What helps to reduce risk of dementia?
It is repeatedly proven, that exercise and healthy eating can protect from dementia. But the explanations why this is so, were superficial and only partially satisfactory. Now a study provides evidence further.
It is known fact that high blood pressure and high cholesterol levels increase the risk of dementia. Since both can be lowered through regular Sport exercise of course positively affect on the risk reduction of dementia disease. But only this fact does not seem to explain the positive impact of sport on the brain. Therefore also was assumed direct neuroprotective effects. Here the growth factor BDNF (brain-derived neurotrophic factor) becomes a meaning, because he increases after exercise.
Has long been known BDNF promotes the survival of neurons in the hippocampus and in the cortex. That fact that high BDNF levels actually can reduce the risk of dementia, now investigated a study by US researchers from the Boston School of Medicine. In one of the oldest and best-known studies, the Framingham Heart Study, the scientists had found the content of BDNF in the blood more than in 2,100 participants aged over 60 years. Results were analyzed in the 1990s and researchers observed their health development in the next decade. The results showed that participants with low BDNF levels exposed to dementia more than others.
Brain-derived neurotrophic factor reduces risk of dementia.
The relationship was independent of other known risk factors such as hypertension, heart disease, smoking or diabetes. However, significant differences between high and low BDNF levels were recognizable only in women. In case of men, the difference in risk of dementia not significant and the Alzheimer risk did not exist. And there was a further restriction, because only in individuals over 80 years was found evident link between BDNF levels and risk of dementia .
Why is the growth factor in men and women affected so differently, is not entirely clear. The researchers, however, suspect interactions with sex hormones, which make women more vulnerable to reduction of BDNF levels. Relatively easy to explain why meaning of BDNF level is relevant only in participants over 80 years: Only then the serum levels significantly fall and show large differences between the subjects.
Other studies have shown that a higher BDNF levels are not sufficient to improve cognitive function. Obviously, that the brain must also be demanded, so that the degradation of nerve cells is counteracted. The most successful seems are the combination of sports and cognitive training.