A new study has found that reducing calories prevents loss of brain cells and slows down cognitive decline.
Calorie restriction is known to prevent aging and reducing the risk of mental conditions such as Alzheimer's disease. A diet that has fewer calories activates a key enzyme called Sirtuin 1 (SIRT1), which is associated with protection against loss of nerve cells. The study team even found a drug that activates the enzyme and helps the brain retain cognitive abilities.
The study was conducted by researchers from Picower Institute For Learning and Memory, Massachusetts Institute of Technology, and Howard Hughes Medical Institute. The study included a set of mice that were genetically tweaked to develop neurodegenertive diseases. Researchers kept these mice on a low-calorie diet and monitored the development of the disease. The mice were put on various mental tests after about three months.
"We not only observed a delay in the onset of neurodegeneration in the calorie-restricted mice, but the animals were spared the learning and memory deficits of mice that did not consume reduced-calorie diets," said Li-Huei Tsai, PhD, lead author of the study.
In the next part of the study, researchers gave a set of mice a drug that activated SIRT1. Test results showed that mice on the drug performed better at memory tasks when compared with mice that weren't on the drug.
"There has been great interest in finding compounds that mimic the benefits of caloric restriction that could be used to delay the onset of age-associated problems and/or diseases," said Luigi Puglielli, M.D., from the University of Wisconsin, Madison, who was not involved in this study, according to a news release. "If proven safe for humans, this study suggests such a drug could be used as a preventive tool to delay the onset of neurodegeneration associated with several diseases that affect the aging brain," Puglielli added.
Tsai added that although the study showed how activating an enzyme could lead to better cognitive function over time, the efficiency of this treatment is still unclear.