To understand why toxic stress causes so much harm while children are developing, we have to understand the body’s natural response to stress.

Imagine you're face-to-face with a grizzly bear. How would your body react? Your heart would begin to race and your breathing would become rapid. You're in what’s known as flight or fight, or stress response. Your body seizes up. A flood of hormones like adrenaline and cortisol are released into your bloodstream, triggering glucose and fats to run for cover and store up in your body for just in case.

But then the bear shrugs and walks away. The threat is gone. You enter the second half of the fear cycle: recovery and relaxation. Your body returns to its normal state of homeostasis. You breathe a sigh of relief, knowing that you’re safe.

Now, imagine that the bear lives with you in your home. The threat never really leaves and it’s never okay to relax. What happens to those stress hormones and physical responses in our bodies? They never go away; instead, we live in a constant state of hyperalertness, bodies constantly flooded with stress hormones that are now toxic to us.