Older women who squeezed their meals into an 8 to 9 hour window each day scored measurably better on tests of spatial planning and problem-solving after six months than women who kept a standard 12 hour eating pattern.
Both groups lost about the same amount of weight, so the timing of the meals, not the size of the diet, appeared to explain the gap.
The finding comes from a Rutgers University pilot trial presented at NUTRITION 2026, the American Society for Nutrition's annual meeting held July 25 to 28 in National Harbor, Maryland.
The evidence is early. Only 47 women aged 50 to 79 with overweight or obesity took part, the study has not yet been peer-reviewed, and the cognitive gains showed up on some tests but not on others.
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Memory and learning scores trended in the same direction but did not reach statistical significance, and there was no measurable difference in multitasking or reaction time.
What the women in the study actually did
All participants were asked to cut 500 calories a day from their usual intake.
Twenty-six of them ate only between about 10 a.m. and 6 p.m., averaging 8.2 hours of daily eating. The other 21 kept a normal schedule and averaged 12.3 hours.
After six months, both groups had lost roughly 15 pounds, and the amount of weight lost did not differ between them. The difference emerged on cognitive testing.
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Lead researcher Sue Shapses, a professor at Rutgers University, said in a statement that "there was a modest effect of time-restricted eating to improve spatial planning and problem-solving and on reducing errors related to memory and learning."
Why timing may matter to the brain
Researchers suspect that eating within a narrower daytime window helps align food intake with the body's circadian rhythm, the roughly 24-hour cycle that governs sleep, hormone release and metabolism.
Shapses and her team plan to look more closely at how circadian rhythm, inflammation, nutrient-sensing pathways and metabolic health interact when meals are compressed into a shorter part of the day.
Independent commentary from Dr. Dung Trinh, chief medical officer of the Healthy Brain Clinic, echoed that framing.
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"The main takeaway is that when people eat may matter for cognitive health, not just how much they eat," Trinh told Medical News Today.
What this looks like in practice
The Rutgers protocol was straightforward. Meals happened between mid-morning and early evening, which meant no food for roughly four hours before bedtime.
Shapses put the practical rule that way herself. She said added benefit comes when a person can "stop eating 4 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."
Time-restricted eating has been studied for other outcomes too. A separate line of research has looked at whether limiting when you eat each day may quietly lower your blood pressure over time. The cognitive angle is newer and rests on much smaller trials.
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Anyone taking medications timed to meals, or living with diabetes, should talk to their doctor before shifting eating windows, because a schedule change can affect glucose control and drug absorption.
The Rutgers team says larger and longer trials are needed before an 8-hour window can be recommended specifically to protect the aging brain.
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This article is made and published by Jesper Bengtson, who may have used AI in the preparation.