Dementia and mental illness are not the most common subjects of Hollywood Blockbusters, but their have been some notable exceptions, for example the excellent performance of Bradley Cooper in Silver Linings Playbook depicting someone with Bipolar Disorder.
As a fitness professional and as someone who lost my father to dementia (I wrote in a previous blog, “Dementia: I lost my father, don’t lose yours” about my very personal experience with Alzheimer’s disease) the link between exercise and diet is one that really interests me.
Since my last blog on this topic then, there has been new evidence linking diet and exercise to the avoidance of dementia, an illness that is reaching epidemic proportions in our aging population.
A recent study by the University of California has concluded that high levels of “bad” cholesterol are linked to the presence of abnormal brain proteins that are seen in Alzheimer’s disease. Whereas previous studies have linked high cholesterol to Alzheimer’s, this is the first direct link between cholesterol levels in the blood to the concentration of amyloid plaques, the hallmark of this degenerative disease, in the brains of living patients.
The study reached the conclusion that whilst effects were small to moderate, over a prolonged period they can make a significant difference in reducing the prevalence of Alzheimer’s. Eating foods such as lentils, garlic, oily fish and avocados, and avoided saturated fats can help to lower “bad” cholesterol levels.
Another study reported in the US at the University of Pittsburgh concluded that physical exercise is as important in reducing the risk of dementia as keeping the mind active. By simply taking a brisk walk three of four times a week can effectively grow back the brain. The study involved 120 people aged 60 to 80. Half of the group had a brisk walk for 30 to 45 minutes three to four times a week. The other half only did light stretching exercises. After the 12 month test period, cognitive tests and MRI scans showed that the group who walked had a 2% growth of their hippocampus region of the brain, the part that is crucial for memory, and a similar growth in the pre-frontal cortex, the area involved in decision making and social behaviour. By contrast, the people in the other group showed a reduction in brain size which is in keeping with the “expected” rate of decline in the elderly.
It is not clear yet exactly how exercising can make the brain grow and improve brain function, but it is possible that the increase in blood flow improves the oxygen supply to the brain. Another possibility is that exercise encourages growth genes to trigger new connections between neurons.
Neural plasticity is a growing area of interest to science, and studies such as this one clearly show that the brain is able to grow well into old age, and that the “inevitable” decline in function is not as inevitable as was once thought.