Question: Why do Pinays [Filipino women] have dark underarms?
Do they really? Is this observation supportable by sufficient data? The Filipino finds the premise of your question extremely interesting and he'll probably be more observant in this department moving forward. ;-)
In any case, without regard to race, according to The Beauty Brains ("Real Scientists Answer Your Beauty Questions"), the top five causes of darkened armpits are:
1) Shaving - "If your hairs are slightly darker than your skin color, they can give the appearance that your skin has a dark stain when it`s really just sub-surface hair."
2) Buildup of dead skin cells "trapped in microscopic 'hills and valleys' on your skin."
3) Antiperspirant and deodorant usage - "In theory, some ingredients in these products (perhaps the fragrance) could be reacting with the skin to cause discoloration. Practically speaking this seems unlikely but many people do claim that when they stop using APDs, the darkness goes away."
4) Acanthosis nigricans - "This [medical] condition causes light-brown-to-black markings on the neck, under the arms, or in the groin. It can be related to insulin production or to a glandular disorder and it typically occurs in people who are overweight."
5) Hyper pigmentation - "This condition causes your skin to produce excess melanin pigment."
If The Filipino has to hazard a guess, of the five theories above, he will submit that despite the article saying it seems unlikely, Cause No. 3 as discussed is the real culprit to blame for the darker armpits of Pinays (assuming of course that the premise of your question is true). Why? Because of the high humidity levels in the Philippines, Filipinos, men or women but especially women, wouldn't be caught dead with wet, or worse, smelly armpits. So what do they do? Well, what would you do? Load up on antiperspirants and deodorants, of course!
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