Underarm_hair
Underarm hair
Human body hair
Underarm hair, also known as axillary hair or armpit hair, is the hair in the underarm area (axilla).
Underarm hair | |
---|---|
Details | |
Identifiers | |
Latin | hirci |
TA98 | A16.0.00.021 |
TA2 | 7061 |
FMA | 70756 |
Anatomical terminology |
Underarm or axillary hair goes through four stages of development, driven by weak androgens produced by the adrenal in males and females during adrenarche, and testosterone from the testicle in males during puberty.[2]
The importance of human underarm hair is unclear. It may naturally wick sweat or other moisture away from the skin, aiding ventilation. Colonization by odor-producing bacteria is thereby transferred away from the skin (see skin flora).[3]
- Male axilla
- Female axilla
- Axillia of a pubescent male, note the short, stray hairs characteristic of this stage (Wolfsdorf 2)
Reducing friction
Armpit hair prevents skin-to-skin contact during activities that involve arm motion, such as running and walking. The same applies to pubic hair.[4][better source needed]
Spreading pheromones
The armpits release odor-containing pheromones, a naturally produced chemical that plays an important role in sexual attraction. Armpit hair traps odor, making the pheromones even stronger. A study in 2018 including 96 heterosexual couples found that there were stress-relieving benefits to smelling a romantic partner's natural scent.[5]
Effect on odor
А 2012 study on the impact of hair removal on odor found that shaved armpits were rated the same as unshaved armpits.[6]
Chemical absorption
A 2017 study on chemical absorption from deodorants as a result of hair removal showed an increase in chemical absorption from .01% to .06% where skin has been damaged by recent shaving.[7]
A 2003 study on aluminum antiperspirant usage and the age of breast cancer onset tentatively concluded that “underarm shaving with antiperspirant/deodorant use may play a role in breast cancer.”[8]
- Pineau, Jean-Claude (2020). "Age estimation of teenage boys during puberty". American Journal of Forensic Medicine and Pathology. 41 (3). Williams & Wilkins: 188–193. doi:10.1097/PAF.0000000000000573. PMID 32796206. S2CID 221257760.
- Auchus RJ, Rainey WE (March 2004). "Adrenarche - physiology, biochemistry and human disease". Clinical Endocrinology. 60 (3): 288–296. doi:10.1046/j.1365-2265.2003.01858.x. PMID 15008992.
- Paye M, Maibach HI, Barel AO (2009). Handbook of cosmetic science and technology (3 ed.). Informa Health Care. p. 703. ISBN 978-1-4200-6963-1.
- "MRSA superbug? Part 1". PsycEXTRA Dataset. 2007. doi:10.1037/e721542007-001. Retrieved 12 July 2022.
- Klotz K, Weistenhöfer W, Neff F, Hartwig A, van Thriel C, Drexler H (September 2017). "The Health Effects of Aluminum Exposure". Deutsches Ärzteblatt International. 114 (39): 653–659. doi:10.3238/arztebl.2017.0653. PMC 5651828. PMID 29034866.
- Media related to Underarm hair at Wikimedia Commons