My newborn nephew was born as scheduled and by all accounts healthy. However, after a few days, it became apparent that he had jaundice and his liver was not able to process/break-down the bilirubin in the blood. Apparently, this is actually quite common for newborns since their livers are not fully formed, and they have more red-blood cells than adults do or whatever... (sorry, I'm not a health physician -- this is just my understanding from my sister-in-law). There was the possibility that if the jaundice didn't go away within a short period of time (with the help of special formula), that my nephew would have to go under phototherapy (under intense blue lights). See image below:
How does phototherapy's blue lights break down bilirubin?
Fortunately, my nephew's jaundice cleared up on it's own, but I've been curious how phototheraphy works.