February 20, 2026
Warm screens, cold takes
Blue light filters don't work
Scientist says dim your screen; commenters: let us keep the cozy orange
TLDR: A neuroscientist argues blue filters don’t fix sleep and that lowering screen brightness is what matters. Commenters split between “placebo comfort is still comfort” and “stop obsessing,” with demands for real tests on apps like TikTok—proof that bedtime battles are happening in Settings, not science labs.
Blue light filters are getting dragged. Visual neuroscientist Patrick Mineault says the real sleep villain isn’t “blue,” it’s brightness. In plain English: your body clock cares about how bright your world is, not the orange tint on your phone. He argues that a special set of light-sensing cells in the eye respond broadly to cyan/green light, so turning your screen pumpkin-orange won’t magically knock you out—dimming it will. His own measurements even show dark modes and design tweaks can slash screen brightness by over 90%.
And then the comments lit up. One camp rolled their eyes at sleep-optimization culture. “Maybe stop optimizing and live,” groans debo_, who escaped insomnia and doesn’t miss the obsession. Another camp says, sure, maybe it’s placebo—but it’s a working placebo. aethrum swears warm tones soothe eye strain and asks the million-dollar question: “Why does he care?” Meanwhile, snet0 drops the vibe-check: if it feels better, that’s a win. The author’s snarky aside—“Aggravatingly, yes” people still use Night Shift—only poured gasoline on the fire.
There’s also the practical crowd: pier25 wants to know if TikTok and YouTube get the same huge brightness cuts as Google, X, GitHub, and VSCode. Translation: people want receipts, not theory. So, science says “dim it,” users say “leave our cozy amber screens alone,” and everyone agrees on one thing: sleep is hard, screens are bright, and the real late-night fight might be in your settings, not your circadian buzzwords.
Key Points
- •The article argues blue light filters do not improve sleep or prevent circadian delays.
- •The master circadian clock resides in the suprachiasmatic nucleus (SCN), which coordinates body rhythms via neuropeptides and hormonal signals.
- •Circadian light input comes from ipRGCs containing melanopsin, which has broad sensitivity peaking between blue (S) and green (M) cones, covering cyan/blue/green.
- •Because melanopsin’s sensitivity spans a broad range, merely reducing blue wavelengths is insufficient to meaningfully affect circadian signaling.
- •The author contends the effective lever is reducing total luminance (overall light level), not shifting display color spectrum.