Although neurogenesis inevitably slows as we get older, scientists are discovering that growing new brain cells can be stimulated in adults by adjusting lifestyle and diet.
Neuroscientist Sandrine Thuret has been delving into a fascinating area of the brain, the hippocampus, associated with memory, learning, mood, as well as spatial navigation. What they have found is that, when everything is working well, this can be a site of intensive neurogenesis in adults. When the ability of the hippocampus to generate new neurons is blocked, we experience a deterioration of memory and this affects our ability to recover from depression and other mental health problems.
The decline in memory and learning ability that we experienced as we age, is similar to what happens when we are stressed. In addition to stress and aging, other factors affecting the ability of the hippocampus to generate new brain cells are: sleep deficiency, alcohol, a diet high in saturated fats and sugar, and vitamin A and B deficiency. These factors combine to result in a dramatic decline in neurogenesis.
But recently Thuret has discovered that the hippocampus is a unique area of the brain (actually, one of two, the other being the lateral ventricals) in which adults can continue to grow new neurons into old age with the right combination of physical and mental activity and diet.
It isn’t news that a well-balanced diet combined with exercise is beneficial for a longer life, healthy organs and reducing the risk of cancers, but it’s now emerging that these factors, especially diet, can have a profound effect on mental health as well.
Thuret has worked with an oncologist colleague to study patients who were recently cured of cancer, but were surprisingly struggling to overcome depression in spite of the good news. They discovered that the cancer-fighting drugs had reduced the production of new brain cells in the hippocampus. This is important because neurogenesis helps us overcome depression, literally regrowing our brains and giving us the ability to form new memories and learn new mental patterns.
Thuret has identified specific factors that can stimulate hippocampal neurogenesis and therefore improve mood and cognition. These include strenuous exercise (for example running), sex, learning something new. She also emphasises a diet high in omega-3 fats, resveratrol, curcumin, vitamins A, E and B, folic acid, zinc and flavonoids. Thuret mentions a few foods that are high in some of these essential nutrients, such as blueberries, dark chocolate and salmon.
A combination of Res-V, Lester’s Oil and Multiva from About Health covers most of the ingredients mentioned by Thuret that enhance neurogenesis.
• Res-V Ultimate contains high concentrations of resveratrol and curcumin
• Lester’s Oil contains a high dose of the essential omega-3 fatty acids combined with powerful antioxidants
• Multiva contains vitamins A and B, zinc, folic acid, flavonoids, as well as a host of other essential vitamins and minerals that we don’t necessarily get enough of in our diets, such as selenium, which is particularly important for New Zealanders, as it is not present in our soil.
Another surprising find was that eating textured foods, especially crunchy or tough food that requires chewing, stimulates hippocampal neurogenesis, and that intermittent fasting (spacing the time between meals) is also beneficial.