Cortisol Blood Test

Cortisol is your body’s main stress hormone, produced by the adrenal glands. It plays a key role in regulating metabolism, blood sugar, inflammation, and the body’s response to stress. Balanced levels help with energy, mood, and overall health, but too much or too little can cause issues.

You can naturally lower cortisol through stress management techniques like mindfulness, exercise, and quality sleep. A balanced diet, reducing caffeine and alcohol, and maintaining stable blood sugar levels also help. Identifying and addressing underlying causes, such as poor sleep or chronic stress, can make a big difference.

High cortisol can result from chronic stress, poor sleep, excessive caffeine, intense exercise, or underlying conditions like Cushing’s syndrome. Certain medications, including steroids, can also raise cortisol. Lifestyle adjustments and medical guidance can help restore balance.

The healthy range for cortisol is between 166-507 nmol/L.

We looked at over 4,750 blood test results from Forth customers in February 2025 and found the median cortisol level for men and women was 359 nmol/L and 364 nmol/L respectively.

Although both sexes have a median level within the healthy range, 21.7% of men and 27.3% of women had cortisol levels outside the healthy range, with the majority of these having high cortisol levels.

A cortisol level below 166 nmol/L is consider low. Only 6% of Forth customers had a low level.

Extremely low cortisol can indicate adrenal insufficiency, a condition where the body doesn’t produce enough of this vital hormone. Symptoms include fatigue, dizziness, low blood pressure, and salt cravings. If cortisol drops too low, it can be life-threatening, requiring urgent medical attention.

Cortisol belly refers to stubborn abdominal fat linked to high cortisol levels. Chronic stress can lead to increased fat storage around the midsection by affecting metabolism and insulin regulation. Managing stress, improving sleep, and balancing blood sugar can help reduce cortisol-related weight gain.

Symptoms of high cortisol include fatigue, weight gain (especially around the belly), anxiety, poor sleep, high blood pressure, and frequent illness due to a weakened immune system. If left unchecked, prolonged high cortisol can contribute to long-term health issues.

Yes, all our test kits are delivered in plain, unbranded packaging to protect your privacy. There is no mention of the test type or company name on the outside of the package.

No, you can choose to have a healthcare professional collect your blood sample for you either at home or one of our many clinics around the UK. You can select your collection method when you add a test to your basket.