New research is making the connection between high levels of the stress hormone cortisol and obesity. How chronic stress and cortisol can result in weight gain and excess fat has been known for many years. The study shows that people who are obese tend to be stressed out, and people who are stressed are more likely to become obese. The evidence reinforces how essential stress management can be to a successful weight loss program.
Measuring chronic stress
The main news from the study, conducted by researchers at University College London in the UK is the novel way they were able to measure chronic levels of cholesterol in 2,527 men and women aged 54 and older taking part in the English Longitudinal Study of Aging.
Previous techniques measured acute levels of cortisol in urine, saliva or blood. Instead, hair samples were analyzed, which allowed researchers to measure two months of cortisol accumulation. Among the findings, participants with higher levels of cortisol present in hair tended to have a higher body mass index (BMI) and a larger waist circumference. Those categorized as obese (BMI greater than 30, or a waist larger than 40 inches for men and 35 inches for women) had the highest levels of cortisol in their hair.
Cortisol and metabolism
Your adrenal glands, which ride on top of your kidneys, release cortisol during moments of excitement, fear, anxiety and exercise. This stress response, your “fight or flight” instinct, has a variety of effects on your metabolism. Cortisol constricts your blood vessels and teams up with epinephrine, another hormone produced by your adrenals, to accelerate your heart rate.
Cortisol also cues your liver to dump glucose into your blood stream for the energy you need to sprint away from an imminent threat. To keep your blood sugar levels high, cortisol also suppresses insulin production from your pancreas. Under normal conditions, when the threat subsides, your metabolism returns to normal.
A vicious cycle
You can see how chronic stress can result in high blood sugar, high blood pressure and a higher risk for diabetes and heart disease. How can chronically high cortisol levels make you fat? It’s a vicious cycle.
Cortisol can take fat from stores in your subcutaneous layer and move it to visceral fat cells in your abdomen. Cortisol also stimulates the development of more mature fat cells. What’s more, these visceral fat cells have more cortisol receptors than subcutaneous fat cells. Even worse, these visceral fat cells can start producing their own cortisol.
But cortisol isn’t done yet. Insulin allows glucose to enter a cell to be used for energy. The lack of insulin promoted by cortisol starves the cells in your body, even with all that fat stored in your belly. Powerful hunger signals are sent to the brain. Your body has been tricked into a desperate need for calories, which is often met by overeating, and unhealthy, high calorie, low nutrient food choices.
The first step to managing stress is to recognize the signs, such as anxiety, irritability and muscle tension. Try our some relaxation techniques such as deep breathing, yoga or meditation. Adjust your schedule to get more sleep. Before you eat, ask yourself why you’re eating. Are you really hungry, or are you stressed? When you’re temped to eat when you aren’t hungry, relieve your tension with some exercise.