The only sure reason that nipples harden is that it facilitates breastfeeding. When something hits the roof of a baby's mouth, the baby's suckling reflex is activated and it will latch onto the breast for feeding time. But men's nipples harden too. And both sex's nipples harden when aroused and cold, which doesn't fit with the whole breastfeeding thing. So what's the deal? Get as many details as we know in the video below.
Why Do Nipples Get Hard?
There are a few reasons.
Are Men And Women's Nipples Different?
They sure are treated differently.
Written by Curiosity Staff October 3, 2016
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