A small trial found that older women who limited daily eating to about eight hours showed greater improvements in planning and problem-solving skills than those who ate over 12 hours. Both groups lost similar amounts of weight during the six-month study.
Researchers followed 47 women ages 50 to 79 with overweight or obesity. All participants reduced calorie intake by 500 calories per day. Twenty-six women also ate within a window of less than nine hours, typically from 10 a.m. to 6 p.m.
After six months, participants in both groups lost an average of about 15 pounds. The time-restricted group performed significantly better on tests of spatial planning and problem solving. They also tended to make fewer errors on memory and learning tasks, though that difference was not statistically significant.
"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 4 hours prior to going to sleep," said Sue Shapses, the study's principal investigator from Rutgers University.
The findings were presented on July 26 at the NUTRITION 2026 meeting in National Harbor, Maryland. Researchers noted that larger studies are needed to confirm the results.