Does a Healthy Penis Smell Bad—And What About Semen?

Chances are, you've experienced foul body odor smell at some point in your life. It's normal for the human body to produce certain odors—between bacteria, glands, and chemicals—something is bound to create a smell. But what about the genitals? If you catch a whiff of a bad odor, you may be wondering if it's normal. So what should a penis smell like—and is there a "normal" penis smell?

Detecting Body Odors

Yes and no, said Mike Bohl, MD, MPH physician, and director of medical content at Ro. "Certain parts of the body that are covered in skin don't feel like they smell," Dr. Bohl said. "For instance, if you smell your forearm right now, it probably doesn't have an odor that you can detect unless you recently used soap, cologne, or perfume."

The same goes for the penis—at least, a well-cleaned penis following a shower. But sometimes, things can get smelly. "There are a couple of reasons a penis can pick up an odor over the course of the day," Dr. Bohl said.

Sweat

First, sweat glands. "Most of the body is covered in sweat glands called eccrine glands, which secrete water and salt and are good for cooling off the body," Dr. Bohl explained. "But there's another kind of sweat gland called an apocrine gland, which are larger, secrete additional compounds like proteins and fats, and they are largely responsible for body odor."

Apocrine glands are only found in certain parts of the body, such as the armpits and—you guessed it—the groin, according to the National Cancer Institute. "For this reason, the penis may actually smell more like an armpit than like your forearm after a long day of sweating," Dr. Bohl said.

Lack of Ventilation

Another reason the penis might smell a little funky is because of where it spends most of the day. "It's confined in underwear, which is further confined in pants, and it probably doesn't move around that much," Dr. Bohl said. "There is less fresh air in the area and it is also more difficult for sweat and dead skin cells to fall away—it all basically stays pressed up against the penis."

If you think about it, this is kind of like what we do to our feet, keeping them confined in socks and shoes all day—and it's common for feet to smell. To help with the genital smell, try to wear underwear that is made with a breathable fabric, like cotton, and be sure to wash your underwear after wearing it.

Poor Penis Hygiene

Finally, if underwear isn't clean and some residual urine is in the mix as well, this can cause a stench. This one doesn't really need much explanation, right?

Health Problems That Cause Smells

If a penis smells a little like an armpit or a foot at the end of the day, it's probably not a cause for concern, Dr. Bohl suggested. Soaping up in the shower should get rid of the funk since the soap will remove the bacteria from your body.

But if the penis has a particularly bad odor, or it can't simply be washed away, this might indicate a health problem.

Sexually Transmitted Infection (STIs)

If you are experiencing discharge and it smells, you could have a sexually transmitted infection (STI). According to the Centers for Disease Control and Prevention (CDC), a symptom of herpes can include smelly discharge from the genitals. Although, most people with genital herpes don't experience any symptoms.

"Descriptions of what exactly the odor smells like vary from mushrooms to ammonia," Dr. Bohl said. "But in general, having any sort of discharge from the penis should prompt you to see a healthcare provider."

There are a couple of STIs that cause discharge from the penis. Chlamydia is one of them. Additionally, gonorrhea can cause discharge from the penis that is green, white, or yellow in color.

Balanitis

Another possible cause of a smelly penis is a buildup of smegma—a cheese-like substance consisting of naturally-secreted oils, dead skin cells, and moisture that collects under the foreskin—according to an article in the journal Investigative and Clinical Urology. Smegma is more common in people who are uncircumcised, Dr. Bohl said, because it can get trapped under the foreskin. Dr. Bohl advised careful washing of the penis in the shower, and if there is any smegma buildup, it should be wiped away.

If the penis isn't adequately cleaned, or if there is residual smegma, you can get a condition called balanitis, which is inflammation of the head of the penis, according to MedlinePlus. "Balanitis can be very uncomfortable and may also cause the penis to smell," Dr. Bohl added. Balanitis can also be caused by infection—often fungal, sometimes bacterial—harsh soaps, uncontrolled diabetes, or other diseases.

Treatment for balanitis can vary, depending on the cause. But it can include antibiotics, a steroid cream, or an antifungal cream. Severe cases may result in circumcision.

Fournier Gangrene

This rare form of gangrene involves an infection of the scrotum, penis, or perineum, according to the National Organization for Rare Disorders (NORD). This infection causes the tissue on these organs to die and fall off which can lead to a foul smell. Typically, Fournier gangrene is secondary to other infections, trauma, surgery, or urinary tract infections (UTIs).

What Semen Should Smell Like

Okay, so what about semen? The smell situation is a little different here. Because semen is a bodily fluid, it does have a characteristic smell. "Semen is slightly alkaline—the opposite of acidic—on the pH scale, and many people consider semen to smell like bleach or ammonia, which are both alkaline substances," Dr. Bohl said.

So while it's normal for semen to have an odor, a change in scent—like if it becomes foul—can be a clue to a health issue.

"If the urethra—the tube that urine and semen travel through—is filled with discharge from an infection like chlamydia or gonorrhea, that discharge can mix with the semen, giving it an odor, and possibly a slightly different color as well," Dr. Bohl explained.

You might have heard that eating certain foods can change the smell of semen. While Dr. Bohl said this hypothesis isn't backed up by science, it's definitely possible that certain foods can affect semen's smell.

A Quick Review

The reason your penis has a funky smell could be due to sweat, lack of ventilation, poor hygiene, STI, or smegma buildup. It's important to practice good hygiene and use soap to get rid of any bacteria that could cause an odor.

If the smell persists, you may need to contact a healthcare provider to find out if you have an underlying health problem.