New research published in the journal Neuron has shown that chronic stress can override feelings of fullness, leading to overconsumption of food and cravings for sweets.
To see how stress affects the brain and eating, the authors used a mouse model. They fed mice a high-fat diet and then either left the mice to their usual habits or exposed them to chronic stress. After the experiment, the researchers examined the brains of the mice to see how the diet and chronic stress had changed areas of the mouse’s brains.
The authors found that when mice were chronically stressed and fed a high-fat diet, the part of the brain that switches off the reward response was not active, causing the mice to overeat. In other words, the mice continued to feel pleasure when eating due to an active reward signal, even after they should have been full and the signal should have been switched off. Mice on a high-fat diet who were not stressed showed activity in the area that switches off the reward response. Overall, mice on a high-fat diet who experienced chronic stress gained twice as much weight as mice on a high-fat diet who were not stressed.
In a second part of the experiment, the stressed and non-stressed mice were allowed to choose between regular water and water that had been sweetened with sucralose. The mice who were stressed consumed three times more sucralose water than the mice who were not stressed, suggesting that stress may drive cravings for sweet foods. Interestingly, stressed mice who were not fed a high-fat diet did not show a preference for sweetened water.
One of the authors noted that short-term stress can use a lot of energy, and high-calorie foods may be useful to regain energy and calm down. However, when stress becomes chronic, high-calorie foods are less useful and have a negative impact on the body. Stress, weight gain, and unhealthy diets are all linked to diminished heart health and worse overall health. To maintain optimal health, avoid chronic stress as much as possible, and be aware of the tendency to overeat and crave sweets when stressed.
Sources: Neuron, Science Daily
