Why do we crave unhealthy food? Scientists discovered a process that leads to snacking

We know that certain types of foods are bad for us. And at the same time quite often we crave for high-calorie food like it is our only way to survive. Now scientists from the University of Waterloo in Canada have determined that it might have something to do with our brain. Suppression of the dorsolateral prefrontal cortex e brain region, responsible for self-control, leads to craving of unhealthy food.

We kind of know that when we lose control, we want to eat. And not just food – we are craving something super unhealthy. Scientists decided to see what is happening in our brain during such moments and so they used a technique called transcranial magnetic stimulation to temporarily suppress the dorsolateral prefrontal cortex of some participants. This bizarre technique is actually perfectly harmless, but allows seeing how human behaviour changes in such situations. And scientists found that started paying more attention to appealing images of high-calorie snacks. They found them more attractive and immediately wanted to eat this kind of food.

Of course, sometimes we all crave some foods and transcranial magnetic stimulation is not needed for that. But in this case participants reported that their urges to eat unhealthy foods were way higher than usual. Furthermore, scientists chose 28 young adult females for this study – all of them had frequent cravings for high-calorie foods, but were healthy. Scientists even used a placebo simulation on a control group and found that 89 % of participants consumed more high-calorie food after real simulation than after a placebo simulation. But of course, in real life, when we are craving some food, no one is stimulating our brain and measuring its activity. So what is happening?

Our brain is always stimulated by the things we do and transcranial magnetic stimulation is just a controlled way to replicate that in a lab. Cassandra Lowe, lead author of the study, explained: “Several lifestyle factors affect the function of the dorsolateral prefrontal cortex. For example, aerobic exercise has been shown to enhance it, while lack of sleep and stress can impair it – so there may be a link between these lifestyle factors and overeating via their impacts on the brain”. In other words, if you will exercise, you will reduce your cravings. And if you are under stress a lot or do not sleep well enough, you may experience stronger cravings for high-calorie food.

So it all comes back to your lifestyle. While occasional instances may not do you too much harm, frequent snacking is bad for you. However, even if you feel like you need an unhealthy snack, you really don’t – eat some fruit.

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