Highlighting Nuances of Blue Light Phototherapy: Mechanisms and Safety Considerations

The document reviews the mechanisms and safety considerations of blue light phototherapy, highlighting its effects on skin cells and tissues. Studies involving healthy subjects (n=12, n=8, n=20) showed that blue light (390-460 nm) at doses up to 100 J/cm² did not cause significant DNA damage, apoptosis, or photodamage, as indicated by stable p53 expression and absence of "sunburn cells." Additionally, blue light did not disrupt collagen or elastin fibers, nor did it significantly alter immune cell populations such as Langerhans cells. These findings suggest that blue light phototherapy is safe for short-term dermatological use.