Scientists Say Eating Between These Hours May Benefit Brain Health

We all know that what you eat can affect your overall health—but new research suggests that when you eat might have an impact, too.

The study, which was presented at the American Society for Nutrition’s annual meeting, found that limiting food intake to a specific schedule might help keep your mind sharp as you age. The researchers enrolled 47 postmenopausal women classified as overweight or obese, and split them into two groups. The first group was asked to eat all food within a 12-hour window, which was meant to represent a typical eating pattern. The second group was asked to eat within a nine-hour window; participants in this group usually ate between 10 a.m. and 6 p.m., or within 8.2 hours. Both groups were asked to cut their daily calorie intake by 500 calories.

Participants also participated in a series of tests to measure their baseline intelligence, memory, learning, and reaction times, both at the start of the trial and after six months. By the end of the study, women in both groups lost an average of 15 pounds. But those who ate their food within the eight- to nine-hour window performed significantly better on tests designed to measure their problem-solving and spatial planning (the ability to visualize steps and outcomes before taking action).

Meet the experts: Clifford Segil, D.O., a neurologist at Providence Saint John’s Health Center; Keri Gans, R.D.N., dietitian and host of The Keri Report podcast; Sandra Zhang, R.D.N., L.D.N., registered dietitian nutritionist at the Frances Stern Nutrition Center at Tufts Medical Center; Davide Cappon, Ph.D., director of neuropsychology at Tufts Medical Center; Gitanjali Srivastava, M.D., medical director of the Obesity Medicine Enterprise at Vanderbilt Health

Those in the time-restricted eating group also made fewer mistakes on the memory and learning tests, but that data wasn’t statistically significant (i.e., it could have been due to chance). There was no difference between the groups in reaction time or multitasking.

It’s much too early to say whether everyone should try time-restricted eating, but the study’s results are definitely intriguing. Here’s what experts want you to keep in mind.

Why might this eating pattern help with cognition?

It’s important to flag that this was a pilot study—in other words, it was a trial run of sorts for a potential larger study. As such, more research is needed in this area before experts can draw any definitive conclusions. The researchers themselves also noted in the study that they’re not entirely sure why eating within a nine-hour window might boost cognition.

Still, there are a few theories. In the study, the researchers suggest that time-restricted eating may affect the body’s level of inflammation, or even how it responds to nutrients. Another possibility is that eating between 10 a.m. and 6 p.m. could align more closely with your circadian rhythm (your body’s internal clock). “We know that metabolism, blood sugar regulation, and sleep all follow a daily rhythm, and eating late into the evening may work against those processes, impacting cognitive function,” says Sandra Zhang, R.D.N., L.D.N., registered dietitian nutritionist at the Frances Stern Nutrition Center at Tufts Medical Center.

Davide Cappon, Ph.D., director of neuropsychology at Tufts Medical Center, believes there are likely multiple factors at work here. “A longer overnight break from eating may provide benefits beyond weight loss, possibly by improving metabolic health such as blood sugar control and better aligning metabolism with the body’s internal clock,” he says. “Together, these effects could help the brain work more efficiently.”

Add Prevention as a preferred source in your Google search results.

Use your Google account to add this to your settings.

Add to Google settings

Still, “this study did not prove any of those mechanisms,” says Keri Gans, R.D.N., dietitian and host of The Keri Report podcast. “Because this was a small pilot study and improvements were limited to certain thinking skills, more research is needed before drawing firm conclusions,” she adds.

Is there a diet experts recommend for brain health?

“To date, there is no dementia-protecting diet,” says Clifford Segil, D.O., a neurologist at Providence Saint John’s Health Center in Santa Monica, California.

However, experts will often urge those concerned about their cognitive health to maintain healthy habits. Dr. Segil suggests minimizing your added sugar intake, drinking plenty of water, and staying active; Gans recommends ensuring you get enough protein, fruits, vegetables, high-fiber carbohydrates, healthy fats, and fluids; Cappon says the Mediterranean diet is a good starting point. “More vegetables, berries, whole grains, beans, nuts, fish, and olive oil, and fewer highly processed foods and added sugars,” Cappon says.

Doctors will also often suggest the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet. Research presented at the American Society for Nutrition’s annual meeting in 2025 found that people who closely followed the MIND diet had a 12% to 13% lower risk of developing Alzheimer’s disease. The researchers also found that both older and younger adults benefited from the MIND diet, suggesting that people of all ages can see perks from the eating plan.

The MIND diet, which combines aspects of the Mediterranean and DASH diets, was developed as part of the Chicago Health and Aging Project study. It encourages followers to eat whole, minimally processed, plant-based foods common in the Mediterranean and DASH diets, like unrefined grains, legumes, vegetables, fruit, and nuts, according to the Academy of Nutrition and Dietetics. Followers are also encouraged to eat fish and poultry, while limiting saturated fats and added sugars.

Here’s a breakdown of the MIND diet’s recommendations:

• Two or more servings a day of vegetables, with at least one serving a day of leafy green vegetables
• At least two to five servings a week of berries
• Three or more servings a day of whole, minimally processed grains
• Five or more servings a week of nuts and seeds
• At least three to four servings a week of beans
• One or more servings a week of seafood
• Two or more servings a week of poultry
• Two tablespoons of extra-virgin olive oil a day

Should you try to alter your meal timing?

Maybe. Experts generally agree that more research is needed to understand the potential benefits of time-restricted eating. However, the perks of eating well before bed are already proven. “Finishing dinner three or four hours before bed is a change I’d recommend anyway,” says Gitanjali Srivastava, M.D., medical director of the Obesity Medicine Enterprise at Vanderbilt Health. “It’s good for blood sugar, reflux, and sleep. If it also protects the brain, that’s a bonus we’ll know more about in a few years.”

Zhang agrees. “I encourage people to eat consistently throughout the day and avoid heavy meals late at night,” she says. “Rather than focusing on a strict fasting window, I think it’s more important to align eating with waking hours and maintain regular meal patterns that support energy, appetite regulation, and overall diet quality.”