Eating Within Nine Hours Daily May Slow Dementia Risk, Study Finds

A pilot study of 47 older women shows that restricting meals to a nine-hour window may protect cognitive function better than calorie cutting alone. Both groups lost 7kg over six months on a 500-calorie daily deficit, but those eating between 10am and 6pm performed better on spatial planning and problem-solving tests. The findings, presented at the American Society for Nutrition conference on July 26, suggest meal timing may offer protection against cognitive decline.

What the study measured

Researchers at Rutgers University divided 47 women aged 50 to 79, all overweight or obese, into two groups. Both cut 500 calories daily for six months. The time-restricted group ate within an 8.2-hour window, typically 10am to 6pm, stopping food intake four hours before sleep. The control group ate over 12.3 hours. Both groups lost an average of 15 pounds. Cognitive tests showed the restricted group scored better on spatial planning and problem-solving, with hints of fewer errors on memory and learning tasks.

Why meal timing may matter

Professor Sue Shapses of Rutgers University noted that losing weight alone can slow cognitive decline, but timing offers additional benefits. The research team suspects circadian rhythms, metabolism, and inflammation play roles. Dementia is the leading cause of death in the UK and the seventh worldwide, killing nearly 2 million people annually. Experts believe nearly half of dementia cases could be prevented or delayed through lifestyle changes. Obesity in middle age raises dementia risk in later life by 30%.

How eating patterns differ in the West

In the UK, US, and other Western countries, people typically eat over a 14-hour period daily, leaving only 10 hours of overnight fasting. Research suggests extending overnight fasting can offer health benefits. A review published in January found eating before 7pm linked to improvements in body weight, BMI, waist circumference, and blood pressure. The findings suggest aligning nutrient intake with circadian rhythms may protect executive function and spatial memory in populations at elevated dementia risk.

What comes next

Professor Shapses described the cognitive effects as modest but meaningful. The research team plans to explore why meal timing influences cognitive health. The pilot study enrolled only women aged 50 to 79 with overweight or obesity, so larger trials across diverse populations are needed to confirm the results. The findings were presented at Nutrition 2026, the flagship annual meeting of the American Society for Nutrition, held July 25 to 28 in Maryland.

Final Thoughts

The pilot study suggests time-restricted eating may offer cognitive benefits beyond weight loss for older women at dementia risk. Larger trials are needed to confirm the findings. For UK readers concerned about dementia prevention, the data points to a simple lifestyle adjustment worth discussing with healthcare providers.

FAQs

Disclaimer:

The content shared by Meyka AI PTY LTD is solely for research and informational purposes.  Meyka is not a financial advisory service, and the information provided should not be considered investment or trading advice.