Cheilitis could be from B2 deficiency. Freddd says it could be from folate deficiency. Based on what dbkita said about B2 increasing MTHFR, with either B2 or folate deficiency as a cause of cheilitis, B2 causing cheilitis seems paradoxical. Unless there's another cause.
Yes indeed, paradoxical seeming. Makes the answers interesting as the paradox has to be an illusion caused by an incomplete and/or faulty explanation.
The reason I said that it appears to be an accelerator, destructively so, is because it not only causes severe epithelial problems, cheilitis, skin infections (immune problems, terribly severe IBS as well as, and the most severe lack of potassium I have ever had with the most persistent severe low potassium responses. It somehow has to cause ALL those problems and likely more. In 2 weeks I had noticeable worsening of my CNS problems. The gains go away so fast and they are so difficult to gain.