Cortisol is your body's wake-up hormone. Every morning it spikes to raise blood sugar, activate your immune system, and sharpen focus.

By evening it's supposed to drop to roughly 10% of its morning peak - the condition that allows melatonin to rise and sleep to begin. For most people, that trough never fully arrives.

Cortisol and melatonin work against each other. When cortisol stays elevated in the evening, your brain suppresses melatonin release - directly delaying sleep onset and reducing total sleep time.

You're not bad at falling asleep. Your cortisol is preventing the switch from flipping. Taking melatonin on top of high cortisol is like pressing the gas and the brake at the same time.

Three things are keeping your cortisol elevated long after they should:

• Screens after dark - blue light signals your brain it's still midday. Melatonin doesn't rise.
  
• Unresolved stress - unfinished tasks keep the cortisol tap open, even in bed.
  
• Eating late - food triggers a blood sugar response that pushes cortisol straight into your sleep window.

High cortisol doesn't just delay sleep - it degrades what happens once you're asleep. Deep sleep, where your body repairs tissue and releases growth hormone, is directly suppressed. You end up in lighter stages, waking more often, feeling groggy after eight hours.

The hours are there. The deep sleep isn't.

Most supplements target the wrong thing. Melatonin tells your body it's night - but if cortisol is still high, it doesn't matter.

What actually works:

• Morning sunlight to anchor your cortisol curve so the evening drop happens on time
• Screens off 90 minutes before bed to stop the signal holding cortisol up
• Write tomorrow's list - closing open mental loops lowers the stress response
• The right compounds - L-Theanine, Magnesium Bisglycinate, and Apigenin all work on what cortisol actually disrupts