Cortisol and gaining weight

If you have ever wondered why, despite a healthy diet and regular training, you still can’t lose weight or even happen to gain extra kilos, analyze whether the main culprit isn’t stress, or more precisely, long-term elevation of cortisol in your blood, which can lead to hypercortisolemia.

The heavy burden of stressors related to the modern lifestyle and the fact that in many cases this exposure is chronic show that it is the personality type and the individual way of coping with stress in personal and professional life that may contribute to the development of chronic hypercortisolemia at the tissue level. This, in turn, will predispose you to develop some features of the metabolic syndrome and, more rarely, to develop Cushing's syndrome or disease.

What is cortisol?

Cortisol is a natural steroid hormone that is made from cholesterol by the zona fasciculata of the adrenal cortex. It is one of the main representatives of glucocorticosteroids, i.e. compounds that affect blood glucose levels. It is often referred to as the “stress hormone” and, moreover, has a great influence on metabolism. It is characterized by the circadian rhythm of secretion, where the highest concentration occurs in the morning hours (150-700 nmol/l at 8 a.m.), and the lowest in the late evening hours (30-12 nmol/l at midnight).

Normally, cortisol is released in response to certain daily events and circumstances, such as waking up in the morning, exercise or severe stress. The action of cortisol has a very long range, and the effects of its excess are extremely harmful to your body, and weight gain is one of the more troublesome problems that this hormone can cause.

What does cortisol affect?

Cortisol affects a number of processes in the body, the most important of which are:

• increasing the synthesis of glucose in the blood in response to stress, as well as during physical activity, i.e. in situations where the body’s need for energy increases,
• immunosuppressive and anti-inflammatory effects, showing that it is necessary for the proper functioning of the immune system,
• increase in heart rate, leading to an increase in blood pressure,
• enhancing the action of other “stress hormones” (adrenaline and norepinephrine), and thus enabling better stress management,
• regulating the strength of connective tissues,
• the intensity of protein breakdown,
• intensification of the breakdown of triglycerides,
• increasing the secretion of gastric juices,
• participation in the proper development of a fetus,
• sodium retention in the body,
• increasing potassium excretion,
• contributing to the release of calcium from bones.

What does cortisol have to do with gaining weight?

The level of stress that accompanies you every day has an extremely significant impact on your weight. Sometimes it causes its loss, and other times it contributes to the deposition of adipose tissue. This is due to your body’s response to cortisol, which is closely related to metabolism, insulin and glucose levels, and the accumulation of body fat.

Stressful experiences and trauma such as loss of a loved one, divorce, accident, financial crisis, exam or chronic stress can lead first to long-term blood cortisol levels, then to excess weight, and then to obesity. This is because elevated blood cortisol levels lead to increased appetite, including frequent and uncontrolled cravings for snacks rich in sugar and fat.

How does cortisol work?

Stress induces a “fight-or-flight” response in your body. This response releases hormones like adrenaline and cortisol. Adrenaline prepares the body to go into action and reduces appetite. Once the adrenaline has worn off, cortisol comes into play, inducing a persistent appetite for sweets. This is because blood glucose levels rise, fueling the fight or flight response to avoid hypoglycemia. In addition, there is an increase in blood pressure aimed at better blood supply to internal organs.

Additionally, cortisol contributes to the temporary inhibition of functions that aren’t necessary for you in a given situation, such as digestion, immunity, reproduction. This, in turn, is a fatal connection with the fact that under the influence of a stress stimulus, eating food activates the so-called “reward pathway” that can cause chronic overeating.

High levels of cortisol can also hinder wound healing and cause memory and learning problems as it is toxic to brain cells, damaging the hippocampus.

How does cortisol cause weight gain?

The effect of a long-lasting elevated level of cortisol on the process of fat deposition works on three different levels:

Build up of visceral-abdominal fat

First, by accumulating abdominal fat, also known as central, visceral, or android obesity. Cortisol can mobilize triglycerides, obtained from adipose tissue stores, and transfer them to visceral fat cells. Central adipose tissue fat cells contain more cortisol than subcutaneous fat. Scientific research proves that there is a strong relationship between the visceral type of fat accumulation and diseases such as ischemic heart disease, type 2 diabetes, and arterial hypertension.

In addition, cortisol enables the development of adipocytes (fat cells) into mature fat cells. This biochemical process at the cellular level is mediated by the enzyme dehydrogenase 11β-hydroxysteroid type 1 (11b-HSD1), which converts cortisone to cortisol in adipose tissue.

Decreased insulin secretion

Second, cortisol is associated with the accumulation of adipose tissue by inhibiting insulin secretion. The persistently elevated blood glucose levels, combined with inhibition of insulin secretion, lead to starvation of cells due to a lack of glucose. However, these cells need energy, and the only way to regulate this is to send a signal to the brain.

This action leads to overeating, and thus, the excess of unused glucose is ultimately accumulated in the form of adipose tissue. While adrenaline inhibits insulin secretion, cortisol doesn’t, therefore its parameters in states of long-term stress are elevated, intensifying problems with the deposition of adipose tissue.

Increased appetite

Third, cortisol has an effect on increasing appetite and cravings for highly caloric foods. Scientific research clearly shows a direct relationship between cortisol levels and caloric intake. This happens through receptors in the hypothalamus in the brain. Cortisol has an indirect effect on appetite by modulating other hormones and stress factors that stimulate the appetite.

An interesting fact is that there are people who develop metabolic obesity despite having a healthy body weight, and this is closely related to the increased level of cortisol in the blood. The reason for this is excessive stress, which triggers the activity of the hypothalamic-pituitary-adrenal axis (HPA) and the 11β-hydroxysteroid dehydrogenase type 1 enzyme in the abdominal fat tissue and in the liver. This shows that, unfortunately, you aren’t always able to see the results of severe and/or chronic stress in your body.

Summary

The fight against chronically elevated cortisol levels requires major changes in your life that will allow you to redirect stressful factors into improving your coping mechanism, and thus improve your mental health. Sleep, meditation, exercise, a healthy diet, supplementation and skillful stress management techniques will help to lower blood cortisol levels, regulate the hormonal balance and, as a result, get rid of excess body fat.