Blue-Light Hygiene After 10 PM — Evidence & Easy Fixes

The Light You Don’t Notice Can Delay Your Sleep by an Hour

Screens are part of night work—but so is the hidden cost. Blue light from phones and laptops suppresses melatonin, delays deep sleep, and reduces next-day alertness. Here’s what the science says—and what to do about it by 10 p.m.

1 · How Blue Light Affects Your Brain

The short-wavelength (460–480 nm) blue spectrum keeps you alert by tricking your brain into thinking it’s daytime. But exposure after 10 PM can delay melatonin production by up to 90 minutes¹, reduce REM sleep, and cause next-morning fatigue.

2 · Proven Ways to Cut the Harm

• Reduce exposure after 9:30 PM. Best: screens off. Realistic: filter the light.
• Use Night Shift (Apple), Night Light (Windows), or f.lux (cross-platform).
• Blue-light blocking glasses: amber or red lenses block 80–99 % of the harmful spectrum.
• Switch room lights to warm tones (under 3000K). Avoid LED-white or bright task lighting.

3 · The ESWA Night Ritual (What We Do)

1. 10:00 PM: Turn on f.lux + switch to warm lamps only
2. 10:15 PM: Finish last focused task block
3. 10:20 PM: Log thoughts → close tabs → dim brightness
4. 10:30 PM: Magnesium glycinate + water
5. 10:45 PM: Stretch or read physical book → bed by 11:00 PM

Bonus Tip: Use Physical Filters for Phone

If you're prone to doom-scrolling: Try an amber film over your screen, or get a “sleep phone” with limited apps + dimmed display.

Key Takeaway

You can’t out-caffeinate bad sleep. If you’re doing focus work after 10 PM, pair it with blue-light hygiene to protect your brain. Then support your wind-down with hydration, magnesium, and stillness—not another screen.

Working late tonight? Block the blue. Take an ESWA Mint earlier, then slide gently into sleep. Shop ESWA Focus Mints →