I have summarized below [in the attached schematic] the biochemical processes involved in Shaving Bumps formation as per the BREEJ New Hypothesis that Shaving Bumps are Primarily Caused by the Trauma from Shaving
Shaving Bumps are Primarily Caused by the Trauma from Shaving
Ingrown hairs are Caused by Shaving Bumps
Ingrown hairs [more appropriately referred to as entrapped hairs] result when existing shaving bumps block the opening of the hair follicles on the skin forcing the normally growing hairs to grow into the existing bumps [hence the name ‘ingrown hairs’].
It is practically impossible [based on the structure of the Stratum Corneum] for the hair outside the skin [or hair cut at an angle] to curl and grow back into the skin contrary to what is claimed and published by many!
Blacks get more severe bumps due to higher content of MELANIN [the skin pigment]
Melanogenesis induced by irritated Keratinocytes produce additional inflammatory mediators – Cytokines and Reactive Oxygen Species [ROS]
Melanocytes also produce additional inflammatory Cytokines
It is best to shave with a multi-blade razor [causes minimal irritation] and coarse, curly hairs [manifested in all ethnic/racial groups] play no role in shaving bumps formation