Does our brain have an internal hunger switch? Researchers identify neurons that could “turn off” appetite

02/19/2020 / By Darnel Fernandez

Eating is a basic activity performed by all living organisms. Yet there is still much to learn about it, especially how and why eating becomes disordered. The National Eating Disorder Association reports that up to 30 million people in the U.S. suffer from an eating disorder, such as overeating, undereating, anorexia or bulimia. But despite eating being more commonly associated with the stomach, recent studies suggest that it is the brain that causes these disorders.

In a study published in the journal Nature Communications, researchers from the University of Arizona found a network of neurons in mice that work with other brain regions to influence eating behaviors and appetite. They believe that identifying its equivalent in the human brain and finding a way to control it can help people who suffer from disease-induced appetite loss or overeating.

Your appetite is all in your head

The goal of the researchers was to discover which part of the brain controls appetite and if it could be manipulated for the management of disease-induced eating disorders. They zeroed in on a group of neurons found in the amygdala or the brain’s emotional hub. The researchers referred to this group as a symphony conductor — a region of the brain that regulates appetite suppression and activation.

To determine whether or not these neurons control eating behavior, the researchers inhibited these neurons in laboratory mice using chemogenetic silencing. This resulted in increased food intake and total eating time. When the researchers reactivated these neurons, it triggered a decrease in appetite.

“By silencing the neurons within the circuit, we can effectively block feeding suppression caused by inflammation to make patients eat more,” said Haijiang Cai, one of the study authors. “We used anorexia for simplification, but for people with obesity, we can activate those neurons to help them eat less. That’s the potential impact of this kind of study.”

While everything about eating may sound simple, the researchers believe otherwise. They claim that the hunger people feel stems from the desire to satisfy nutritional deficits or get the reward of eating something delicious. Once a person finds food, he or she checks if it is good before chewing and swallowing. Satisfaction follows after a certain point.

Their findings led the researchers to believe that various parts of the brain coordinate with each other to control each step of the feeding process.

“This circuitry we found is really exciting because it suggests that many different parts of brain regions talk to each other,” Cai said. “We can hopefully find a way to understand how these different steps of feeding are coordinated.”

For the researchers, their next step is to identify the same neuronal network in humans and check if it works the same way. This will then allow them to develop a way to control feeding activities.

Keeping your appetite under control

Although the study shows that your brain is in command of your appetite, there are still some things that you can do to keep your appetite under control. (Related: Losing weight with appetite suppressing drugs, herbs and macronutrients.)

Eat more protein. Those looking to shed a few pounds can add a little protein to their diet. Eating more protein can increase your satiety. This will help you eat less and eventually lose weight.
Eat mindfully. In most cases, your brain understands when you’re hungry and when you’re full. However, eating too quickly or while you’re distracted can make it difficult for your brain to recognize these signals. Focusing on the food in front of you is key to practicing mindful eating. Not only will this help you appreciate your food more, it will also leave you feeling much more satisfied with what you ate.

Learn more about how your mind and body work to influence your activities at MindBodyScience.news.

Sources include:

Tagged Under: appetite, brain function, eating behavior, eating disorders, mind body science, mindful eating, neurons, overeating, protein, research, weight management