Professor Toshiharu Ninomiya, from Kyushu University in Japan, stated that the effectiveness of a healthy lifestyle in preventing dementia depends largely on an individual's genetic makeup.
According to him, controlling blood pressure and blood sugar levels, maintaining weight, quitting smoking, and engaging in physical activity all contribute to reducing the risk of developing dementia, but the strength of this effect may vary depending on the individual's genetic makeup.
Professor and colleagues analyzed data from 9,605 Japanese people over the age of 65, studying the interaction of the ε4 variant of the APOE gene (responsible for fat metabolism and brain function) with modifiable risk factors associated with dementia, such as high blood pressure, diabetes, low body mass index, history of stroke, smoking, and lack of physical activity.
The APOE ε4 variant is one of the strongest genetic risk factors associated with Alzheimer's disease, as an individual can inherit one copy of it from one parent or two copies from both.
The professor said: "Following a healthy lifestyle and controlling modifiable risk factors may be associated with a reduced risk of dementia in people who carry one copy of the APOE ε4 gene."
However, the study did not show a similar clear association among carriers of two copies of the gene.
Although the professor did not rule out the possibility of a statistical error due to the small number of participants in this category, he pointed out that the genetic influence is stronger in them, and that traditional lifestyle interventions and control of risk factors may not be sufficient, given their significantly higher risk of developing dementia.
