A daily dose of walnuts may act as a prebiotic by increasing the levels of good bacteria in your gut, according to recent research conducted on rats published in the Journal of Nutritional Biology. This affects your gut in a positive way, increasing bacterial diversity and lowering the risk of obesity. Lead study author Lauri Byerley, PhD, of the LSU Health New Orleans School of Medicine notes that the gut microbiome is a new area of study. Her team aren’t certain if it’s the levels of specific bacteria in the gut or the gut’s overall bacterial diversity that is most important for improved health, but these results are still encouraging. There’s further indication that walnuts should take center stage in more of your meals: Additional research from Human Nutrition Unit at Beth Israel Deaconess Medical Center found that when study subjects drank a shake containing 48 grams of walnuts (the serving recommended by the American Diabetes Association) they reported feeling fuller than when they consumed a similarly flavored drink that was nutritionally comparable. Their level of satiety was also confirmed with the use of brain scans after consuming the walnut shake. No matter how good this news may be, always watch your portion sizes and practice moderation. “Eating one particular food every day does not overcome a bad diet and prevent chronic diseases,” notes Byerley, adding that the rats in her study ate two daily servings of walnuts but were also supplied with all of the other nutrients they required.