Stress reduces a person's immunity and can create serious long-term health issues such as high blood pressure, heart disease, obesity and diabetes. Studies have shown that stress affects a person's eating habits. Some people eat more and crave comfort food during periods of stress, anger, fear, boredom or sadness, often termed emotional eating.

The latest study explains how the brain signals during stress cause over-indulgence in comfort food.

During periods of stress, signals in the brain's lateral habenula that indicate satiation turns off, which would have otherwise let the person know they have eaten enough.

When the brain signals malfunction, people tend to eat more, and most often indulge in comfort food that is high in fats, leading to weight gain and obesity. The findings of the study were published in the journal Neuron.

"Our findings reveal stress can override a natural brain response that diminishes the pleasure gained from eating – meaning the brain is continuously rewarded to eat," said Herbert Herzog, senior author of the study.

Researchers made the findings after evaluating chronically stressed mice. The brain signals in the lateral habenula of the brain were inactive while they ate high-fat foods, which made them eat more without becoming satiated.

"We discovered that the lateral habenula 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," first author Kenny Chi Kin Ip said.

Stress also induces a craving for sweet food. The study showed that stressed mice consumed three times more sucralose than others. They produced a molecule called NPY, which was responsible for weight gain. When NPY was blocked from activating brain cells in the lateral habenula of stressed mice, they consumed less comfort food, resulting in less weight gain.

"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," Ip added.

Tips to prevent emotional eating

  • Manage stress with techniques such as yoga, meditation or deep breathing
  • Keep a food diary to track when and what you eat
  • Keep yourself distracted to avoid eating while you are bored
  • Check if your hunger is real or if it is just a craving
  • If you feel like eating something between meals, indulge in a healthy snack, such as fresh fruit or vegetable
Eating woman
Researchers discovered how the brain signals during stress cause over-indulgence in comfort food. Pixabay