Is my cortisol level to blame for my irritable mood?
The ‘stress hormone’ can alter our metabolism and lead to long-term health issues. So should we be trying to lower its levels?
Like the majority of women I know, I am tired quite a lot of the time. I often wake up bleary-eyed, with a puffy face — if I’ve managed to sleep at all. As I’ve got older I no longer crave breakfast first thing, but am quite happy to wait until lunchtime or sometimes later before I eat. And I have, indeed, put on weight around my middle in recent years.
If my social media algorithms are to be believed, there is one thing behind all these changes: cortisol. “Signs your cortisol is high,” proclaims one post after another, listing tensed neck muscles, irritability, thinning hair and low libido among the other symptoms I might be experiencing (also yes).
“Quit these habits to balance your cortisol,” suggests another, telling me I need to avoid my phone first thing in the morning, stop drinking coffee before breakfast and cut out my high-intensity workouts, all of which are thought to raise cortisol levels.
“Cortisol is a hormone produced by the adrenal glands in the body,” explains Dr Gareth Nye, an endocrinologist. “It’s often termed the ‘stress hormone’, but its main role is in the regulation of glucose, promoting the creation and release of glucose for energy. It can also be found working to reduce components of inflammation in the body.” In medicine, it goes by the name hydrocortisone, Nye adds. Our cortisol levels naturally rise and fall throughout the day. “It’s really what wakes us up,” explains Marina Pavlovic Rivas, founder and CEO of health company Eli, which last year released the first at-home saliva test for cortisol. In the early hours of the morning, cortisol starts to spike naturally, reaching its peak around 30-60 minutes after we wake, to help fuel the brain and muscles after we sleep.
It then naturally falls throughout the day to its lowest point around our normal bedtime. “What’s important is to have a curve — high in the morning and low in the evening,” says Pavlovic Rivas. But there are lots of things that can spike our cortisol throughout the day, from coffee to too much sugar to physical or emotional stress.
Not all of these spikes are unhealthy. “Any trauma or illness will raise the cortisol levels to help the body combat the disease, or heal damaged tissue,” says Nye. The key is to avoid constant high levels of cortisol, which can change our metabolism, alter our cardiovascular system and impair our brain function — ultimately increasing the risk of cardiovascular disease, stroke and obesity.
So how can I tell if my cortisol levels are out of whack? And if so, what can I do about it?
It turns out it’s pretty easy to get your hands on an at-home cortisol test, although prices vary wildly, between £24 to £71 ($50.19 to $148.47). I plump for a basic £29 ($60.64) one from the London Health Company, which comes with everything I need to take an at-home blood sample from my finger. I have to do the test in the morning then send it off straight away.
The results are back within three days, although are disappointingly inconclusive — either I squeezed my finger too hard or something got into the sample. Anyway, points out Pavlovic Rivas, a snapshot of one day’s cortisol reading at a point in the day when my levels would naturally be high anyway won’t tell me much about my overall state of health.
Instead I try her saliva test, which arrives with four testing sticks to use throughout the month that look a bit like pregnancy tests, only you put them under your tongue. An app reads the results and gives your latest score, tells you whether or not they’re elevated, plus suggested actions, eg “try delaying your morning caffeine intake by 90 minutes”. This turns out to be a much better way of keeping an eye on my general cortisol levels and tweaking things accordingly. Indeed, when I do a morning test, my cortisol level, at 81 nmol/L at 7.49am is deemed “good” which in itself makes me feel much calmer. As Pavlovic Rivas points out, “knowing your level is a great first step, but more important is what we do with this information”.
Which is what? Ultimately, we all know we need to eat well, exercise and try to keep stress levels to a minimum. But there are specific things you can do to keep cortisol in check, especially when, as a midlife woman like me, you’re likely to be more sensitive to cortisol spikes. “The number one thing you can do is start eating breakfast again,” Petronella Ravenshear, nutritionist and author of The Human Being Diet, tells me. This helps restore our sensitivity to leptin, the “I’m full” hormone, and helps balance our overall blood sugar levels. Then, says Ravenshear, we need to “stop exercising like fiends”, particularly later on in the day — because high-intensity workouts put us into fight or flight mode, sending cortisol levels soaring. Getting outside first thing can help, as it resets our circadian rhythm. And we should delay drinking coffee in the morning until after we’ve eaten.
Above all, chill out. “Stressing about a hormone related to stress is quite ironic,” points out Nye, “but ultimately, an average person does not need to worry about their cortisol levels.” With that in mind, I’m going to stop measuring mine — and go and have a nice cup of decaf.
The Times
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