Calorie Restriction & Brain Health: Study Findings

Milan, 26 Nov. (Adnkronos Health) – Calorie restriction again under the lens of science. The approach that involves reducing the total intake that is introduced daily with the diet is explored by a team of researchers in terms of protection for the brain, compared to the harmful changes that can arise with age. From the new study, signed by experts from the Boston University Chobanian & Avedisian School of Medicine, it emerges that consuming 30% fewer calories than usual for more than 20 years could slow down brain aging. As time progresses, the authors explain, the cells of the central nervous system undergo metabolic dysfunction and an increase in oxidative damage. These cellular problems risk compromising the ability to preserve the myelin sheath (the protective covering that surrounds nerve fibers), leading to age-related white matter degradation. Microglia are the main immune cells of the brain and their activation is a normal response to injury or infection. In conditions such as aging or Alzheimer’s, microglia can become chronically activated, leading to a harmful inflammatory state that impacts neurons, but the exact reasons for this process are not yet fully understood. The study by US researchers was conducted using an experimental model closely related to humans. “Although calorie restriction is a well-established intervention that can slow biological aging and reduce age-related metabolic alterations in short-term experimental models,” the work just published in Aging Cell “provides rare long-term evidence that calorie restriction can also protect against brain aging in more complex species,” explains corresponding author Ana Vitantonio, a fifth-year Ph.D. student in the Department of Pharmacology, Physiology and Biophysics. The research is based on a study started in the 1980s in collaboration with the National Institute on Aging involving 2 groups: one followed a normal and balanced diet, while the other ate approximately 30% fewer calories. The original goal was to determine whether reduced calorie intake could extend lifespan. The participants lived their natural lives and their brains were analyzed post-mortem. The researchers used a technique known as single-nucleus RNA sequencing, which allowed them to evaluate the molecular profile of individual brain cells. They compared the brain cells of those following a normal diet with those of people on a low-calorie diet, which allowed them to observe how a reduced calorie intake affected the expression of genes and the activity of aging-related pathways in brain cells. Brain cells subjected to calorie restriction were found to be metabolically healthier and more functional, exhibiting increased expression of myelin-related genes and enhanced activity in key metabolic pathways that are crucial for the production and maintenance of myelin. According to the authors, these findings support the idea that long-term dietary interventions can influence the trajectory of brain aging at the cellular level. “This is important because these cellular alterations could have relevant implications for cognition and learning,” remarks Tara L. Moore, Ph.D., professor of anatomy and neurobiology. “In other words, dietary habits can influence brain health, and reduced calorie intake can slow some aspects of brain aging if implemented long-term.”