The correlation between dietary habits and chronic stress: How does stress affect the feeling of hunger?

Unhealthy dietary habits and excessive body mass are among the leading health problems of the modern way of life. Obesity is a proven risk factor for developing cardiovascular diseases, diabetes mellitus type 2, osteoarthritis, and certain types of cancer. At the same time, the number of chronically stressed people is rising. Since our appetite is heavily affected by stress, the way we cope with stress plays a significant role in maintaining a healthy body mass and lowers the risk of chronic illness.

Acute stress: decreased appetite and activation of the “fight or flight” mechanism

Short-term stress usually results in reduced appetite. The sympathetic nervous system is activated, stimulating the adrenal gland to secrete adrenaline. Adrenalin prepares the body to deal with stress, increases energy consumption, and slows the digestive tract. This evolution acquired mechanisms that redirect energy from digestive processes to survival functions. After the stressful situation is over, the secretion of cortisol, a hormone that stimulates regeneration and energy compensation, rises.

Chronic stress: long-term high cortisol and increased food intake

Contrary to acute stress, chronic stress leads to permanently high cholesterol levels. Increased appetite can lead to food intake that exceeds the body’s actual energy needs.  Elevated cortisol also promotes the accumulation of fat cells, particularly in the abdominal region, and increases the desire for high-calorie, fatty, and sweet foods. This combination makes chronic stress a significant factor in the development of obesity.

The role of ghrelin and insulin in stress overeating

Chronic stress also influences the food we consume. The research shows that stress is linked to increased intake of high-calorie foods rich in saturated fats and simple carbohydrates. One possible explanation is the simultaneous action of elevated cortisol and insulin, while others believe that ghrelin is the cause.

Ghrelin, the hunger hormone, is also increased during chronic stress. Its elevated levels stimulate appetite and may contribute to the accumulation of fat. Insulin, the hormone that regulates blood glucose levels, in chronically elevated conditions, additionally stimulates energy storage in the form of fat. People who are overweight often have hyperinsulinemia, which further complicates appetite control.

The brain under stress: elevated desire for “comfort food” and reduced feeling of satiety

At the same time, stress increases the activity of the limbic system– a region of the brain responsible for emotions, reward, and habits- while decreasing the activity of the prefrontal cortex, responsible for impulse control and rational decision making. The combination of increased cravings and reduced self-control makes chronic stress a strong risk factor for obesity.

Animal studies show that stress may lower the activation of a part of the brain called the lateral habenula. When its activity is lowered, the brain does not recognize satiety signals as well and increases cravings for high-calorie foods.

How to manage stress and ease appetite regulation?

Excessive consumption of unhealthy foods is just one of the ways that stress negatively affects our health. People who are chronically stressed often have poor sleep quality, are less physically active, and often reach for alcohol, all of which can further contribute to excessive body weight.

Finding healthy ways in which we cope with chronic stress is also a way we can tackle the problem of obesity. Prioritizing sleep, meditating, regular physical activity, educating ourselves about healthy dietary habits, and sharing out experiences with friends and family can help to reduce the feeling of stress, which can help maintain a healthy body weight and thus better mental and physical health.

Translated by: Mirta Maršić