A recent study published in the journal Neuron highlights the connection between stress and a preference for unhealthy, high-calorie foods. Researchers have found that chronic stress can lead to a dependency on comfort foods, such as sweets and junk food, which can promote weight gain and obesity. The study, conducted on mice, showed that stress can override the natural brain response that diminishes the pleasure gained from eating, leading to a continuous desire for unhealthy foods over time.
The scientists focused on a part of the brain called the lateral habenula, which regulates the reward signals of food. In a control state, the lateral habenula prevented overconsumption of high-fat diets in mice. However, when the mice were chronically stressed, this brain region remained silent, allowing the reward signals to stay active and encourage feeding for pleasure, regardless of satiety regulatory signals. This led to stressed mice on a high-fat diet gaining twice as much weight as non-stressed mice on the same diet.
Furthermore, a molecule produced by the brain during stress called NPY was found to play a significant role in driving the preference for comfort foods. Blocking the production of NPY in test mice resulted in a decrease in the consumption of high-calorie foods and lesser weight gain. Another test using artificially sweetened water with sucralose revealed that stressed mice on a high-fat diet consumed three times more of the sweetened liquid compared to non-stressed mice on the same diet.
The results of the study suggest that stress not only activates more reward when eating but also specifically drives a craving for sweet, palatable foods. Nutrition experts recommend practicing mindful eating and savoring food to combat the long-term effects of stress on the body. Sitting down and focusing on the taste, smell, and feel of food, even for a few minutes, can help individuals better regulate their eating habits, particularly during times of stress.
Senior author Herbert Herzog of the Garvan Institute of Medical Research emphasized the importance of understanding the impact of stress on food consumption and weight gain. The study provides valuable insights into the mechanisms through which chronic stress can lead to an increased preference for unhealthy foods and subsequent weight gain. By identifying the specific brain regions and molecules involved in this process, researchers hope to develop interventions that target stress-induced food dependencies and promote healthier eating habits in individuals experiencing chronic stress.
