Is Stress Driving the Brain to Crave Comfort Food?

Chronic stress, combined with a high-calorie diet, can drive more and more food intake, thereby promoting weight gain and obesity.

stress overrode the brain’s natural response to satiety, leading to non-stop reward signals that promote eating more highly palatable food. The research was published in the journal Neuron
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From Stressed Brain to Weight Gain

While some people eat less during times of stress, most will eat more than usual and choose calorie-rich options high in sugar and fat.

To understand what drives these eating habits, the team investigated in mouse models how different areas in the brain responded to chronic stress under various diets.

How Does The Body React To Stress
Physical symptoms of stress on the body are varied, ranging from hormonal changes to changes in the nervous system, manifesting as the flight-fight-freeze response.

‘Stress is identified as an important regulator of eating habits that overrides the brain’s natural ability to balance energy needs.’

“We discovered that an area known as the lateral habenula, which is normally involved in switching off the brain’s reward response, was active in mice on a short-term, high-fat diet to protect the animal from overeating. However, when mice were chronically stressed, this part of the brain remained silent – allowing the reward signals to stay active and encourage feeding for pleasure, no longer responding to satiety regulatory signals,” explains first author Dr Kenny Chi Kin Ip from the Garvan Institute.

“We found that stressed mice on a high-fat diet gained twice as much weight as mice on the same diet that were not stressed.”

The researchers discovered that at the centre of the weight gain was the molecule NPY, which the brain produces naturally in response to stress. When the researchers blocked NPY from activating brain cells in the lateral habenula in stressed mice on a high-fat diet, the mice consumed less comfort food, resulting in less weight gain.

Driving Comfort Eating

The researchers next performed a ‘sucralose preference test’ – allowing mice to choose to drink either water or water that had been artificially sweetened.

Healthy Comfort Foods
Comfort foods can be based on habits or the unfamiliar; convenience or exploration. Healthy makeover for comfort food helps to de-stress and to celebrate joy.

“Stressed mice on a high-fat diet consumed three times more sucralose than mice that were on a high-fat diet alone, suggesting that stress not only activates more reward when eating but specifically drives a craving for sweet, palatable food,” says Professor Herzog.

“Crucially, we did not see this preference for sweetened water in stressed mice that were on a regular diet.”

Choice of Comfort Food Affected by Habits, Not Choice
When stressed, people seek out to eat foods which they don't really eat everyday, regardless of how healthy or unhealthy it is, a new study on 'stress eating' revealed

“In stressful situations it’s easy to use a lot of energy and the feeling of reward can calm you down – this is when a boost of energy through food is useful. But when experienced over long periods of time, stress appears to change the equation, driving eating that is bad for the body long term,” says Professor Herzog.

“This research emphasizes just how much stress can compromise a healthy energy metabolism,” says Professor Herzog. “It’s a reminder to avoid a stressful lifestyle, and crucially – if you are dealing with long-term stress – try to eat a healthy diet and lock away the junk food.”

Stress Relief by 'Comfort Foods' may Vary Between Sexes
Both men and women eat tasty foods as a strategy to reduce stress, and women may be more prone to this 'comfort food' style of eating.

Reference:

Critical role of lateral habenula circuits in the control of stress-induced palatable food consumption - (https://www.cell.com/neuron/fulltext/S0896-6273(23)00383-5)

Source-Eurekalert