If you find yourself reaching for a high-calorie snack in times of stress, your brain may be playing tricks on you, a study in mice suggests.
"Stress can override a natural brain response that diminishes the pleasure gained from eating, meaning the brain is continuously rewarded to eat," study leader Herbert Herzog, Visiting Scientist at the Garvan Institute of Medical Research in Sydney, Australia, said in a statement.
His team investigated how different areas in the brains of mice respond to chronic stress under various diets.
They found that the part of the brain normally involved in switching off the reward response - the lateral habenula - remained silent when the mice on a high-fat diet were stressed, keeping the reward signals active. As a result, mice that would ordinarily stop eating when full, continued to consume tasty high-fat foods, the researchers reported on Thursday in Neuron.
The researchers discovered that a neurotransmitter called NPY, which the brain produces naturally in response to stress, was causing the changes in the brain. When they blocked NPY from activating brain cells in stressed mice on a high-fat diet, the mice consumed less comfort food, resulting in less weight gain.
"Chronic stress, combined with a high-calorie diet, can drive more and more food intake as well as a preference for sweet, highly palatable food, thereby promoting weight gain and obesity," Herzog said. "This research highlights how crucial a healthy diet is during times of stress."
This newsletter was edited by Bill Berkrot. Additional reporting by Shawana Alleyne-Morris.
