The way we think about stress has undergone a massive transformation over the last couple of years. We’re now more clued up than ever about how stress can impact our gut health, sleep and immune system, as well as how things such as exercise and drinking caffeine can cause levels of the stress hormone cortisol to rise and fall.

But what if we told you that cortisol wasn’t all bad? While it’s responsible for many of the unpleasant symptoms we associate with stress – disrupted sleep, difficulty concentrating, a rapid heartbeat – our bodies need cortisol to function. The difference between dealing with these uncomfortable symptoms and going about your day-to-day without a care in the world isn’t ridding yourself of cortisol altogether – it’s keeping it stable. So, how can you do that?  

Before we get into the nitty-gritty, let’s take a moment to remind ourselves what cortisol is. Part of the reason why cortisol gets such a bad rap is because it’s commonly known as the stress hormone, but we know that stress isn’t always a bad thing: a moderate amount of stress, known as eustress, gives us the energy and motivation we need to get things done.

Cortisol is always present in the body, even when you’re chilled out watching the TV in the evening. It’s only when you encounter emotional or physical stress – such as a big meeting at work or an intense workout – that more cortisol is released to help you deal with the ‘threat’ you’re facing. This cortisol spike is what leads to the stress symptoms we’re all familiar with.

“Cortisol is required for the healthy functioning of the body, both under resting and stressed conditions,” explains Professor Sarnyai, a neuroscientist and chief scientist at the supplement brand Ally No.1. “When our body is unable to produce cortisol due to an endocrine disorder called Addison’s disease, the therapeutic replacement of cortisol is required.” 

Cortisol is not inherently bad, even at high levels. Our cortisol levels are designed to rise when we encounter a stressful situation to help us survive. In fact, after our body responds to a threat with an initial spike in adrenaline, cortisol production is ramped up to keep our sympathetic nervous system in full swing, so we stay alert and ready to pounce. It’s only when our cortisol levels remained elevated for a long time – also known as chronic stress – that things go awry.

But it’s not just when we’re under threat that cortisol performs an important role. When our circadian rhythm is in check, it plays a vital role in the sleep-wake cycle, counteracting the depressant effect of melatonin to wake us up in the morning and help us feel alert and ready to face the day.

And then there’s its role in immunity. “Cortisol activates the immune response and helps the body to protect itself from infections in the short term,” Prof Sarnyai explains. Elevated cortisol levels during an infection can help to regulate the body’s inflammatory and immune response.  

Cortisol also plays an important role when it comes to our blood sugar. While insulin reduces blood sugar, cortisol increases it – and both play an important role in ensuring things remain stable throughout the day. While high blood sugar tends to be more of a concern than low blood pressure, not having enough cortisol to balance out the insulin could lead to dangerously low levels.

“In the brain, cortisol is also important in the formation of memories, as well as for the healthy regulation of emotions,” Prof Sarnyai adds. It’s for this reason why you’re more likely to remember things you learned in high pressure situations – our body is primed to store information when we’re under threat just in case that information is needed to survive in the future. 

To ensure you’re able to function at your best, you want to keep your cortisol levels balanced. They might spike in response to a threat or fall when you’re asleep, but you want them to return to a comfortable ‘middle ground’ in the aftermath.

Signs that your cortisol levels are too high might include having trouble switching off at night, feeling irritable or struggling with intestinal issues. Some techniques to rectify this could involve having a structured wake-up and bedtime routine, spending time with friends and family or avoiding habits that you know tend to contribute to your stress levels, like scrolling through social media in the evenings or starting the day by watching the news.

On the flipside, your cortisol levels may be slightly too low if you consistently find it hard to wake up in the morning or feel lethargic all day. The tricky thing is that you can feel like that if you’re living with chronic stress too – so if you’re snowed under at work, exercising hard or going through a difficult patch, then rest and stress management is probably your best option. 

If you have no obvious cause for tiredness, however, try giving HIIT a go and getting some early sunlight exposure to regulate your circadian rhythm. And if you don’t notice an improvement, it’s always a good idea to talk to your GP about ongoing energy issues or stress management. 

Images: Getty