* Hormones: The hormones responsible for this change are androgens, like testosterone. While testosterone is often thought of as a "male" hormone, both males and females produce it, just in different amounts. During puberty, the adrenal glands (and ovaries in females) start producing more androgens.
* Hair Follicles: These hormones stimulate hair follicles in the armpits (and pubic area) to start growing thicker, darker hair.
* Function: The exact function is still debated, but theories include:
* Reducing friction: Armpit hair may reduce skin-on-skin friction during movement.
* Sweat and scent dispersal: Hair can help wick away sweat, potentially aiding in cooling and spreading scent.
* Signaling maturity: The development of body hair signals sexual maturity.
* Social and Cultural factors: Whether someone chooses to remove their armpit hair is a personal decision influenced by societal norms, culture, and individual preferences. There is no medical reason to remove it.