Cortisol is a stress hormone that’s really important for your health. But high cortisol levels can cause a lot of problems, ranging from anxiety to diabetes. Here's how to spot the signs of high cortisol, how to test your levels, and what you can do to lower them.
- What is cortisol?
- What are the signs of high cortisol?
- What causes high cortisol?
- How to test your cortisol levels
- How to reduce your cortisol levels
What is cortisol?
Cortisol is a stress hormone that plays a key role in how you respond to stress — your stress response system. For example, if you’re in danger your body releases the hormones adrenaline and cortisol. This increases your heart rate and energy levels so you can quickly react if you're in danger.
On top of helping you respond to stress, cortisol also helps:
- regulate your blood pressure
- convert food into energy
- regulate the effects of insulin — a hormone that controls your blood sugar levels
- reduce inflammation
So while cortisol often gets a bad reputation it’s really important for your health and survival. It’s only an issue if your cortisol levels are high for long periods of time.
What are the signs of high cortisol?
Regular and prolonged exposure to high cortisol levels can wreak havoc on your body. Some of the most common signs of high cortisol levels include:
- weight gain — particularly around your stomach, upper back, and face
- getting sick often
- thinning hair
- bruising and slow wound healing
- weak bones
- muscle weakness
- low sex drive
- high blood sugar
- irregular periods
- anxiety and depression
- sleep problems
- difficulty concentrating
Over time, high cortisol can put you at risk of heart disease, osteoporosis, diabetes, and poor mental health.
What causes high cortisol?
A number of things can cause high cortisol levels, including:
- chronic stress — your body can't gauge the seriousness of a stressful situation so something simple like a traffic jam can kick-start your stress response system
- medication — certain medications like corticosteroids and oral contraceptives might increase your cortisol levels
- oestrogen — high oestrogen levels in women are linked to raised cortisol levels
- an adrenal gland tumour— your adrenal glands produce cortisol so any issues with them can affect how much cortisol is produced
- a pituitary gland issue — an overactive pituitary gland stimulates your adrenal glands to produce too much cortisol
- malnutrition — for example, if you suffer from an eating disorder
How to test your cortisol levels
A blood, saliva, or urine test can be done to measure your cortisol levels.
Cortisol blood test
A cortisol blood test is usually done in the morning when your cortisol levels tend to be at their highest.
Cortisol saliva test
A cortisol saliva test can be done at home at multiple points over the course of one day to help build a better picture of your cortisol levels.
Cortisol urine test
A cortisol urine test involves collecting all of your urine over the course of a day.
How to reduce your cortisol levels
If your cortisol levels are high, lowering them will depend on the underlying cause. If it’s because of issues with your pituitary gland, adrenal glands, or medication you’re taking you’ll need to work with your GP or health professional to lower them. If it’s because of chronic stress, there are lots of lifestyle changes you can make to lower your stress levels:
- enjoy yourself (a lot) — do something you love every day, like dancing or listening to music to improve your mood
- practice mindfulness — for example, daily meditation or yoga
- connect with your friends, family, and even your pet — a strong social support system is important for your mental health
- make sleep a priority — do your best to get 7 hours of sleep every night
- break a sweat — aim for at least 75 vigorous minutes of activity or 150 minutes moderate aerobic activity each week.
- eat a healthy diet — aim for a lot of fruit, vegetables, whole grains, nuts, seeds, and oily fish
- try a supplement — omega-3, vitamin B-complex, magnesium, L-theanine, lemon balm, valerian root, and ashwagandha are linked to lower cortisol levels (it's a good idea to work with a health professional when starting a supplement, particularly if you're on any medication)
Recommended listening for you
Björntorp, P., & Rosmond, R. (2000). Obesity and cortisol. Nutrition, 16(10), 924-936.
Chandola, T., Brunner, E., & Marmot, M. (2006). Chronic stress at work and the metabolic syndrome: prospective study. BMJ, 332(7540), 521-525.
Hofmann, S. G., Sawyer, A. T., Witt, A. A., & Oh, D. (2010). The effect of mindfulness-based therapy on anxiety and depression: A meta-analytic review. Journal of Consulting and Clinical Psychology, 78(2), 169.
Grossman, P., Niemann, L., Schmidt, S., & Walach, H. (2004). Mindfulness-based stress reduction and health benefits: A meta-analysis. Journal of Psychosomatic Research, 57(1), 35-43.
Riediger, N. D., Othman, R. A., Suh, M., & Moghadasian, M. H. (2009). A systemic review of the roles of n-3 fatty acids in health and disease. Journal of the American Dietetic Association, 109(4), 668-679.
Van Eck, M., Berkhof, H., Nicolson, N., & Sulon, J. (1996). The effects of perceived stress, traits, mood states, and stressful daily events on salivary cortisol. Psychosomatic Medicine, 58(5), 447-458.
Torres, S. J., & Nowson, C. A. (2007). Relationship between stress, eating behavior, and obesity. Nutrition, 23(11-12), 887-894.