A new study suggests that when people eat may be just as important as what they eat when it comes to protecting brain health.
Researchers found that older women who limited their meals to an eight- or nine-hour window each day showed modest improvements in memory, problem-solving, and planning skills compared with women who ate over a more typical 12-hour period. The findings were presented this week at NUTRITION 2026, the annual meeting of the American Society for Nutrition.
While the results are encouraging, researchers caution that the study was small and does not prove that time-restricted eating prevents dementia. Larger studies will be needed to confirm the findings.
Study Examined Meal Timing and Cognitive Health
The six-month clinical trial included 47 women between the ages of 50 and 79 who were overweight or obese, both factors associated with an increased risk of cognitive decline and dementia.
All participants were instructed to reduce their daily calorie intake by 500 calories as part of a weight-loss program. However, 26 women were also asked to consume all of their meals within an eating window of less than nine hours per day, typically between 10 a.m. and 6 p.m. The remaining participants continued eating over an average period of about 12 hours each day.
By the end of the six-month study, both groups had lost roughly the same amount of weight — about 15 pounds on average.
Despite similar weight loss, researchers found important differences in cognitive performance.
Time-Restricted Eating Linked to Better Thinking Skills
Women who followed the eight- to nine-hour eating schedule performed significantly better on tests measuring spatial planning and problem-solving than those who maintained a longer eating window.
Researchers also found that participants in the time-restricted eating group tended to make fewer mistakes on tests involving memory and learning, although those improvements did not reach statistical significance. No meaningful differences were found between the groups on tests measuring reaction time or multitasking.
“These outcomes suggest a better ability to remember information during everyday tasks and reducing mistakes related to memory, attention and problem-solving,” said principal investigator Dr. Sue Shapses, a professor at Rutgers University and Rutgers Robert Wood Johnson Medical School, Science Daily reported. “Reductions in the eating window predicted greater improvements.”
Weight Loss Alone May Not Explain the Benefits
Because both groups lost nearly identical amounts of weight, researchers believe the timing of food intake may have contributed to the improved cognitive performance.
“Losing weight alone will ward off some of the aging-related cognitive decline, and these data suggest that there may be additional benefits if you stop eating four hours prior to going to sleep and reduce food intake to 8-9 hours per day, compared to the usual eating window of 12 hours per day,” Shapses said.
Researchers believe the benefits could be related to several biological processes, including improved circadian rhythm, reduced inflammation, better metabolic health and changes in nutrient-sensing pathways.
Dementia Cases Continue To Rise
The researchers noted that Alzheimer’s disease and other forms of dementia are becoming increasingly common as the population ages. Women and people who are overweight or obese face a higher risk of developing these conditions.
Although previous research has linked healthy diets and lifestyle habits to better brain health, relatively few clinical trials have examined whether changing eating schedules alone can reduce dementia risk.
More Research Needed
Researchers emphasized that the findings should be interpreted cautiously because of the study’s small size and limited participant population.
Future studies will evaluate whether similar cognitive benefits occur in larger and more diverse groups of people and will explore the biological mechanisms that may explain why limiting daily eating hours could help support brain health.
For now, the findings suggest that pairing weight loss with an earlier, shorter eating window may offer additional cognitive benefits, but experts say more evidence is needed before recommending time-restricted eating specifically as a strategy to reduce dementia risk.
Provided by Dallas Express
