How your adrenal glands work

Your adrenal glands are two small glands that sit on top of your kidneys. They make hormones that help you respond to stress, keep your energy and blood sugar steady, manage inflammation and balance fluid and blood pressure.

What they make
The outer part of each gland makes cortisol, your main stress hormone. It also makes aldosterone, which helps balance salt, fluid and blood pressure, and DHEA, which your body uses to make sex hormones like oestrogen and testosterone. The inner part makes adrenaline and noradrenaline, the hormones behind your "fight or flight" response.

How your body handles stress
When your brain senses stress, the hypothalamus and pituitary gland send a signal to your adrenals to release cortisol. Cortisol raises your blood sugar for quick energy, sharpens your focus and dampens inflammation. Once the stress passes, levels settle again.

Your daily cortisol rhythm
Cortisol follows a daily pattern. It's usually highest soon after you wake, which helps you get up and going, then falls through the day so it's lowest at night, when you need to sleep. Long-term stress, poor sleep, illness or skipping meals can disrupt this pattern.

When the rhythm is out of balance
When your stress response is working overtime, you might notice feeling tired but wired, trouble falling or staying asleep, waking in the early hours, needing coffee to get going, afternoon slumps, sugar or salt cravings, anxiety or irritability, getting sick often, low libido, or changes to your cycle.

Testing your adrenals
A single blood test shows your cortisol at one point in time. Saliva or urine tests taken across the day can show your cortisol pattern, and some also look at DHEA and how your body breaks down cortisol. Together they can give a fuller picture of how your adrenals are working.

If any of this sounds familiar, a practitioner can talk it through with you and help you decide whether testing makes sense. If your symptoms are new, severe or getting worse, please see your GP.