Cortisol: How to Keep the Stress Hormone Under Control

What Is Cortisol and What Does It Do?

Most people know cortisol as the “bad” stress hormone, but the reality is a little more nuanced.

Cortisol’s primary role is to regulate bodily functions according to the body’s daily rhythm. Produced in the adrenal cortex from cholesterol, it follows a distinct pattern: cortisol levels peak in the morning when you wake up, gradually decline during the day, and reach their lowest point at night, only to rise again in the early hours of the morning.

In essence, cortisol is a “wake-up” hormone that:

• Stimulates metabolism,
• Mobilises energy from stored reserves,
• Sharpens alertness and speeds up brain processing,
• Increases heart rate, breathing, and blood pressure,
• Suppresses repair and immune processes that consume energy.

This makes cortisol essential for helping you start your day with energy. When you sleep, low cortisol levels allow your body to engage in immune processes and repair mechanisms.

What Role Does Cortisol Play in Stress?

In stressful or threatening situations, the body releases more cortisol. Historically, this was vital for survival—and still is to some extent. The cortisol surge triggered by stress releases energy and prepares the body for strenuous physical activity, whether that’s fighting an enemy, fleeing from danger, or taking on a physical challenge.

Nowadays, however, we face different types of stress where fight or flight isn’t always an option. In these cases, the cortisol-triggered stress response is left hanging with no physical action to resolve it.

What Causes High Cortisol Levels?

The main causes of chronically elevated cortisol levels include:

• Chronic stress: This could stem from a heavy workload, emotional stress, or difficult living conditions.
• Disruptions in cortisol production: Often due to benign tumours in the adrenal glands, less commonly in the pituitary gland (Cushing’s syndrome).
• Long-term use of glucocorticoid medications: These synthetic cortisol variants suppress the immune system and are used to treat conditions like rheumatoid arthritis, severe asthma, or autoimmune diseases.
• Severe obesity
• Alcoholism

What Are the Effects of High Cortisol Levels?

Chronically high cortisol affects energy metabolism, weakens the immune system, and inhibits growth and repair processes. It also disrupts the balance of other hormones. The consequences of too much cortisol can affect both your physical and mental health:

• Increased blood sugar levels, potentially leading to diabetes
• Raised blood lipid levels
• High blood pressure
• Altered fat distribution: more fat around the abdomen and face, less around arms, legs, and hips
• Greater susceptibility to infections
• Muscle loss
• Bone loss (osteoporosis)
• Reduced libido and sexual function due to low testosterone
• Memory issues
• Depression

How Can You Lower Cortisol Levels?

If your high cortisol levels are stress-related, the best approach is learning to manage stress more effectively. While completely eliminating stress isn’t realistic (or necessary), you can adopt strategies to organise your workload and manage stress more efficiently. This includes being aware of your personal limits and learning to say no when those limits are reached. Regular relaxation breaks, sufficient sleep, a healthy diet, and increased physical activity can all help lower cortisol levels.

If your cortisol levels are elevated due to an underlying hormonal imbalance, medical treatment may be necessary.

Can you reduce cortisol with home remedies? Yes, several home remedies and supplements can support healthy cortisol levels, including B vitamins, vitamin D, and omega-3 fatty acids.

Can a Balanced Diet Help Regulate Cortisol?

Cortisol raises blood sugar and lipid levels. Conversely, high blood sugar and lipid levels can increase cortisol. This means that your diet can have a significant impact on cortisol regulation.

It’s wise to limit animal fats—with one exception: fatty fish like salmon, mackerel, and herring are rich in omega-3 fatty acids, which help lower cortisol. Carbohydrates play an even bigger role. If you want to reduce cortisol, cut back on sugar. Stay hydrated with water or tea instead of sugary soft drinks or juices. Swap white bread, pasta, and pastries for fibre-rich wholegrain alternatives and load up on vegetables. These healthy foods help maintain stable blood sugar levels, which in turn can help keep cortisol in check.