7 surprising facts about the penis

Anatomically speaking, the penis is just one part of the male reproductive system. The scrotum, prostate, epididymis, vas deferens, and seminal vesicles make up the rest. But there’s a reason we hear about the penis the most. It's the most prominent external feature and the site of sexual pleasure.

The penis doesn't only provide a window into one's sexual and reproductive health. It can also offer important clues to the health of the rest of the body. Here are some lesser known facts about the penis.

It might not be a bone, but a penis can break. Penile fracture is rare, but it can happen and it can be dangerous to the male anatomy, says Faysal Yafi, MD, a urologist at the University of California, Irvine.

Penile fractures typically occur when an erect penis is thrust into a hard or bony structure during sex. Symptoms of a fracture include immediate loss of erection, pain, swelling, and bruising. If you do believe you have fractured your penis, head to your nearest emergency department or healthcare provider (HCP). Surgery is typically needed to repair the damage to the penis.

Cigarette smoking causes stress to the body, subsequently causing stress to the penis. “The tissue starts dying off,” Dr. Yafi says. “It’s very likely the penis shrinks with smoking.”

Men who smoke about 10 cigarettes a day, or those who have smoked for about 10 years, can experience such shrinkage. One possible reason smoking might cause this side effect? Smoking causes blockage in the small arteries in the penis, which may trigger a weaker erection. If you need another reason to quit smoking: Male smokers are also at greater risk of developing erectile dysfunction.

Circumcision, the removal of the foreskin of the penis, has its advantages and disadvantages. Research has shown that circumcision might lower a man’s risk of prostate cancer, urinary tract infection, and sexually transmitted infections.

Meanwhile, some studies suggest that the foreskin has the most sensation of any part of the penis, which might mean that men with uncircumcised penises have greater stimulation in the tip of the penis. The American Academy of Pediatrics (AAP) has found that the benefits of newborn circumcision generally outweigh the risks, but the benefits aren’t great enough to recommend circumcisions worldwide. Whether or not you circumcise your newborn should be a parent’s choice, AAP recommends.

Sorry, folks, there’s no evidence that eating sweet foods like pineapple will make for better tasting semen. In fact, there’s no proven correlation between diet and the taste of semen at all.

The male ejaculate is made of 96 percent water, 2 percent sperm, while a variety of nutrients make up the remaining 2 percent. “When you think about it this way, not much is going to affect the semen itself, outside of whether someone is dehydrated or not,” Yafi says.

You can’t eat sweet foods to improve semen taste, but you can eat for better sperm health, which is important for fertility. Foods rich in antioxidants like blueberries, walnuts, and leafy greens can improve the quality of a person's sperm. Sperm quality is characterized by three factors: quantity of sperm in the ejaculate, the sperm’s movement, and its structure. Looking for other ways to boost sperm health? Avoid smoking, maintain a healthy weight, and eat a well-balanced diet. 

Nighttime erections occur in healthy men during a normal night’s sleep. On average, a man will experience three to five full erections each night. These erections—or the lack thereof—often help HCPs determine the cause of erectile dysfunction.

HCPs look at three factors to help diagnosis ED:

• The strength of the erection or the amount of blood flow into the penis
• How long the erection lasts
• How frequently spontaneous erections, those not spurred by sexual excitement, occur. 

If you don’t experience nighttime erections or have erections that last fewer than 25 minutes or don’t reach a full erect state, then you might want to talk to your HCP.

Like people, penises come in all shapes and sizes. Some men have a curve or bend in the penis during an erection called Peyronie’s disease. The condition occurs when scar tissue develops in the deeper structures of the penis. The scar tissue often becomes painful and can make sex uncomfortable.

Peyronie’s disease is fairly common and often affects men between the ages of 40 and 60 or older. While the cause is often unknown, it’s not uncommon for the condition to resolve on its own. If the condition doesn’t go away, medication or medical therapies like ultrasound may be recommended. In rare cases, surgery may be needed to correct the issue.