What is cortisol belly? Why stress could be making it harder to lose belly fat

What is cortisol belly?

When you're under prolonged stress, your body produces higher levels of cortisol - its primary stress hormone. Over time, elevated cortisol can influence your appetite, metabolism, and how your body stores fat, which may contribute to more fat around your middle.

While ‘cortisol belly’ isn't a medical diagnosis, it's a widely used term to describe this potential link between long-term stress and weight gain.

Helena Barham-Coppola, nutritional therapist and founder of Nourish&Be in London, notes that she sees this first-hand in her practice, with many clients unaware of just how stressed they are.

“If they have been operating on stress for as long as they can remember, that becomes their new normal, and they cannot pick up that they in fact are stressed,” she says.

Helena Barham-Coppola

How stress hormones affect belly fat

Long-term elevated cortisol levels can affect your blood sugar and insulin regulation. As well as contributing to weight gain around your stomach, they may also increase cravings for sugary foods and refined carbohydrates.

Barham-Coppola explains that when you're under stress, your hypothalamic-pituitary-adrenal (HPA) axis - the body's stress-response system - becomes activated, causing your cortisol levels to rise. This, in turn, raises your blood glucose levels, giving your body a quick burst of energy to prepare for the 'fight-or-flight' response.

“This rise then triggers insulin release to bring your blood sugar back to normal,” she says. “Insulin promotes fat storage, especially in the visceral area - specifically in a fatty layer that surrounds your organs, called the omentum.

“However, raised insulin can also lead to HPA activation and cortisol release - so they theoretically trigger each other.”

Barham-Coppola notes that when your insulin levels are high, it can make it harder for your body to release fat from visceral fat cells around the omentum. Put simply, higher cortisol levels can contribute to higher insulin levels, which may make it easier for fat to stay stored around your middle.

This means that even if someone eats a balanced diet and exercises regularly, they can still experience weight gain around their stomach, as stress and hormone balance can also play a role.

Why eating less isn't always the answer

Strict dieting combined with very intense exercise can elevate your cortisol levels. Over time, this stress response may encourage your body to conserve energy, increase muscle breakdown, and slow things down when it comes to your metabolism.

How stress can cause muscle loss

Barham-Coppola explains that one of cortisol’s key roles is to raise your blood glucose levels to help your body respond to a perceived threat. Even when your carbohydrate intake is very low - such as during a highly restrictive diet - your body still needs to maintain a supply of glucose. To achieve this, it can produce glucose from alternative sources, including the breakdown of muscle tissue.

“People often forget that exercise is in fact a stressor on the body,” she says. “When managed well, it can be a good form of stress. However, too much can lead to greater HPA axis activation and elevated cortisol levels.

“So if your body is under stress, whether from exercise or from general stress, and there are not enough carbohydrates to fuel the glucose rise, this can lead to muscle wasting as your body scavenges to make glucose out of anything it can - including muscle protein.”

How stress can slow your metabolism

Your muscles play an important role in supporting metabolic health, particularly in the context of insulin resistance. Barham-Coppola explains that muscle tissue is one of the few types of cells that can increase glucose uptake even when your insulin levels are low, with the support of gentle physical activity.

“This is why a nutritionist or doctor may recommend taking a walk after a meal to help regulate your blood sugar levels,” she says. “Resting metabolic rate (RMR) - the amount of energy the body uses at rest - is strongly associated with muscle mass, including in people living with overweight or obesity. This provides another important reason to prioritise building and maintaining muscle.”

Barham-Coppola explains that following a diet that significantly restricts calories can also cause your metabolism to adapt over time. When your cells detect that less energy is coming in, your body responds by conserving fuel, reducing the amount of energy it burns in a resting state.

This is one reason weight loss often reaches a plateau. As your body adapts, it becomes more efficient and starts burning fewer calories than it did at the beginning of the diet. This means the calorie deficit that was helping you lose weight gets smaller over time. Eventually, your weight may stop changing, even if you're still eating the same amount.

“I have seen it many times,” says Barham-Coppola. “Someone wants to lose weight so they restrict their dietary intake for prolonged periods, while maintaining an intense exercise routine. But your body is intelligent and senses this as scarcity, so it starts holding on to protect itself from what it perceives to be a famine.

“In fact, taking rest days and treat meals can remind your body that it is safe, and therefore can keep losing weight.”

Simple ways to lower stress and support weight loss

Certain types of exercise and eating habits can help calm your nervous system and lower cortisol without placing additional stress on your body.

Barham-Coppola recommends focusing on the following habits to help restore balance.

Exercise smarter, not harder

The goal is to lose weight without putting your body under unnecessary stress. Prioritise resistance training to build and maintain muscle, alongside gentle walking and flexibility-based exercise such as yoga. If you're already dealing with high stress levels, avoid relying solely on intense cardio sessions, which can further increase your stress response.

Plan ahead to avoid stress eating

Stress eating often happens when you're hungry and don't have a nourishing meal ready. Plan your meals a few days in advance, write a shopping list to match, and save it on your phone. That way, whatever life throws at you, you'll always have an emergency plan to help you make healthier choices.

Eat a Mediterranean-style diet

This is a well-balanced approach to healthy eating. Fill your plate with plenty of vegetables, oily fish, lean protein, olive oil, nuts and seeds, along with fruit and complex carbohydrates. Try to limit refined sugar and keep caffeine and alcohol in moderation, as they can all stimulate your body's stress response to some extent.

Prioritise your sleep

Poor sleep raises cortisol levels, making blood sugar harder to regulate and increasing appetite by disrupting the hormones that control hunger and fullness. Over time, inadequate sleep can have effects on your metabolism that are similar to long-term stress, making weight management more difficult.