I read this 9-year-old (!) post by CheiltisFighter and found a lot of sense in their post. I may just have seborrheic dermatitis, which I may have mistaken for exfoliative cheilities. I have had this for 10-12 years. I have tried several things (leaving alone, lip balms, no-biting, diet changes, doctor visit, etc etc), but none helped.
The white stuff that forms on my lips seems more like a secretion than dying of the top layer of the lip. It seems like I don't have a top layer (epidermal layer) to begin with. My "EC"/SD is not painful, does not cause cracking, bleeding, or swelling. I used to bite my lips (and still do occasionally), and also have been using lip balm since I was a child.
My theory is there is some fungus or weird moldy stuff forming on my lips because of excess moisture. Yupp! All this time I thought this was the result of my lips being too dry, but now it seems it's a result of my lips being kept too moist! I sleep with a thick layer of lip balm on (usually contains coconut oil), which soaks the white stuff and helps me slough them off in the morning after brushing my teeth.
What I've been doing for the past week is applying witch hazel solution to my lips twice a day with a Q-tip. The first three days, the stuff was too hard so I bit it off (I know, I know.) and applied witch hazel. The next few days, I did not have to bite the skin off. I took a towel, wet a section of it with warm water, and rubbed my lips in circular motions to get rid of the flakes (this is "normal lip scrubbing" for those with normal, no-EC/SD lips). This helps take off only the flakes and lets the thinner layer of skin or whatever that forms now to stay on. I then soak with witch hazel. Scrub once a day, witch hazel once or twice a day. I did NOT use lip balm AT ALL during the last week. ESPECIALLY NOT OVERNIGHT since the crappt mold or whatever would probably form again.
It's been one week and my lips are very dry. They are not crusty and building up, but are just very dry. They are somewhat hard. What I have deduced is I am helping my lips learn to repair themselves without the help of moisture, which only provides a temporary layer of goo. Using witch hazel in cream or balm form would be counterproductive, we need something in liquid form that disappears, as CheiltisFighter stated.
Today my lips are very dry, so I put on a lip balm (it was very hard for me not to apply any since I'm a lip balm addict). It's a light argan oil lip balm which does not contain ingredients that wet my lips. I am now going to continue the witch hazel treatment and am going to use lip balms that I previously avoided using because they didn't soak the white stuff (so now the non-wetting balms are helpful).
I don't have a before picture because I never let my lips get to that ugly point (always sloughed the white stuff off) except leave-alone days about 5 or 6 years ago.
I will need to use lipstick soon, so I'll be using liquid lipsticks that dry down completely instead of creamy ones which may just cause more problems.
I will continue updating you on my lip condition. I'll try to answer any questions you have as well!