You need it to get out of bed in the morning, but when it's out of whack, cortisol can affect everything from sleep to mental health, digestion, weight, skin and even fertility. Here's how to stop this stress hormone from ruling your life

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As hormones that can take a hike/holiday go, the ones associated with stress are likely up there on the list. All of us are familiar with that ‘fight or flight’ rush of adrenaline, but you’re probably less consciously aware of the body’s other primary stress response hormone, cortisol. When it's out of whack it can affect everything from sleep, to mental health, digestion, weight, skin and even fertility.

It’s high time we got our heads around it, however, as a recent YouGov and Mental Health Foundation survey involving 4,619 respondents reported that 74 per cent of us have felt so stressed in the past year that we’ve been overwhelmed and felt unable to cope with daily tasks.

Aspects of modern life such as ever-present technology (12 per cent cited the pressure to respond to message straight away as a key stressor) and social media comparison (49 per cent of 18-24 year old reported this as a significant source of stress) are pushing our cortisol levels up to consistently chronic levels.

It’s worth bearing in mind that cortisol always ain’t the enemy here. In fact, it plays a key role in getting you out of bed in the morning, as GP and author of a bestseller (telling in itself) The Stress Solution  Dr Rangan Chatterjee  explains:

“One of its fundamental roles is to help set our body's daily circadian rhythm . Cortisol should be high in the morning, which helps to give us energy and get us out of bed. Throughout the day it starts to decline until it reaches its lowest levels in the evening, which helps us to switch off and, hopefully, fall into a deep, relaxing slumber.”

Except... what if you’re still buzzing come bedtime and sluggish first thing? Is your cortisol release system misfiring? Are you actually nocturnal? Dr Chatterjee says that while there's a saliva test for cortisol levels (mainly available privately and you have to do spit tests at different times of the day) your general mojo and a daily diary could help to identify whether your levels are through the roof at the wrong times.

“I rarely measure the cortisol levels of a patient if I think that they are chronically stressed. You can usually get a good idea of where their cortisol levels are at from taking a detailed history. If someone is lacklustre in the morning and struggle to get out of bed, that can sometimes be a sign that their morning cortisol level is sub-optimal. Almost always, if you work on optimising a series of lifestyle factors, you can start the process of re-balancing levels.”

With that, here’s how cortisol can impact on different aspects of your body and mind, and how to get back on an even cortisol keel (without stressing out about it because... irony).

Cortisol can trigger IBS

Irritable bowel syndrome  is a  growing problem among women especially  and GP  Dr Jane Leonard  underlines that chronically high levels of cortisol could be a factor:

“Our brain and gut are extremely closely linked. When we are stressed, cortisol is released and this directly affects our gut. It is closely linked to IBS, and symptoms such as abdominal pain, bloating , diarrhoea and acid reflux are classically triggered in times of stress and anxiety.”

Dr Chatterjee thinks that “stress is probably one of the biggest contributors to poor gut health” with recent Mintel stats supporting this idea - a whopping 86 per cent of Brits have reported suffering from some of gastrointestinal problems in the past year, with 30 per cent of these attributing their gut health issues to high stress levels.

Even more problematic, the stress surge and resultant cortisol release can become a vicious cycle, as Dr Chatterjee illustrates:

“The gastrointestinal tract is sensitive to emotion. Anger, anxiety, sadness, elation -  all of these feelings (and others) can trigger symptoms in the gut. A person's stomach or intestinal distress can be the cause or the product of anxiety , stress or depression . This is especially true in cases where a person experiences gastrointestinal upset with no obvious physical cause. For such functional GI disorders, it is difficult to try to heal a distressed gut without considering the role of stress and emotion.”

Cortisol can make you more likely to put on weight

How very wonderful. Dr Leonard clarifies:

“Cortisol stimulates fat and carbohydrate metabolism for fast sources of energy, in turn stimulating insulin release in order to maintain blood sugar levels. The end result of these actions can be an increase in appetite and increased cravings for sweet, high fat and salty foods. The combined effect can lead to weight gain.”

Dr Chatterjee encounters this more and more often in clinic

“If you are chronically stressed and your cortisol levels are persistently raised, your body often thinks that it is under attack. As a result, it starts to hold onto weight as a means of survival. I’m noticing this becoming increasingly common in my practice- patients are unable to lose weight, despite changing their diet and moving more, because they have not addressed their stress levels.”

Cortisol can create an 'insomnia loop'

Mainly because it should be naturally tailing off by lights out, so if cortisol is kicking in late at night, it’ll almost certainly negatively impact on the quality of your sleep, or whether you’re able to nod off at all. Dr Chatterjee reckons that stress and sky-high cortisol is the most common reason that people experience sleep disorders, while Dr Leonard brings up that vicious cortisol cycle business again:

“Poor sleep leaves you feeling tired and unrefreshed in the morning, which in turn causes our cortisol levels to climb higher during the day. This then creates an  insomnia  ‘loop’ and raised cortisol levels, with insomnia causing high cortisol for up to 24 hours. Interruptions to sleep, even if brief, can also increase your levels and disrupt daily hormone patterns.”

