During the course of the experiment when they drank their walnut smoothies, the people reported feeling less hungry.
When that mid-morning slump has you ready to pound that box of donuts, reach for some nuts instead: Eating walnuts can actually fight your cravings for junk food, a new study in Diabetes, Obesity, and Metabolismsuggests.
In the study, researchers recruited 10 obese adults for two, 5-day sessions: During one, the participants drank a smoothie containing 48 grams of walnuts each day. In the other, they drank a nut-free smoothie of comparable nutritional value.
During the course of the experiment when they drank their walnut smoothies, the people reported feeling less hungry. No surprise there—previous studies have found that walnuts are a key snack for satiety.
But then the researchers took it one step further: They performed MRI scans on the participants, and showed them pictures of desirable food like hamburgers and desserts. During the walnut-smoothie experiment, their scans showed increased activation in a part of the brain called the right insula, an area linked to cognitive control, regulating hunger, and cravings, compared to when they ate the regular smoothie.
This shows that they were paying closer attention to food choices, allowing them to select the healthier, less desirable options over the tempting junky ones, the researchers explained in a statement.
The researchers plan to test next if there’s an optimal walnut dosage—the amount they used in the study, 48 grams, equates to 314 calories—so they want to see if lesser amounts would still be effective, or if greater amounts would help even more. They also plan to look at how other compounds in food affect that part of the brain, which they believe can have important implications for treating obesity.
Now, the study was funded by the California Walnut Commission, so you may want to take it with a grain of salt. Still, there are many research-backed reasons to chow down on nuts, so it can’t hurt to incorporate them into your diet as a healthy fat source.