Health fads warn of ‘killer cortisol’—but experts say it’s stress about stress doing the damage

“Lower your cortisol” has become the internet’s go-to wellness advice. But for many, it’s having the opposite effect—raising anxiety and fuelling obsessive habits that aren’t backed by science.

Ruth Clegg, a BBC health reporter, found herself overwhelmed by the pressure to control a hormone she barely understood. Social media bombarded her with warnings that high cortisol could puff her face, expand her waistline, and even make her hair fall out. The supposed fixes? A cocktail of orange juice, coconut water and sea salt, plus lavender balm and supplements galore.

“I didn’t know about my cortisol levels ten minutes ago,” she wrote. “Now I can feel them rising.”

Cortisol, produced by the adrenal glands, plays a key role in our stress response. It gets us up in the morning and helps us sleep at night. But when levels stay too high for too long, it can affect everything from weight to sleep and immune health. Still, top endocrinologists say the online obsession with cortisol often oversimplifies a far more complex issue.

“There are so many other causes for puffiness or weight gain,” says Professor John Wass of the University of Oxford. “Poor sleep, alcohol, salt, medications—cortisol isn’t always the culprit.”

That nuance was missing from Jasleen Kaur Carroll’s social feed when she began experiencing burnout. Running a tech company in her twenties, Jasleen pushed through mental and physical exhaustion until her body gave out. Desperate for relief, she turned to wellness influencers and tried every hack she could find. None worked.

“I did everything,” she says. “Cortisol cocktail, Ashwagandha, turmeric, black pepper, tapping, lavender balm. Nothing helped.”

Eventually, Jasleen was hospitalised. The stress had triggered a severe flare-up of her autoimmune disease, lupus. She lost weight, suffered intense joint pain, and fluid built around her lungs. Doctors warned she may struggle to conceive.

Only then did she realise that fixing her stress symptoms wouldn’t work without confronting the causes. She turned to therapy, addressed past trauma, and began practising mindfulness. Slowly, she recovered.

“Stress is essential—it protects us,” says Neil Shah of the Stress Management Society. “But in a 24/7 world, we perceive threat everywhere. That’s when cortisol becomes harmful.”

Neil recommended Jasleen stand barefoot on grass. She laughed—but tried it. Now she follows a daily routine that includes grounding exercises and breathwork. She also avoids social media where possible.

Mindfulness, exercise, journalling and therapy all show evidence of supporting cortisol regulation. But the key, experts stress, is to stop obsessing over one hormone and address the stressors themselves.

Professor David Creswell, a psychologist and stress resilience researcher, says true stress relief comes from accepting discomfort. “Mindfulness, CBT, movement—all ask us to sit with discomfort. That makes us more resilient.”

Professor Sir Cary Cooper agrees. “The ‘quick fix’ mentality is dangerous,” he says. “If your face is changing or you’re gaining weight suddenly, see a doctor. It could be something like Cushing’s Syndrome—very rare, but serious.”

As for the famed cortisol cocktail?

“It won’t harm you,” Cooper says, “but it’s not a cure. And it definitely won’t fix your life.”

Jasleen now works in digital marketing and has a baby girl—something doctors once warned might not be possible. Each morning, she taps her body, does breathwork, and visualises calm. She knows her limits now and respects them.

“There’s still stress,” she says. “But I’ve got tools—and I’m no longer fighting the wrong battle.”