Do you think you know everything there is to know about your penis? I bet you've got a lot to learn about the male reproductive organ, but don’t take my word for it. Here are five things you most likely did not know about your penis.

1. That smoking habit could be causing your penis to get shorter. Maybe you thought age was having a detrimental effect on your penis, but it might just be that cigarette or cigar you light up every night. Smoking reduces blood flow to the penis and erect penis size is all about blood flow. With less blood to pump up the vessels that cause an erection, your penis could measure up to one cm shorter with prolonged smoking than it did before you started smoking.
2. Flaccid penis size is not always indicative of erection size. There are two types of men in the world – the grower and the shower. While many men think this is just a Hollywood trick to help men with smaller penises feel better about themselves, that’s not the case. Some men have small flaccid penises that grow exponentially when blood flow to the penis increases. Not only does the penis grow in length, but also in width. Other men, however, have very little growth when blood flow increases. 
3. Time stands still for women when having sex. While this may not seem to be a penis fact – it is. While men are worrying about performing well, having the biggest, best penis and premature ejaculation – time is standing still for women. Despite the fact that the average time of intercourse is just short of three minutes, women think it is closer to six minutes. So, stop worrying about your penis and start enjoying those three minutes. 
4. Your penis has nothing to do with sperm production, but your face may have everything to do with it. According to a Spanish study, women who were asked to choose the best looking men among a selection of men chose men with the healthiest sperm. 
5. Your brain has nothing to do with ejaculation. Women love to joke about men having only enough blood to power the brain or the penis, but it appears there is another body part that needs to be included in the joke. When it comes time for ejaculation, it is not the brain that gives the penis the go ahead, it's the spinal cord.