For most people, dieting is a difficult endeavor. The feelings of hunger and frequent cravings associated with a caloric deficit are incredibly difficult to cope with. In a recent article we shared, we discussed a simple strategy that helps satiate those who are watching what they eat. A new study has now confirmed the validity of this strategy through brain imaging. Walnuts, it turns out, may be the key to helping people stick to calorie-restricted diets.
What makes fat loss so difficult
What makes fat loss so difficult is the fact that adipose tissue, or fat, does not sit idly. Fat has its own metabolism, gene expressions, and hormones that regulate how it is stored and burned. One hormone in particular, leptin, is a crucial part of satiation, or how full you feel, after a meal.
When you eat dietary fat, the digestion process releases leptin, which tells the brain when to feel full. Body fat also releases leptin. Therefore, body fat plays a role in satiation. The leptin from body fat sets a baseline that the brain gets used to (like a drug), and when body fat levels drop, the brain requires more leptin from dietary sources, i.e. food, to feel full.
In simpler terms, the more body fat you burn, the more food your brain will crave. It’s a failsafe system developed over thousands of years of famines to coax us to maintain stored fat and to replenish after a period of starvation. But in today’s world, it means this: people who try to lose weight are forced by their biology to overeat later, and this causes a cycle of weigh-loss/weight-gain.
Walnuts may help those trying to lose weight make better food choices
The new study released this month has demonstrated that walnuts may help those trying to lose weight make better food choices. What they found is that walnuts activate the area of the brain associated with the regulation of hunger and cravings. Explains lead study investigator Olivia Farr, Ph.D., ”We don’t often think about how what we eat impacts the activity in our brain. We know people report feeling fuller after eating walnuts, but it was pretty surprising to see evidence of activity changing in the brain related to food cues, and by extension what people were eating and how hungry they feel.”
Researchers have known from previous studies that walnuts do help people feel fuller on less food. Until now, however, the exact cause or effect within the brain was not well understood. Using fMRI images, researchers looked at the brains of two groups: those who had a diet with more walnuts (the “test group”), and those who had a diet with fewer walnuts (the “control group). They showed each group a set of images containing highly desirable “craving” foods, and watched their subjects’ brains light up. Only, the test subjects whose diet consisted of more walnuts didn’t light up as much.
Walnuts helps to suppress cravings and feelings of hunger
What the findings tell researchers is that eating walnuts helps to suppress cravings and feelings of hunger. This includes when people are exposed to strong visual cues. In the words of the study authors, “These findings suggest that walnut consumption may increase salience and cognitive control processing of highly desirable food cues, leading to the beneficial metabolic effects observed.” How walnuts accomplish this is by actually affecting the brain itself, specifically the part of the brain that deals with feelings of hunger and satiation.
If you want to control your eating more, both at meals and in between, consume a small serving of walnuts. Our primary caution remains. Walnuts are a fatty food, so make sure you only eat one serving a day, or thereabouts. Eating too many walnuts can quickly lead to weight gain. A good strategy is to spread the consumptions of walnuts across several meals, perhaps by adding a quarter serving to a salad, or adding a small amount to a shake. It’s up to you on how to eat your walnuts, if you choose to eat them at all.