© Debby Lewis-Harrison / GettyWalnuts could help fight food cravings, study shows
Everyone experiences cravings from time to time, and such strong urges can often be the downfall of even the most strong-willed dieter. But it turns out that there is one simple kitchen staple that could keep those hankerings at bay, proving a valuable weapon for people wanting to lose weight.
Researchers at Beth Israel Deaconess Medical Centre (BIDMC) have found that walnuts can activate the area of the brain linked to controlling hunger and cravings. Although the health benefits of nuts are widely known, this is the first time experts have analysed the way in which they can change your brain. So, how does it work?
The experiments involved two different 5-day sessions, during which 10 people - all of whom were classified as obese - were asked to drink two different smoothies. The first smoothie was made using 48 grams of walnuts, while the second did not contain any.
On the final day all participants were asked to go through a functional magnetic resonance imaging (fMRI) test, during which they were shown 'food porn' images of high-fat foods - such as hamburgers and desserts - followed by less craving-inducing items like vegetables. Although, unsurprisingly, people reacted more to images of unhealthy foods, it was also found that the right insula area of the brain (responsible got control) became more active in those who drank the walnut smoothies when they viewed the images of unhealthy but delicious food. Study lead Christos Mantzoros, director of the Human Nutrition Unit BIDMC and professor of medicine at Harvard Medical School, said: "We know there's no ambiguity in terms of study results. When participants eat walnuts, this part of their brain lights up, and we know that's connected with what they are telling us about feeling less hungry or more full."
Indeed, as in previous observational studies, those who consumed the walnut smoothies reported feeling less hungry during the week than those who were drinking the placebo smoothies. Mantzoros added: "From a strategic point of view, we now have a good tool to look into people's brains - and we have a biological read out. We plan to use it to understand why people respond differently to food in the environment and, ultimately, to develop new medications to make it easier for people to keep their weight down."
The extremely small sample size means that more large-scale tests need to be done before research can move forward, but it is hoped that the scientists can replicate the apparent effects of walnuts using other varieties of nuts.
Walnuts have previously proven beneficial at fighting inflammation, lowering cholesterol and improving bone health.
The study was published in the journal Diabetes, Obesity and Metabolism.