It’s been well-established that aerobic exercise improves brain health. But researchers haven’t been able to identify the specific pathways that make this possible.
But now researchers at the University of Queensland’s Brain Institute in Australia have identified a protein the body makes in response to exercise that kickstarts the creation of new neurons in the hippocampus, one of the brain’s most important memory centers.
However, to make that protein, the body needs access to a crucial nutrient. Let’s take a closer look at how this system – and this nutrient – can help your memory.
For at least twenty years, studies have shown that aerobic exercise like walking, running, swimming, biking, and similar activities can spur the growth of new neurons in the brain. Still, it was unclear what kind of compounds were being released into the bloodstream during and after exercise that might be triggering this process.
About seven years ago, Queensland researchers began laboratory tests analyzing blood samples from animals that were exercising to see which proteins might be involved. In those tests, they discovered 38 different proteins that significantly increased in response to exercise.
The one protein that particularly intrigued the researchers was selenoprotein P (SEPP1). It’s a protein that is responsible for conveying the mineral selenium to the brain and helps protect neurons from oxidative harm.
Most impressively, the level of SEPP1 in the blood doubled after the animals exercised.
New Neurons Doubled
In the most recent research, when the Australian scientists tested – in test tubes – how selenium affected cells that could form neurons, they found that the number of cells doubled in two weeks. And when they administered selenium into animals’ brains for a week, the number of cells that are precursors to neurons in the brain’s hippocampus tripled.1
In other tests, when older lab animals had selenium added to their drinking water for a month, the number of newly grown neurons in the hippocampus doubled.
Even more exciting, those new neurons helped the animals ace the memory tests that researchers gave them. In some cases, the animals could learn tasks twice as fast as animals who were not given selenium.
Plus, when the Australians tested selenium’s cognitive benefits on animals who had suffered brain injury they found it helped restore intellectual function. Function which had disappeared in the brain-injured animals not given selenium.
Long Term Improvement in Brain Health
Along with these Australian experiments, other studies have uncovered further potential brain benefits from selenium, including:
- Eating Brazil nuts, which are rich in selenium, may improve the thinking abilities of people with mild cognitive impairment (MCI): When researchers fed older adults who had MCI one Brazil nut daily for six months, they found that their verbal abilities and other mental capacities improved significantly. MCI is often a precursor to Alzheimer’s disease.2 In their published study, the researchers note that selenium reduces oxidative stress in the brain.
- Selenium compounds show promise for treating ALS (Lou Gehrig’s disease): Tests in England and Japan show that new chemicals made from selenium may help prevent toxic reactions in neurons that lead to ALS. The scientists believe “this is a significant step forward for developing a new class of drug candidates for ALS.”3
In my opinion, selenium is a mineral that’s vital for everyone and not only because of its importance to maintaining a sharp memory. Selenium can also help your body fight cancer along with a host of other health problems.
The Recommended Daily Allowance of selenium for adults is 55 micrograms daily—woefully low if you’re beyond middle age. Some studies have involved safely taking 100 micrograms daily while the upper daily limit limit is considered to be 400 micrograms. Selenium is toxic in large doses so be careful.
If you want to increase the amount of selenium using diet alone—the safest option– foods rich in selenium include Brazil nuts, tuna, sardines, beef, chicken, eggs, cottage cheese and brown rice.