Blue Light - Dangerous or Therapeutic?
Skincare products with “blue light protection” claims have significantly increased during the COVID-19 pandemic, due to the sudden increase in exposure to electronic devices for long periods of time. Nevertheless, more home-therapies have been marketed utilising blue light to help improve the skin . This contradiction in claims has everyone wondering: is blue light dangerous or therapeutic?
Blue light is part of the visible spectrum of light with a wavelength between 400-500nm. It has a short wavelength with high energy, which allows a deeper penetration into the skin than UV-A, UV-B and UV-C radiation and can be often referred to as High Energy Visible (HEV) light . The main source is sunlight; however, now-a-days more electronic devices are made using LED (light emitting diode) interfaces which have become a big source of exposure to blue light when indoors .
To understand the impact of blue light on the skin, years of research have been carried out and it has become clear that the intensity, specific wavelength used, and time of exposure can vary the results significantly, and here is why.
Many studies evaluating the impact of long-term exposure to blue light on the skin have demonstrated that it can penetrate to a depth of 0.07-1mm, concentrating mainly in the dermis . This is where most of the collagen and elastin are found and, under the presence of blue light, these can get damaged through the increased production of free radicals, leading to premature signs of ageing, such as wrinkles or skin laxity . Another common occurrence is hyperpigmentation, especially of Fitzpatrick skin type III and above, as it activates a receptor in the protein producing melanin, leading to higher levels of deposited melanin exhibited as darker patches .
Despite the undesired effects, blue light can be used to treat inflammatory skin diseases . This is because short term, controlled exposure does not cause damage, instead it can be an effective treatment for some types of acne as it kills bacteria responsible for the inflammatory response that causes swollen acne bumps. Therefore, using blue light medical devices, alongside adequate skincare products is an effective way to control and reduce acne, but is not necessary for healthy skin . Additionally, this treatment is being studied for its effects against psoriasis, eczema, and atopic dermatitis symptoms; nonetheless, more evidence is needed for the results to be conclusive.
All in all, controlled use of blue light can be therapeutic when treating inflammatory skin diseases, but it is always recommended to ask a professional before carrying out home-treatments. Moreover, uncontrolled exposure does exhibit dangers as it results in premature skin ageing and hyperpigmentation so it is important to use protective skincare products; particularly ones containing iron oxides, which can act as a barrier for blue light. Botanical extracts, antioxidants and vitamin serums should also be used alongside to help repair skin damage. Finally, limiting screen time or using blue light screen-protectors on electronic devices are useful preventative measures to slow down the process .
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