What is blue light?
Blue light is a portion of the visible light spectrum (380 to 500 nanometers) contained in sunlight, it is also given off by indoor lighting and common electronic devices, such as computer screens and smartphones.
Blue light penetrates deeper into the skin than UV light but fortunately is not associated with the development of skin cancer.
Most of the blue light people are exposed to comes from the sun. The amount of blue light emitted by devices is “only a fraction” of that given off by the sun, but the problem is that we are constantly spending time on and carrying around these devices and keeping them close to our face and head.
Blue light and your skin
Research shows blue light from electronic devices can lead to changes in your skin cells, including cell shrinkage and death. These speed up the ageing process. Even exposures as short as 60 minutes can trigger these changes.
Too much blue light could also lead to pigmentation. One study linked blue light exposure to more swelling, redness, and pigment changes in people with darker skin.
Although it can negatively impact your skin when used in certain ways, blue light also has healing properties. In one study, a blue light device was used to treat a patch of psoriasis in people with mild to moderate plaque psoriasis. This was done for 4 weeks and helped ease redness and shrink the patch’s size. There were no serious side effects.
It’s also been used to treat mild to moderate acne. A study found blue light lowered the number of blackheads, whiteheads, and other acne after 7 days of treatment.
Actinic keratosis is scaly bumps that show up on the face, ears, lips, hands and other areas of skin exposed to the sun. They sometimes grow into skin cancer. Blue light helps lower the number of these precancerous patches, treating large areas of skin with few side effects.
Blue light is also part of photodynamic therapy. It’s a treatment that uses certain kinds of light to activate a class of drugs -- called photosensitizing agents -- to kill cancer cells. It can be as effective as surgery and radiation in treating certain kinds of cancers. Photodynamic therapy also has fewer side effects.