I posted a few messages a while back--a year or several months ago. I had permanently peeling lips after a long bout of a serious and painful illness.
Around the time I was reading the messages here and posting, I was working with an MD who was just as inquisitive as I.
We found a few things off, via testing, like blood Sugar management, celiac, low HCl, and very extreme cortisol fluctuations--cortisol levels naturally curve throughout the day, mine curve but go off the charts at all points with its curve.
I have addressed these issues within myself and my lips stopped peeling. They were normal all these months.
They seem to be chapped again. I am certain it is related to cortisol levels. I believe this because recently, my cortisol has been high again. I was pushing myself physically and with some stress, and then I got wiped out from a bad cold. I recognize some symptoms of high and low cortisol in other ways.
I know it is not the other things that were wrong with me at the time, because I have slipped up with the Celiac diet, and ingested gluten during these past few months. I have gotten other symptoms related to Celiac, but not chapped lips. I also have some residual blood Sugar issues that I am addressing, and have not have had chapped lips.
It is the high cortisol, or extreme fluctuations. My doctor taught me how to address the fluctuations with pregnenalone, for lowering high levels, and licorice root syrup, for low levels. It is not good to mess with pregnenalone on your own. I am very sensitive, so took very tiny amounts, much less than prescribed.
I would recommend going to a naturalistic MD to discuss this and get a 24 hour saliva cortisol test.