Light glasses (Luminette, AYO): what the trials use and what they measure

Light therapy glasses (Luminette, AYO, Pegasi, and others) deliver light to the eyes via small LED arrays close to the face. The marketing positions them as portable alternatives to 10,000-lux SAD lamps. The evidence base is real but smaller and the practical effectiveness varies.

The intensity question#

Most consumer light glasses deliver effective intensity at the eye of around 1,500–3,500 lux. This is meaningfully less than the 10,000-lux SAD lamp standard but meaningfully more than typical indoor lighting (100–500 lux).

Because the light source is close to the eye, the angular intensity can equal or exceed a more distant 10,000-lux box at the actual photoreceptor level. The manufacturers' marketing of "10,000-lux equivalent" is technically defensible at the eye level even though the absolute lux output is lower.

What the trials show#

The trial base is modest:

Luminette / similar wearables in seasonal affective disorder. Small trials have reported significant improvements compared to placebo or low-dose controls, often non-inferior to 10,000-lux box therapy. Trial sizes are typically under 50 participants.

Jet lag. Several small trials suggest light glasses may help with eastward jet lag, used at the destination morning. Effects are similar in direction to lightbox therapy but with smaller samples.

Shift work. Small trials in night-shift workers using morning light glasses pre-work suggest modest improvements in alertness during shifts.

Healthy adult circadian alignment. Limited evidence; most positive findings are in populations with disorders or significant time-zone changes, not in well-functioning healthy adults.

The compliance advantage#

The strongest practical advantage of glasses over light boxes: you can wear them while doing other things (eating breakfast, working, reading). A 10,000-lux box requires sitting in front of it for 20–30 minutes daily, which is the main reason people stop using them.

For circadian therapy in particular, sustained compliance matters more than absolute dose. A device you actually use beats a device that sits in a cupboard.

The downsides#

• Visible: wearing light glasses in public draws attention; some users won't
• Cost: typically £100–£200; comparable or more than SAD boxes
• Battery life varies between products
• Eye comfort: some users find the close-range light uncomfortable, particularly with dry eyes
• Not clinical: most are sold as consumer products, not as regulated medical devices

What the evidence does not support#

• "Replace your morning sunlight walk." Outdoor light remains the gold standard for circadian alignment. Glasses are a substitute when outdoor light isn't accessible, not a substitute for choice.
• "Boost dopamine / energy in healthy adults." No good evidence.
• "Cognitive enhancement during the day." Some research suggests bright light improves alertness; whether glasses produce this reliably is less established than light box research.

What we'd actually say#

For someone with seasonal affective disorder who can't sit in front of a 10,000-lux box daily, light glasses are a reasonable alternative with some supporting evidence. They may not be quite as effective as standard light box therapy, but compliance is dramatically better.

For frequent long-haul travellers, light glasses are convenient for in-flight or arrival-day use; the evidence is small but consistent in direction.

For healthy adults seeking circadian optimisation, a morning outdoor walk is cheaper, better-evidenced, and almost always available. Light glasses are mostly for cases where outdoor light isn't accessible.

The "wearable light therapy" market is small but the evidence on the underlying principle (timed bright light shifts circadian phase) is strong. The specific products have less evidence than the principle does.

When to talk to a clinician#

• Suspected SAD or persistent winter depression: see GP first; light therapy is part of treatment, not a self-administered fix
• Bipolar disorder: light therapy can trigger hypomania; specialist supervision
• Macular degeneration or other significant retinal conditions
• Any unusual eye discomfort or vision changes during use