I’ve read in many instances here that sebum does not cause hair loss. While I believe this, a small part of me has some doubts. Is there any definitive proof you can convey to us here?
What sort of proof are you looking for? Sebum is an oily substance secreted by the sebaceous glands. We all have sebaceous glands and we all secrete sebum. Sebaceous glands secrete the oil to give your hair the healthy shine, coating and protecting it from the environment so your hair does not get brittle and break off. Sometimes excess sebum can cause oily skin/hair. You can treat this by washing your hair with shampoos that address oily hair. If you do not wash your hair and let sebum build up you can have bacteria growth that causes a foul smell or even clogs up the pores to cause pimples and cysts. But this will still not cause hair loss, just poor hygiene. If sebum caused hair loss, there would be many more balding women out there.
Hair loss in men is caused by genetics 99% of the time. It occurs in specific patterns, thus the term “male pattern baldness”. Its not called sebum-baldness.