Researchers in nutrition and neurology conducted a study in women over 50. According to them, meal times influence cognitive abilities such as memory, attention or organization.
What if our dinner time could influence our brain health? We already know that it is advisable to leave time between dinner and bedtime, because well-advanced digestion promotes better quality sleep. Dinner time could also determine the health of our liver. And according to preliminary work presented at NUTRITION 2026, the annual conference of the American Society for Nutrition, it could also affect the risk of dementia.
A team of researchers conducted a small study with 47 women aged 50 to 79, who were overweight or obese. The choice of this profile is not trivial: “women and people who are overweight or obese are at increased risk of developing (forms of dementia)”. Half of them (26) had to concentrate their meals on a window of less than 9 hours, generally between 10 a.m. and 6 p.m., while the others kept a usual window of around 12 hours. This “restricted window” diet consists of grouping all your meals over a short period of the day (here 8 to 9 hours), then fasting the rest of the time. The researchers’ idea was to check whether simply tightening meal times could protect brain functions.
According to the results, only participants limiting their eating window to 8 or 9 hours saw their cognitive performance improve. And researchers estimate that “there may be additional benefits to stopping eating 4 hours before bed”. For what ? The authors put forward several avenues: by respecting the circadian rhythm (the internal clock which synchronizes the body with day and night), we improve sleep, essential for cleaning brain waste and memory. Fasting phases would also promote the repair of neurons. Finally, by reducing inflammation and regulating blood sugar, this approach would limit two factors known to accelerate cognitive decline.
Concretely, what brain capacities are affected? This approach “had a modest effect on improving spatial planning and problem solving, as well as reducing errors related to memory and learning”explains Professor Sue Shapses, main author of the study, in a press release. Memory, attention and organizational capacity are therefore affected, cognitive pillars whose alteration is often the first sign of dementia. Notable fact: “The smaller the feeding window, the greater the improvements,” which suggests an encouraging proportional effect.
How to apply these principles on a daily basis? The important thing is to keep fixed meal times to give the body a regular rhythm. You just need to identify your usual bedtime and stop all food intake four hours before: to go to bed at 10 p.m., this means not eating anything after 6 p.m. The trick is then not to prolong the evening snacking and to postpone breakfast slightly. The authors point out, however, that “additional studies would be necessary to confirm these results with a larger number of participants”. In the meantime, dining earlier and tightening your meal times remains a simple, risk-free and easy-to-test habit.
