Selenium is a chemical element, a nonmetal, which rarely occurs in its solid form, but is found in some form in meat, nuts (especially Brazil nuts), cereals and mushrooms. Scientists have been wondering for some time, how important dietary selenium actually is.
Now scientists at the University of Queensland say that it has the ability to reverse the cognitive impact of stroke and boost learning and memory in ageing brains.
Brazil nuts have the highest concentration of selenium in foods, but this mineral can also be found in meat, grains and other plants. Image credit: Quadell via Wikimedia (CC-BY AS 3.0)
Ageing is a huge topic in contemporary science. Researchers are still not sure what to consider it – a natural process or an illness. Can we solve ageing and should we? However, improving the life quality of ageing population is very important, because old age is currently associated with frailty as well as cognitive decline. Physical activity, as numerous studies have indicated, is one of the potential ways to preserve the ageing body and brain, but now scientists found that to some capacity dietary selenium supplements could replicate the effects of exercise.
Scientists tested dietary selenium and found that mice who get these supplements experience an increase in neuron production. Researchers could observe the reversal of age-associated cognitive deficits. As we (and mice) age the levels of new neuron generation decrease rapidly. Slowing this process down, halting or reversing it could improve cognition in elderly.
Furthermore, scientists tested whether selenium would have an impact on the cognitive decline sometimes experienced following stroke. For example, mice models of stroke could no longer perform some learning and memory tasks. However, after they received selenium supplements their ability returned to pre-stroke levels.
While these are hugely promising results, scientists warn against viewing selenium as a complete substitute for exercise. In fact, many people who have a balanced diet, already have enough selenium in their bodies. However, some older people could benefit from selenium supplements and that is an area of ageing definitely worth exploring.
Selenium is an essential mineral absorbed by plants from soil and water. Animals, such as cows and sheep, get their selenium through their food (grass, grains, etc.), which is why meat is rich in selenium. Too much selenium, of course, is not a good thing, but in normal conditions that would be hard to achieve by accident.
Older people often struggle to exercise. While selenium supplements are not going to solve that problem entirely, they could at least absorb some of that cognitive shock from the sedentary lifestyle. On the other hand, everyone could benefit from a memory capacity boost, especially older folks.
Source: University of Queensland