Eating More of This Carbohydrate Could Reduce Your Dementia Risk, According to New Research

Pictured recipe: Creamy Spinach Orzo

What you eat can have a major influence on your brain health. That's why some eating patterns—like the MIND diet, which combines the Mediterranean diet and the DASH diet—focus on ingredients that can help keep your brain young. And while the foods that the MIND diet prioritizes are great ways to protect your brain, new research indicates that one nutritional priority in particular can have a big positive impact.

Consuming more dietary fiber, particularly soluble fiber, may reduce your risk of dementia, a study of more than 3,500 adults in Japan found. The study, published in Nutritional Neuroscience, used data from a survey that started in the 1980s. At the time, participants completed surveys assessing their dietary intake between 1985 and 1999. Most participants were between the ages of 40 and 64 when the study began, and they completed annual follow-up questionnaires from 1999 to 2020.

Based on the amount of fiber they consumed, participants were sorted into four groups, from most fiber consumed to least fiber consumed. Researchers found that the more fiber that participants ate, the lower their risk of developing dementia. Participants were even better off if they ate more soluble fiber, which you can find in foods like oatmeal, legumes and citrus. (Soluble fiber is the kind of fiber that makes you feel full and supports the bacteria in your gut, while insoluble fiber can support your bowel health.)

"Dementia is a devastating disease that usually requires long-term care," Kazumasa Yamagishi, M.D., Ph.D., a professor and lead author of the study, said in a media release. "We were interested in some recent research which suggested that dietary fiber may play a preventative role."

It makes sense that fiber could be a difference-maker when it comes to staving off dementia risk. Eating more fiber means the good bacteria in your gut can thrive, which can help reduce systemic inflammation. And research suggests that a healthy gut can protect your brain from Alzheimer's disease.

"The mechanisms are currently unknown but might involve the interactions that take place between the gut and the brain," Yamagishi said. "One possibility is that soluble fiber regulates the composition of gut bacteria. This composition may affect neuroinflammation, which plays a role in the onset of dementia. It's also possible that dietary fiber may reduce other risk factors for dementia, such as body weight, blood pressure, lipids and glucose levels."

The good news is that several of the foods recommended in the MIND diet, like whole grains, berries and legumes, are good sources of fiber. And eating more of this filling carbohydrate does more than just boost your brain health. It's also a good way to lose weight, since you'll feel fuller for a longer amount of time, and it's a bonus for your heart and bone health.

Bottom Line

Eating more dietary fiber, especially the soluble fiber found in oats, legumes and fruit, could help limit your dementia risk and support your gut health. To up your intake, try snacking on some high-fiber foods, like apples, raspberries and crispy chickpeas, or whip up high-fiber recipes like our Black Bean Hummus or Peppery Barbecue-Glazed Shrimp with Vegetables & Orzo.