As we know, ultraviolet (UV) radiation from the sun is a primary contributor to skin ageing and to certain other skin conditions. However, there have been increasing concerns about the potential skin-related effects of high energy visible (HEV) blue light from personal electronic devices. According to a review article in a prestigious journal on dermatology, (Journal of Cosmetic Dermatology), though short-term exposure to low-energy blue light may prevent and treat some skin diseases, longer-term exposure to high-energy blue light can increase DNA damage, cell and tissue death, skin barrier damage, and possibly photoageing.
Sun is the primary source of blue light in our environment, but digital screens (computers, TVs, and smartphones) also emit blue light – and the connection to increased exposure to these devices and possible signs of ageing are being increasingly explored. As reported, some studies find that blue light generates reactive oxygen species and produces oxidative damage in the skin, an effect similar exposure to UV. But the longer wavelength and lower energy of blue light vs UV light suggests that blue light may penetrate deeper into the skin layers and induce DNA damage and cellular dysfunction. Researchers suggest that this could add to photoageing and other inflammatory skin conditions.
The review article explains, flavins in the skin are the primary photosensitizers for blue light that cause oxidative stress and produce superoxide. Superoxide production mediated by blue light exposure may significantly contribute to skin ageing. Also, blue light can exert negative effects on collagen and elastin in a similar manner following UV exposure, research suggests. Blue light has been shown to induce matrix metalloproteinases in skin cells, for instance, which can degrade collagen. Also, blue light irradiation of human skin forms free radicals and reduces carotenoids in the skin. Exposure to blue light can stimulate melanocytes and contribute to protein complexes that lead to pigmentation changes, including darkening of the skin. Hyperpigmentation associated with exposure to visible light is typically only observed in people with dark skin types.
A study compares the intensity of blue light from personal electronic devices to the sun. In descending order of blue light intensity, the highest intensity came from the sun, then TVs, computer screens, laptops, and smartphones.
The research on the link between exposure to blue light from digital devices and possible ageing is far from conclusive, however, research is underway – irrespective of which, the need for daily skin protection from the sun’s UV exposure – whether direct or indirect through cloud cover, is only reinforced.
It is important to note that despite the negative effects, blue light also serves therapeutic purposes for several skin disorders when administered at small doses.