[epgui]

Yes, constantly biting your lip (I’m talking about injuring the tissue, not just nibbling) will increase your risk of oral cancer too.

It’s not something most people do super often, so I’m not sure if we’d even have a risk measurement for that. In almost all cases of accidental biting risk is basically nil / negligible… But theoretically nonzero.

A reference (somewhat taken at random) for more explanations of the general concept: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2803035/

It’s a well-established principle, and is one of the main reasons why smoking anything in general will cause lung cancer, why hepatitis frequently leads to liver cancer, why IBD frequently leads to bowel cancer, why alcohol consumption causes oral cancer, etc.