Recent research highlights that eating all meals within an eight-to-nine-hour window daily might offer brain health benefits beyond weight loss. This study, presented at NUTRITION 2026 by the American Society for Nutrition, explored the effects of meal timing on cognitive abilities.
The study’s key findings were clear. Participants who reduced their eating window showed improvements in cognitive functions after six months. Notably, both groups experienced similar weight loss, around 8%, but cognitive benefits were exclusive to those with time-restricted eating.
Sue Shapses, a professor at Rutgers University and the study’s primary investigator, emphasized the significance of the findings. “It is due to meal timing itself, because this was a randomized controlled trial,” she noted. However, she pointed out that results were limited to overweight or obese women losing weight, leaving unanswered questions for other demographics.
Alzheimer’s disease and dementia are increasing in prevalence with aging populations. Although diet and lifestyle have been linked to dementia risk, few studies have examined whether modifying these factors can reduce such risks. To address this gap, researchers involved 47 overweight or obese women aged 50 to 79 in a weight-loss program.
The participants were advised to reduce their daily intake by 500 calories. Twenty-six women followed a time-restricted eating schedule, limiting meals to fewer than nine hours daily, mostly between 10 a.m. and 6 p.m. This group had an average eating window of 8.2 hours. The rest maintained a traditional 12-hour eating schedule.
After six months, both groups lost about 15 pounds on average, indicating similar weight loss across groups wasn’t the differentiator. Cognitive test results revealed that those adhering to an eight or nine-hour window performed better in spatial planning and problem-solving. While memory and learning tasks improved, these changes weren’t statistically significant. Participants might therefore remember and process information more efficiently in daily activities.
Shapses noted that even minor reductions in the eating window linked to notable cognitive gains. She mentioned this method’s flexibility. “If they can’t do this every day – due to weekend events or weekday business dinners, occasional deviations are acceptable.” The study recognized deviations occurred among participants.
The team acknowledged the study’s small size and preliminary nature. Shapses concluded, “We will continue our analysis and submit the full-length manuscript for peer-reviewed publication.”
Reference: American Society for Nutrition. ‘Eating within 8 hours may help keep the aging brain sharp.’ ScienceDaily, 27 July 2026. www.sciencedaily.com/releases/2026/07/260727012125.htm