Guides
Guides
Eight articles covering the evidence, the eye-health basics, and the buying decision. Every factual claim links to its source, and where the evidence is thin we say so rather than filling the gap with confidence.
Last reviewed August 2026. We update a page when the underlying evidence changes, not on a schedule.
Start with the evidence
Evidence · 9 min read
Do blue light glasses work? What 17 randomised trials found
The Cochrane review pooled every usable trial and came back with an uncomfortable answer for the industry. Here is what it measured, what it could not measure, and what that means for you.
Evidence · 10 min read
Blue light and sleep: a real mechanism, a shakier product claim
Evening light genuinely shifts your body clock. Whether a pair of amber glasses does enough to change your sleep is a different question, and the trials are small.
Evidence · 8 min read
How the lenses actually work — and why the percentages mislead
Coating versus embedded tint, what a "blocks 90% of blue light" claim can legitimately mean, and why two lenses with the same number can behave completely differently.
Eye health · 9 min read
Digital eye strain: what reduces it, in order of evidence
The symptoms are real. The causes are mostly behavioural and optical. Here are the interventions professional bodies actually recommend, cheapest and best-supported first.
Buying · 11 min read
The buyer’s guide: how to spend the least on the unproven part
If you have decided to buy anyway, this is how to do it without overpaying: lens type, fit, prescriptions, returns, and the claims worth ignoring.
Buying · 8 min read
Prescription or not? The question that actually matters
An uncorrected prescription causes the symptoms people blame on blue light. Working out which situation you are in is the highest-value thing on this site.
Buying · 8 min read
Fit before style: getting frame measurements right
The numbers printed inside the temple arm tell you more about whether a frame will suit you than any face-shape chart. Here is how to read them.
Eye health · 5 min read
Caring for coated lenses without ruining them
Most lens damage is self-inflicted: dry wiping, shirt hems, hot water, alcohol wipes. A short, practical routine that keeps coatings intact.