Hold on for cortisol lowering sleep tips coming at the end…

Cortisol can be a risk to mental health

Principally because feeling regularly stressed out can lead to bouts of low mood and anxiety, perpetuated by the effect of high cortisol levels on your sleep. Dr Chatterjee thinks that many of us underestimate the impact of disturbed sleep on our mental wellbeing:

“Stress can play havoc with our mental health, not least because it negatively affects our ability to sleep. When we haven't slept, our emotional brain, the amygdala, can be up to 50 per cent more reactive, meaning that we will have a tendency to overreact and become very emotional when we normally might not.”

It’s bad news for reactive skin

Chronically elevated cortisol can spell problems for skin too according to Dr Leonard:

Stress is closely linked to skin problems ; it can either be the direct cause or if you’re prone to sensitivity or particular skin conditions, it can cause flare-ups in existing sufferers. Acne, eczema  and psoriasis  are all very reactive to high cortisol levels.”

The high cortisol cycle strikes again, because, you guessed it, skin problems can be extremely stressful, which leads to... you know the drill.

It can affect your chances of getting pregnant

Sustaining high cortisol levels “has a significant effect on fertility” according to Dr Leonard, and Dr Chatterjee agrees that stress plays a vital role in conception:

“Over the years I have observed that women who are chronically stressed can sometimes struggle to get pregnant. If you consider this on an evolutionary level, our stress response is activated when the body thinks that we are in danger. If that is the case, the body will prioritise bodily processes that are critical to survival and switch off ones that are deemed non-essential, like reproduction.”

It’s for this reason that Dr Leonard emphasises that, as well as preparing your body physically in order to  increase your chances of conception , “it’s important to consider stress levels too to ensure that you are as healthy as possible to conceive and carry a baby throughout your pregnancy.”

It’s a double-edged sword in the gym

Dr Leonard affirms that exercise is an excellent stress-reliever  and is a “well-known treatment alongside antidepressants and counselling to manage mental health problems such as anxiety and depression.” In this way, exercise can help you to optimise cortisol levels by reducing your overall feelings of stress, however, overdo exercise and things could swing the other way:

“Exercise can also be detrimental when is it done to excess as it is a means of increasing cortisol levels by creating extreme physical stress on the body, which can fuel adrenal fatigue.”

Said fatigue then rebounds on your PB attempts according to Dr Chatterjee:

“Chronic stress can affect our ability to perform physically, and while it can do this by many mechanisms, one essential consideration is sleep. Sleep is the best performance-enhancing 'drug' we have available to us and, as we’ve discussed, chronic stress impairs sleep, and in doing so we’re less likely to achieve our fitness aims.”

Balance and adequate rest are key are to keeping on the right side of the cortisol line.

Cortisol can affect memory

As in every other aspect of our life, a little cortisol at the right time can pay dividends - Dr Chatterjee points out that cortisol can improve brain function. There’s a ‘but’ coming though:

“Too much stress, day in day out, and the raised cortisol levels that prompts kills nerve cells in the memory centre of your brain, the hippocampus, which negatively affects our memory.”

If you’ve ever felt frazzled and wired and forgotten your house keys, soaring cortisol could be the (indirect) culprit.

5 ways to balance your cortisol levels

Balancing cortisol is a key theme in Dr Chatterjee’s stress solution programme - you can watch his stress tips here , but his and Dr Leonard’s five ultimate cortisol levellers are as follows:

1. Have a phone-free golden hour when you get up every day to allow your cortisol levels to rise gently rather than spike as soon as you scroll. Ditto at the end of the day to allow cortisol levels to dip.

2. In the same vein, get away from a pinging inbox and have a tech-free lunch break, even if it’s just for 15 minutes.

3. Get a daily dose of nature - a minimum of five minutes. Even staring at a tree has a cortisol lowering effect. Take in nature for as long as you can and you should notice your stress response receding.

4. Lower cortisol surges during your commute (a common stress trigger). Instead of checking up on work and getting stressed out before you’ve even arrived at the office, use the ‘dead time’ in a relaxing way. Listen to some music you love or try something new, download an uplifting or inspiring podcast or do ten minutes of meditation using a meditation app such as Calm .

5. Schedule in stress reduction techniques at nighttime. Five minutes of gentle yoga stretches  or a warm bath can work wonders for some, but stress relief and relaxation are always a really personal choice. Fundamentally you need to be getting the balance right between sleep, exercise, a healthy diet and having fun, without burning the candle at both ends. Easier said than done, but tweaking the formula to find something that works for you is essential to effective stress, and therefore cortisol, management.

In short, it’s that bloody moderation thing again, but boring as it seems, getting off the cortisol steam train by way of instilling balance is worth it in the short and long-term. Just don’t get stressed out in the process.

Stress: our top 10 questions answered by Dr Rangan Chatterjee

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