I read an intriguing article recently published in the journal Ageing Research Review written by the Chief of the Laboratory of Neurosciences at the National Institute on Aging AND Professor at the Department of Neuroscience at the Johns Hopkins University School of Medicine. This amazing person is Dr Mark P. Mattson. The article was entitled “ Lifelong Brain Health is a Lifelong Challenge: From Evolutionary Principles to Empirical Evidence” (1).
This article describes the many lines of evidence indicating that regular exercise, energy restriction and intellectual enrichment sustain brain health and function during aging and may prevent neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases.
Dr Mattson believes that the brain is hardwired to function at a peak state when the individual feels hunger. Our human ancestors and wild animals had to survive by being able to locate and acquire food. Therefore, evolution selected for those members of a species that were able to outsmart and outrun their prey. This is in contrast to modern humans and domesticated animals where food is always easily available.
There is substantial evidence supporting Dr Mattson’s hypothesis from experiments performed with laboratory rats and mice. Typically mice and rats under laboratory conditions do not perform any exercise and eat as much as they like. When given running wheels, rats and mice will run up to 10 – 20 kilometers per day and mice that run show improved spatial learning and memory and increases in synaptic transmission and synapse number (a synapse is the junction between two nerve cells). Running also stimulates the growth of neural stem cells and increases the number of functional brain cells. Daily exercise can also prevent the decline in cognitive function that occurs with age in mice and rats.
Exercise can prevent the onset of disease in experimental models of Alzheimer’s disease, Parkinson’s disease and stroke in laboratory animals.
Dietary energy restriction has been shown to have similar effects on mice and rats, and the combination of exercise and energy restriction has been shown to have a greater impact on brain function than running or energy restriction alone.
Animal studies also suggest that intermittent exercise, fasting and intellectual enrichment can enhance recovery from traumatic brain injuries.
The article describes the mechanisms by which exercise, energy restriction and intellectual enrichment enhance cognitive performance during aging. I won’t go in to the details, but these mechanisms include the release of neurotrophic factors (proteins responsible for the growth and survival of developing neurons), activation of stress responses and signals received from other parts of the body, such as ketones from the liver.
Data from human studies suggest that people who exercise regularly during their adult life have a reduced risk of Alzheimer’s and Parkinson’s disease. To date there has been no studies looking at the impact of intermittent energy restriction on Alzheimer’s and/or Parkinson’s disease, however, there is evidence suggesting that overeating is a risk factor for both of these neurodegenerative disorders. Furthermore, intellectually challenging occupations and social engagement may also help prevent Alzheimer’s disease in later life.
Dr Mattson concludes with several points about the difficulties associated with conducting well-designed human trials involving vigorous daily exercise and intermittent fasting, which I agree with. These include the current eating patterns of three meals a day with snacks that we are all so accustomed to, the lack of physical activity required in most occupations, the over consumption of processed foods, which is heavily promoted and marketed by the food industry and the focus on disease treatment rather than prevention.
So what does this all mean to you? How can you use this information to prolong the life of your most valuable asset – your brain? Take Dr Mattson’s advice and ensure you are engaging in regular exercise, especially exercise that is mentally challenging and vigorous. For example, don’t just go for a long, slow walk. Instead choose a route with hills and sprint up the hills then recover on the way down.
What about intermittent fasting? Fasting may sound daunting to some people but I have incorporated this into my life by skipping lunch during the week. While I am busy and occupied at work I do not feel the need to eat lunch and have learnt to suppress my feelings of hunger. This becomes easier the more you do it and I am now completely comfortable with this experience.
And perhaps watching television in the evenings is not the most intellectually challenging pastime to be engaging in. Why not read a great book instead?
Try incorporating daily exercise, bouts of food deprivation and intellectually stimulating activities into your life to enhance the lifelong health of your brain.
- Mattson, M. P. (2015). Lifelong Brain Health is a Lifelong Challenge: From Evolutionary Principles to Empirical Evidence. Ageing Res Rev. 20: 37-45.