,691 participants with an average age of 56, who were followed for an average of nine years.

At the study’s outset, various body composition measurements were recorded, including waist and hip circumference, grip strength, bone density, and fat and lean mass.

During the study period, 8,224 participants developed neurodegenerative diseases, mainly Alzheimer’s disease, other forms of dementia, and Parkinson’s disease.

Male participants with high belly fat developed neurodegenerative diseases at a rate of 3.38 cases per 1,000 person-years, compared to 1.82 cases per 1,000 person-years for those with low belly fat.

For female participants, the rates were 2.55 for high levels and 1.39 for low levels of belly fat. The term “person-years” accounts for both the number of people in the study and the duration each person participated.

After adjusting for factors like high blood pressure, smoking, drinking, and diabetes, the researchers found that people with high belly fat were 13% more likely to develop these diseases compared to those with low belly fat.

Those with high arm fat had an 18% higher risk of developing neurodegenerative diseases than those with lower arm fat. On the other hand, individuals with high muscle strength were 26% less likely to develop these diseases compared to those with low muscle strength.

The connection between body fat and neurodegenerative diseases was partly explained by the occurrence of cardiovascular diseases, such as heart disease and stroke, during the study period.

“This finding underscores the importance of managing cardiovascular diseases promptly to help prevent or delay the development of Alzheimer’s, Parkinson’s, or other neurodegenerative diseases,” Dr. Song emphasized.

A limitation of the study is that the participants were predominantly white individuals from the United Kingdom, so the results may not be generalizable to other populations. - Knowridge