Stress isn’t just in your head. When faced with stressful situations, the body undergoes a series of changes designed to help you escape whatever near-death experience is causing you to freak out. The problem is, in the modern world, stress isn’t typically caused by coming face-to-face with a lion. It’s about work or family problems or not having enough money to pay the rent on time. These stressors don’t go away—there’s always something to stress out about. This kind of chronic stress can have a major impact on your health, as this TED-Ed lesson by physician Sharon Horesh Bergquist explains. 

In response to stress, the adrenal gland releases hormones like cortisol and adrenaline. These make their way to the heart, raising your blood pressure and eventually leading to hypertension and the buildup of cholesterol. These stress hormones can also affect parts of the body you might not typically associate with stressing over an upcoming test or job interview, like the gut. Stress can lead to irritable bowel syndrome and heartburn, and it can even change your gut bacteria. It can make you crave comfort foods, and cause you to build up stores of fat. It can cause acne, hair loss, and muscle tension. As if all that weren't bad enough, it can also take a toll on your immune system, reducing your defenses against sickness and slowing the healing process after you get hurt. 

With animations reminiscent of Pendleton Ward’s Adventure Time, this video looks cute, but a warning: it may make you stressed out about stress. 

[h/t: The Atlantic]