When someone experiences hard, painful nipples, their first concern may be whether this is evidence of a severe health problem. The good news is that nipple pain is rarely a symptom of cancer or another serious disease. It is normal for nipples to become irritated during certain activities, such as sports. This can usually be resolved with simple remedies or lifestyle changes. Sometimes, it is natural for a nipple to become hard.
Nipples are weird and wonderful things; they go hard when you're turned on and stick out like sore thumbs when you're cold - and sometimes, just go hard for no apparent reason. Only it turns out there is a reason behind the often unpredictable erections bet you've heard that one before , and it's down to a highly specialised type of nerve cell that does nothing else except generate nipple erections. According to the journal of Nature Neuroscience, hard nipples are normally involuntary and are controlled by the sympathetic nervous system, which also coordinates and regulates all our other unconscious bodily functions. The study's co-author Alessando Furlan explained: "We've shown that the sympathetic system consists of many types of neuron that regulate specific functions in the body. Of course, being cold, breastfeeding and sexual arousal can also prompt your nipples to stick out, which might be down to how sensitive the area is, or the smooth muscle cells around the areolae contracting when stimulated. Like this? Come and check us out on Snapchat Discover.
Here's what's going on when your nips stand at attention. You probably don't spend too much time thinking about your nipples—until they demand your attention. Maybe that's when you're working out sans shirt and all of a sudden it's like there's a pair of headlights poking out from your sports bra.
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