Blue light is a high energy, short wavelength light; essentially the bright, buzzing colour from your phone, laptop and TV screens. It’s mostly from the sun, but those gadgets pump it out too. Blue light tricks your brain into thinking it’s daytime, which stops your body from releasing melatonin, the hormone that helps you relax and get a good night’s sleep.

Blue light glasses filter out part of the blue light spectrum from screens and artificial lighting. The lenses have special coatings or tints that either absorb or reflect blue light, often giving them a slight yellow or amber hue. This helps reduce eye strain, headaches and blurry vision and may even help you sleep better by limiting melatonin disruption from late-night screen time.

Wearing daytime blue light glasses while indoors, especially when you’re glued to screens or under harsh LED lighting, is totally fine and can help reduce eye strain, headaches and fatigue. Once you step outside, however, they shouldn’t be used, as natural sunlight actually helps regulate your body’s sleep-wake cycle, mood and more. Night-time blue light glasses, though, are designed to block 100% of blue and green light and are meant for use after sunset to help your brain wind down.