You are exhausted all day and cannot sleep at night. You crash every afternoon like clockwork. Then something turns back on around nine or ten, exactly when you should be winding down. When you describe this to a doctor, you get told it is stress. That answer is not wrong. It is just not finished.

In this episode, Rachel explains what cortisol actually does and why the timing matters far more than the amount. Healthy cortisol follows a curve: it rises sharply in the first thirty minutes after you wake, tapers through the day, and bottoms out late at night so melatonin can do its job. Think of it as a thermostat rather than a switch. A thermostat is not judged by how much heat it makes, but by whether it makes heat at the right times. When that timing shifts, your energy does not disappear. It arrives on the wrong schedule.

What you'll ...