August 4, 2026, 11:45 am | Read time: 3 minutes
Can the timing of meals make a difference for mental fitness in old age? A new study from the U.S. suggests that a limited eating window might not only aid in weight loss. The study showed a remarkable effect, particularly on cognitive and memory performance. When we eat could also impact whether we develop dementia in old age.
Study Examines the Link Between Meal Times and Brain Performance
Researchers at Rutgers University in New Jersey have found evidence that mental fitness and memory performance can be influenced by certain eating habits. The data were presented at the Nutrition 2026 conference in Maryland, as reported by “Medical Express.”1
For the pilot study, the scientists followed 47 overweight and obese women aged 50 to 79. All participants were instructed to reduce their daily calorie intake by 500 calories over six months. However, one group was allowed to consume their meals only within an eight- to nine-hour window, following the principle of intermittent fasting. Additionally, the last meal had to be consumed at least four hours before bedtime. The comparison group ate as usual, spread over about twelve hours daily.
There were hardly any differences in weight loss: Both groups lost an average of about seven kilograms. However, in various cognitive and memory tests, the women with the shorter eating window achieved better results.
Better Performance in Memory and Planning Tests
The differences were particularly pronounced in tasks involving spatial planning and problem-solving. The participants also made fewer errors in learning and memory tests. However, the researchers found no differences in reaction speed and multitasking abilities.
Study leader and nutritionist Prof. Sue Shapses explains: “Even weight loss alone can prevent some of the age-related cognitive decline. Our data suggest there could be additional benefits if one stops eating four hours before bedtime and limits food intake to eight to nine hours a day.”
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For Prof. Kleinschnitz, director of neurology at the University Hospital Essen, this is a small study whose results need to be confirmed in larger studies. Nevertheless, he sees the results as consistent with previous findings. He says: “Several studies have already shown that intermittent fasting could have a positive impact on the brain. Because eating is restricted to certain time windows, cells enter a mild hunger and alert state, triggering protective mechanisms in the cells.” According to the researchers, the effects could arise from the interplay of the biological clock, metabolic processes, and inflammatory responses.
Mild Cellular Stress as a Possible Protective Mechanism
Further research also points to the health benefits of earlier meal times. A review study showed that people who had their last meal before 7 p.m. had lower blood pressure, a smaller waist circumference, and better metabolic values.2
High blood pressure is considered one of the most significant risk factors for dementia, alongside obesity and twelve other factors.3 Prof. Kleinschnitz explains: “The body’s slight state of alertness can trigger processes that combat oxidative stress and inflammatory responses. This also seems to have a positive effect on brain cells.”
The neurologist also points to the significant role of body weight in the development of dementia. In Germany, more than 400,000 people are diagnosed with this condition each year.4 Experts believe that nearly half of all cases could be prevented or at least delayed with a healthier lifestyle. Prof. Kleinschnitz says: “Obesity is one of the biggest risk factors because it worsens cellular metabolism and contributes to inflammatory processes. Therefore, losing weight is an important factor in protecting against dementia.”