The Best Eating Habit To Prevent Dementia, New Study Finds

The foods that you eat can affect your life in so many ways. Not only do they help determine how much energy you have throughout the day, how your immune system functions, and even how well you sleep at night—they can also have a significant impact on your mind, either keeping you sharp or speeding up the cognitive decline process.

Now, new research suggests that sticking to a high-fiber diet could help protect you from dementia.

In the study, published in the journal Nutritional Neuroscience, researchers looked at more than 3,700 Japanese adults ages 40-64 over a period of about 20 years, give or take, estimating participants' dietary fiber consumption from self reports about what they had eaten in the previous 24 hours. The researchers noted that 670 cases of disabling dementia developed over the follow-up period, and those whose diets contained more fiber were less likely to develop the condition.

This inverse connection between fiber consumption and debilitating dementia was especially strong for soluble fiber. That is, eating more soluble fiber (instead of insoluble fiber) may be especially helpful at protecting you from dementia. For tips on knowing the difference between the two types and on choosing foods high in soluble fiber, learn about the Difference Between Soluble and Insoluble Fiber.

"It's a burgeoning area of research, that's for sure," Vicki Shanta Retelny, RDN, author of Total Body Diet For Dummies and host of the podcast Nourishing Notes, tells Eat This, Not That! in an interview. "In recent years, dietary fiber has been in the forefront as a powerful player in overall health, especially when it comes to cognitive health. Diversifying fiber-filled plant foods in the diet, such as fruits, vegetables, whole grains, pulses (beans, peas, and lentils), as well as nuts and seeds, has been shown to play a role in the health of the microbiome, which can affect brain health."

This particular study focused specifically on Japanese adults and did not test for causation—i.e., the fact that people who ate more fiber were less likely to get debilitating dementia was not necessarily because of the fiber, and there could be other factors at play. Still, it couldn't hurt to be sure you're getting enough fiber in your diet, since the nutrient can help with your digestion, your energy levels, your cholesterol, your skin and more.

"Aim to get a bevy of fiber-filled foods," suggested Retelny. "According to the Dietary Guidelines for Americans, the average adult should aim to get 14 grams of fiber per 1,000 calories, or 25-38 grams per day."

For more on how to make mind-healthy dietary choices, be sure to check out the 30 Best & Worst Foods for Your Brain.