Cortisol

Yes, but that's only part of the job. Cortisol rises when you're under stress, and it also helps regulate blood sugar, blood pressure, inflammation, and your sleep-wake cycle. It follows a daily rhythm, peaking in the morning and dropping overnight. Having it isn't the problem. Having it badly out of rhythm or far too high or low can be.

Cortisol is a steroid hormone, made from cholesterol in the adrenal glands, and it belongs to a group called glucocorticoids. That's different from anabolic steroids used for muscle building. Medications like prednisone and hydrocortisone are synthetic drugs designed to act like cortisol, which is why they can affect inflammation and the immune system.

No. Cortisol is the active hormone your body makes. Cortisone is a related, less active form that your body can convert into cortisol. In everyday use, "cortisone shot" usually means an injection of a corticosteroid drug for inflammation, and the specific drug may not be cortisone at all. Your prescriber can tell you which one you're getting.

Partly. Very high cortisol over a long time, as in Cushing syndrome, is linked to fat gain around the midsection. But the social media idea that everyday stress alone gives you a distinct "cortisol belly" isn't well supported. Stress can change sleep, appetite, and habits, which affect weight, so cortisol is rarely the only factor.

The evidence is thin. You can't "detox" cortisol, because your body regulates it on its own. Some supplements, such as ashwagandha, have small studies suggesting lower stress scores or cortisol, but trials are limited and the products vary. Supplements aren't proven to fix belly fat, and they can interact with medications, so check with a clinician first.