Cortisol is a hormone produced by the adrenal glands, which sit atop the kidneys. It’s often referred to as the “stress hormone” because it’s released in response to stress. Cortisol helps the body prepare for a “fight-or-flight” response. It increases heart rate, blood pressure, and breathing, and it also diverts blood flow to the muscles.
Cortisol is essential for survival, but chronic stress can lead to high levels of cortisol, which can have negative effects on health. High cortisol levels can increase the risk of obesity, heart disease, diabetes, and depression.