Does blue light damage skin?

If you have ever used a phone or a computer you may have thought what the effect of blue light – the predominant light shining from our favourite screens – could be doing to your skin.

Capitalising on this, some sunscreen manufacturers have even started claiming their sunscreen protects against the damage the blue light from your device causes your skin. Is this legit? Does blue light damage skin and, if it does, do you need a special sunscreen 24/7 to protect yourself from it? Blue light refers to visible light with a wavelength of 390-460 nm (UVA – the ‘aging’ part of sunlight – is 340-400 nm). The wavelength ranges are very close to each other so can blue light damage skin and lead to photoaging?

Kleinpenning et al (2009) – my Dutch colleagues in Nijmegen – did a study looking at the clinical and histological effects of blue light on normal skin. (histology refers to what the skin looks like when a skin sample is removed from a person’s skin and examined at high magnification under a microscope.) They had 8 young volunteers (age range 19-24) who had part of their bum skin treated with blue light every day for 5 days. Biopsies were taken of the treated area and normal skin on days 2, 3, 5 and 14 days after the last treatment. They did not find that the blue light caused DNA damage or any histological signs of photoaging compared to untreated skin.

This study only looked at short-term effects of blue light on non-facial skin in a small group of subjects. What about long term effects? To my knowledge, that has not been studied on human facial skin. What I would say is the amount of irradiation coming from our screens is so low that even over time it is probably not going to substantially effect the appearance of the skin.