Blue Light

Theoretically, blue-light-blocking glasses are supposed to help regulate your circadian rhythm. Claims have been made to reduce eye strain while using digital devices, especially in the evenings. In the past couple of years, it has been highly marketed for consumers. But does it truly have an effect, or is it just a marketing scheme?

In a study performed with over 100 participants, there was no significant difference in eye fatigue or improvement in eye-straining. There were also no observed differences in sleep quality. All the selling points of manufacturers of blue-light-blocking glasses are not supported by scientific evidence.

So why has there been such an interest in the effects of blue light? Blue light is the highest energy of visible light with the shortest wavelength. Sources of blue light include the sun, digital screens, LEDs, and fluorescent lightings. The amount of blue light can also profoundly affect our skin (look into blue light makeup, yes, it is a real thing). In high amounts, blue light emission on our skin can activate reactive oxygen species. This can be different from UV light as the blue light emission effect on skin pigmentation correlates more with opsin actions, a group of proteins that induce hyperpigmentation.

On the flip side, there have been some benefits to blue light emission as well. As part of photodynamic therapy, small doses of blue light emission have benefited those with actinic keratosis, Vulgaris psoriasis, eczema, acne vulgaris, and photorejuvenation. So before we altogether remove blue light and the question marks around it, it might not just be a marketing scheme, afterall. For your skin, at least.

Lawrenson, J. G., Hull, C. C., & Downie, L. E. (2017). The effect of blue-light blocking spectacle lenses on visual performance, macular health and the sleep-wake cycle: A systematic review of the literature. Ophthalmic and Physiological Optics, 37(6), 644–654. https://doi.org/10.1111/opo.12406

 

Coats, J. G., Maktabi, B., Abou‐Dahech, M. S., & Baki, G. (2021). Blue Light Protection, Part I—Effects of blue light on the skin. Journal of Cosmetic Dermatology, 20(3), 714–717. https://doi.org/10.1111/jocd.13837