There’s not a human on the planet who’s immune to stress. It’s a natural reaction designed to help you face dangerous, threatening situations by stepping up to the plate — or running like hell.
In the short term, this is highly effective: Your body releases a bunch of hormones; boosts your blood pressure and heart rate to send blood to the head, heart, and muscles; and suppresses nonessential bodily functions (like digestion, immune function, and motivation) so you can Get Shit Done.
The problem is that the body isn’t equipped to handle chronic stress, a fixture of today’s typical work environment. And as smart as humans are, we’re not evolved enough to differentiate between physical, life-threatening challenges and emotional ones. So the body responds to a stupid work deadline as though a tiger’s got you cornered — and you end up with symptoms like headaches, muscle tension, an upset stomach, change in appetite, difficultly concentrating, insomnia, irritability, and premature aging.