Maybe you can’t sleep. Or you sleep too much. Maybe you keep breaking out, or getting sick. Perhaps your stomach bloats, your skin sags, you feel shaky. Maybe you can’t focus, eat or get rid of the tension in your spine.

If you’ve scrolled through TikTok lately, you might be inclined to blame one or all of these things on your cortisol levels. Over the past year or so, users have flooded the app with stories about how their supposed cortisol imbalances have led to a range of health issues and concerns.

Cortisol, also known as the stress hormone, is a chemical that helps regulate the way our bodies react to stress. “It’s a hormone that connects the mind and the body together,” said Martin Picard, an associate professor of behavioral medicine at Columbia University, US. Nearly every organ has a receptor that responds to cortisol. It is crucial in helping us function throughout the day, whether by regulating blood pressure or combating inflammation.

That doesn’t necessarily mean that cortisol imbalances are responsible for the various ailments that people are sharing on TikTok, said Nia Fogelman, an associate research scientist at the Yale Stress Center in the US. “I think it’s completely natural and understandable why people want to A, figure out what’s going on with their bodies, and B, to want some one thing that we can fix,” she said. But it’s not that simple.

When we experience stress, the pea-size pituitary gland in the brain — sometimes called the master gland — signals to the adrenal glands perched atop the kidneys, prompting them to secrete and deliver cortisol into our bloodstream.

Our bodies release the chemical when we are faced with a challenge, whether psychological or physical, real or imagined, said Jeanette M. Bennett, a health psychologist who studies the effects of stress on health at the University of North Carolina, Charlotte, US. We release cortisol when we encounter a tangible threat, such as coming across a bear on a hike, but also when we receive an ominous work email. The more threatening we perceive an event to be, the more cortisol we typically produce.

“The mind and the body will respond to the event as if we were in danger of dying, when actually what’s happening is that our sense of self is being threatened,” Picard said.

This is a gift from evolution: cortisol helps us mobilise the energy we need to confront, or flee from, danger, partly by raising the amount of glucose in our blood. It also regulates our metabolism. Our levels fluctuate throughout the day, rising when we first wake up and falling as we drift off to sleep, said Dr Gregory Fricchione, associate chief of psychiatry at Massachusetts General Hospital and a professor of psychiatry at Harvard Medical School in the US.

“Cortisol is your friend,” Dr Fricchione said, “until there’s too much of it.”

We function best when we have the right balance of cortisol. “Our bodies are this harmonic unit,” Fogelman said. But chronic stress can elevate our baseline cortisol levels over time, leading to a cascade of consequences. Persistently high cortisol levels may weaken the immune system, Dr Fricchione said, as well as raise blood sugar levels and blood pressure. There’s also an integral link between cortisol and sleep: we need the hormone level to decrease so that we can fully rest. People with high cortisol often struggle to fall and stay asleep, Dr Fricchione said.

Some mental health conditions, including depression and post-traumatic stress disorder, are associated with cortisol imbalances, said Dr Raza Sagarwala, a resident physician in the department of psychiatry at Vanderbilt University Medical Center, US, who has studied the effects of non-pharmacological treatments on cortisol levels.

Without testing cortisol levels and consulting a physician, it’s almost impossible to determine whether something like acne or poor sleep is definitively linked to hormone imbalances — and cortisol may just be a convenient culprit that people can point to when they don’t have any other clear explanations for their health concerns.

“When people say they have elevated cortisol — I would tell you, you cannot feel that,” Bennett said. But if people are truly worried about their cortisol levels, experts said, they can talk to their primary care doctors about getting tested.

Some small studies have suggested that yoga and mindfulness interventions such as meditation may help lower cortisol levels, Dr Sagarwala said.

Exercise can also be helpful for regulating cortisol, Bennett said, especially moderate physical activity such as jogging or cycling. Those movements prompt your body to mirror your stress response, raising your heart rate and then lowering it once you stop working out. That cycle effectively trains our bodies to activate and shut down our stress response appropriately.

“Stress is not a bad word,” Dr Fricchione said. “Just being a living organism means that there’s going to be stress.”

NYTNS