LONDON, April 27 — It’s well established that exercise is good for our bodies, but what about our brains? A new American study, published in the Journal of Physiology, suggests that physical activity could play a key role in preserving our mental capacities, even when one of the brain’s key energy sources isn’t available.
This study focuses on a little-known mechanism: the production of ketones. These organic compounds are produced by the liver when the body is subjected to fasting, a low-carb diet or poorly controlled diabetes. Ketones then serve as an alternative energy source, particularly for the brain, when glucose is in short supply. Under normal circumstances, when glucose reserves are depleted, the liver takes over, generating these compounds that support essential brain functions such as memory and learning, while helping to maintain good brain health. But what happens if the liver becomes unable to perform this function?
This is precisely the question that researchers at the University of Missouri, Columbia, set out to answer. By artificially limiting ketone production in a number of volunteers, they observed a clear drop in cognitive performance. However, the subjects who took part in regular physical activity showed astonishing resilience: exercise seemed to overcome the metabolic impairment and restore, at least in part, memory and learning capacity.
Fuel for the brain
In other words, exercise alone could compensate for this metabolic deficit and enable the partial restoration of cognitive functions. “Going into the study, we thought that with fewer ketones and the cognitive impairments that causes, exercise may not be able to overcome that impairment. But it seems like exercise is so powerful that there are other mechanisms going on in the brain that allow it to circumvent those impairments and still receive the benefits from exercise,” explains Taylor Kelty, study coauthor and postdoctoral researcher at the University of Missouri, quoted in a news release.
This offers a promising avenue of exploration, particularly for people with liver disease, who are often unable to produce these ketones. This link between liver and brain, still largely unexplored, could well prove to be an essential pathway in the fight against cognitive decline, whether linked to age or certain pathologies. Indeed, research suggests that patients experiencing severe liver dysfunction are at greater risk of dementia.
Ultimately, the study highlights the importance of ketone production on brain health and the impact physical activity can have on staying mentally sharp. “This study highlights how exercise benefits the body in a multitude of ways, even when we don’t fully understand all the molecular mechanisms involved. Even when we remove a single pathway, exercise is doing so many other things that it can help mitigate those deficiencies,” says R. Scott Rector, a professor in the School of Medicine.
Exercise could be much more than just an ally for the heart and muscles. It could also prove to be a real booster for memory and mental alertness, paving the way for the consideration of physical activity as a key factor in brain health. — ETX Studio