Many people focus on sleep supplements, magnesium, blue-light glasses, and evening routines.

But one factor is often overlooked:

The air in your bedroom.

A study compared sleep quality at different CO₂ levels:

• 800 ppm
• 1900 ppm
• 3000 ppm

Everything else remained the same.

The result?

As CO₂ levels increased, sleep quality decreased.

Participants took longer to fall asleep, spent less time in deep sleep, and reported feeling less rested. At 3000 ppm, perceived sleep quality dropped to just 80% of the level seen at 800 ppm.

Why does this matter?

Many bedrooms reach high CO₂ levels overnight, especially when windows stay closed and ventilation is limited.

Before spending money on another sleep supplement, consider the basics:

✅ Ventilate your bedroom before bed
✅ Leave the door slightly open
✅ Keep the room cool
✅ Consider a CO₂ monitor

Sometimes better sleep starts with something as simple as fresher air.