Known as the “stress hormone,” cortisol is often blamed for everything from increased appetite and sleep problems to belly fat and bloating. But this hormone, which is produced in the body’s adrenal glands and released into the bloodstream, is also essential to good health.
“In fact, it plays a key role in regulating metabolism, blood pressure, blood sugar and many other things,” says Dr. Hormones, health, and human potential (Sequoia) “Too little cortisol can have serious health consequences, but certain lifestyle choices can lead to unwanted increases in this hormone that are avoidable.”
In healthy people, cortisol levels rise and fall throughout the day. Your body clock tells you to stay balanced, peaking in the morning and gradually declining at night as you get ready for sleep. Excessive stress, poor diet, and inadequate exercise can all lead to cortisol spikes. Years of research have shown that chronically high cortisol levels are associated with increased weight, BMI, and waist circumference, as well as impaired memory and thinking skills. So how can you stay in balance?
Stefania Perfini, LA WAZIYA PHOT/GETTY IMAGES
Reduce your caffeine intake (wait until mid-morning for your first drink)
Excessive caffeine intake (five to six or more cups of coffee per day) is known to increase cortisol levels, but timing also matters. Several studies, including one published in the journal Pharmacology Biochemistry and Behavior, have shown that drinking coffee before strenuous exercise or when you’re feeling stressed amplifies the effect. “The worst thing you can do for your cortisol levels is skipping breakfast and going to the gym first thing in the morning with just black coffee or going for a hard run or bike ride,” says Key. “This puts your body in a stressed state, which will almost certainly increase cortisol levels.”
Ideally, you should wait to have your first cup of coffee until after your morning workout, then have another cup mid-morning, before your body’s cortisol levels naturally rise for the second time around midday.
• I’m 59 but my biological age is 21. Here’s how I did it
Remember that adequate levels of cortisol are important for good health.
Although very high (or very low) levels can be harmful, cortisol isn’t all bad: For one, it has the opposite effect to the sleep hormone melatonin, giving you more energy in the morning, it also positively influences your response to stress, activates the liver and pancreas and increases glucose production for the brain and muscles, making you mentally alert and ready to move quickly and focus when needed.
“We absolutely need some cortisol to stay healthy. Normally, cortisol rises rapidly in response to stress, but then goes back down to baseline levels,” says Key. “Cortisol helps regulate many biological functions and affects most cells in the body.” Only when we’re in a chronic state of stress, or when our body is repeatedly subjected to multiple physical stressors, do our cortisol levels stay high enough to potentially cause damage. And because our bodies can’t tell the difference between the stress of a work deadline and the stress of a high-intensity interval training (HIIT) session, we need to control both of these stressors as much as possible.
Go for a run, but at a slow pace.
A slow morning jog is more effective at balancing cortisol levels than a harder, faster run or bursts of sprinting as interval training. Key suggests jogging at a conversational pace to find your ideal running speed.
Fredrik Nystrom, a professor of cardiovascular medicine at Linköping University in Sweden, found that even in healthy runners, a fast run can trigger a cortisol spike. Nystrom’s study subjects started one day by running 3.4 miles (5 kilometers) at maximum intensity before breakfast, then took the same time and length of rest the next day, after which the difference in their blood cortisol levels was measured.
“we, [hard] “Running produced a rapid increase in blood cortisol levels, and salivary cortisol levels remained elevated until bedtime on the day of running,” Nystrom reported. “It was only by the next morning that salivary cortisol levels returned to normal.”
Key says that eating breakfast before a hard run can help counter some of the effects. “But I wouldn’t recommend sprinting 5K every day,” she says. “Instead, have a few days where you jog or walk at a slower pace.”
EMS-FORSTER-PRODUCTIONS/Getty Images
Meals should be eaten regularly
Hormones, including cortisol, depend on regular meals to stay in balance, Key says. In a 2021 study published in the journal Endocrinology and Metabolism, researchers found that intermittent fasting can alter the levels and secretion of many hormones, including cortisol.
“We’re used to fasting overnight, but adding an unexpected period of fasting increases cortisol, the stress response hormone,” she explains, which contributes to fat storage, especially around the abdominal area.
If, like me, you’re not under a lot of stress (and therefore unlikely to have constantly high cortisol levels) and you practice time-restricted eating (cramming your meals into a few hours each day), the impact of cortisol production is likely to be minimal. But if you fast at more irregular times, such as on the 5:2 diet, where you eat normally for five days and restrict your calorie intake for two days, then fasting can exacerbate the “cortisol belly.” If you do fast, don’t overdo it, advises Key.
Don’t skip breakfast
One of the worst ways to increase your cortisol levels is to skip breakfast. “It’s becoming very common for people to skip breakfast and go straight to work or the office without eating anything,” says Key. “This is bad news for your body because prolonged fasting allows stress to build up and increases cortisol production.” Breakfast plays a key role in regulating cortisol levels, says Key. “We should all make sure we eat something before we step out the front door.”
Rybko Smokovski/Shutterstock
Take a 20-minute walk every day, preferably in nature.
Getting outside for 20 minutes, preferably in a green space, can help tame high cortisol levels, according to University of Michigan scientists who studied the effects of taking what they call a “nature pill” every day in urban areas over an eight-week period.
Mary Carol Hunter, an associate professor of ecology at the University of Michigan, reported in the journal Frontiers in Psychology that participants were allowed to choose the time, duration and location of their nature walks, but the only rules were that they had to take place during the day, not involve strenuous exercise, and not while using their cell phones or reading. Participants were asked to walk outdoors for at least 10 minutes three times a week, and cortisol tests were recorded. The results showed that walking or sitting in nature for 20 minutes was enough to significantly lower cortisol levels, and immersing oneself in nature for 30 minutes reduced stress hormone levels even more significantly.
• How to get a flat stomach at any age – for men and women
Exercise is good, but recovery time is just as important
Regular exercise plays an important role in overall cortisol control. A study from the University of Westminster found that active people have a lower cortisol response to stress than less active people. Extremely intense exercise can also temporarily increase cortisol levels. However, a review published in the Scandinavian Journal of Sports Medicine and Science found that after a single HIIT session, cortisol levels were significantly elevated for up to two hours, but returned to baseline after 24 hours.
“High-intensity exercise is a form of stress for the body,” Key says. “What the research shows is not that you should avoid hard exercise altogether, but that you should consider recovery to avoid chronically elevated cortisol levels.”
Her preferred method is to do a high-intensity workout in the morning every few days. “I make sure I’m well rested and well-fed before I go out,” says Key. “And the key is to recover throughout the day, and to substitute gentler types of exercise rather than doing hard workouts every day in a row.”
Try some “sleep yoga” before you go to bed
“Cortisol levels naturally fluctuate according to the cycle of your biological clock,” says Key. “To maintain this rhythm, it’s really important to get enough sleep regularly.” Because cortisol’s role is to keep you awake, too much of the stress hormone can disrupt your sleep and wake you up in the middle of the night. “If you’re having trouble sleeping, it’s important to avoid anything that might increase your stress levels at night,” says Key.
This includes hard workouts at the gym, checking work emails late into the night, and endlessly scrolling through your news feed. In a group of women studied by sleep scientists from the Universities of Glasgow and Stirling, regular exercise, such as daily walking, has also been shown to regulate both cortisol secretion and sleep quality. The All India Institute of Medical Sciences has shown that practicing yoga nidra (a type of guided meditation) before bed reduces cortisol levels in people with chronic insomnia.
Should you be worried about “cortisol face”?
TikTok users are blaming stress hormones for their round, puffy faces, coining the term “cortisol face.” Should you be worried? Chronically high cortisol levels can affect your appearance, but this is extremely rare.
“Serious medical conditions can occur when the adrenal glands produce too little cortisol, as in Addison’s disease, or too much, as in Cushing’s disease,” says Key. “But these are relatively rare.” A round face, puffy body and thin arms and legs, unexplained weight gain, and fat around the base of the neck are symptoms of Cushing’s disease, and anyone experiencing these symptoms should see a doctor. In most cases, temporary facial swelling is just a side effect of bad habits like drinking too much alcohol, eating lots of processed foods, and not getting enough sleep, all of which can spike cortisol levels.
Start swimming
Neuropsychiatrists at Renmin Hospital of Wuhan University found that gentle swimming has a stress-reducing effect and helps lower cortisol levels, while sports scientists writing in the International Journal of Environmental Research and Public Health suggested that gentle swimming for 60 minutes a day, five days a week for a month, helped control cortisol levels in unstressed rats, but didn’t see the same effect when stress levels were already high.
