The prostate is a small gland, roughly the size of a walnut, that sits just below the bladder in people assigned male at birth. Its primary job is producing fluid that mixes with sperm to create semen. Though small, the prostate plays an outsized role in both reproductive health and urinary function, and it’s the source of some of the most common health concerns men face as they age.
Where the Prostate Sits
The prostate is positioned directly below the urinary bladder and in front of the rectum. It wraps around part of the urethra, the tube that carries urine from the bladder out through the penis. This location explains why prostate problems so often affect urination: when the gland swells or grows, it squeezes the urethra and restricts flow. It also explains why doctors can feel the prostate during a rectal exam, since only a thin wall of tissue separates the gland from the rectum.
What the Prostate Does
The prostate’s main function is producing a thin, slightly acidic fluid that makes up about 30% of semen. The remaining volume comes from other glands in the reproductive tract. Prostate fluid contains a mix of components that keep sperm alive and functional: zinc, citric acid, and several enzymes that break down proteins. One of those enzymes liquefies semen after ejaculation, allowing sperm to swim freely.
The fluid also helps neutralize the naturally acidic environment inside the vagina, which would otherwise damage sperm before they could reach an egg. In short, without prostate fluid, sperm would have a much harder time surviving the journey to fertilization.
Size, Growth, and Changes With Age
A healthy adult prostate weighs between 15 and 25 grams, with a volume of about 25 milliliters. During puberty, hormones cause the prostate to grow to its adult size. Then, starting around age 25, the gland begins a second, much slower phase of growth that continues for the rest of a man’s life.
This gradual enlargement is completely normal and happens to nearly everyone. But because the prostate surrounds the urethra, that growth can eventually cause noticeable urinary symptoms. By age 60, a significant number of men experience at least some effects from an enlarged prostate. By age 80, the majority do.
Enlarged Prostate (BPH)
The medical term for a non-cancerous enlarged prostate is benign prostatic hyperplasia, or BPH. It is not cancer and does not increase cancer risk. The symptoms are almost entirely related to urination and range from mildly annoying to seriously disruptive:
- Frequent or urgent need to urinate, especially waking up multiple times at night
- Trouble starting to urinate or a weak, stop-and-start stream
- Dribbling at the end of urination
- Feeling like your bladder isn’t fully empty even after you’ve finished
Less commonly, BPH can lead to urinary tract infections, blood in the urine, or a complete inability to urinate. That last scenario is a medical emergency. Most cases of BPH are managed with lifestyle adjustments or medication, though procedures to reduce prostate tissue are an option when symptoms are severe.
Prostatitis
Prostatitis is inflammation of the prostate, and it can affect men at any age, not just older adults. There are several types, and they feel quite different from one another.
Acute bacterial prostatitis comes on suddenly and hits hard. It causes fever, chills, painful urination, and sometimes difficulty urinating at all. It requires prompt treatment with antibiotics. Chronic bacterial prostatitis is a slower, recurring version. The symptoms overlap (pain while urinating, difficulty with flow) but typically without the fever and chills. It can take longer to resolve.
The most common form, chronic pelvic pain syndrome, causes pain in the lower abdomen, genitals, or the area between the scrotum and rectum. The pain can spread to the lower back and is often accompanied by a frequent urge to urinate. Despite the name, this type is not always caused by a bacterial infection, which makes it harder to treat.
There’s also a form called asymptomatic inflammatory prostatitis, which causes no symptoms at all. It’s typically discovered by accident during tests for something else and generally doesn’t need treatment.
Prostate Cancer
Approximately 13.2% of men will be diagnosed with prostate cancer at some point in their lifetime, making it one of the most common cancers in men. The good news is that most prostate cancers grow slowly. Many men diagnosed with it live for decades without the cancer ever causing serious harm, and some never need active treatment at all.
Prostate cancer often produces no symptoms in its early stages, which is why screening exists. The most common screening tool is a PSA blood test, which measures a protein produced by the prostate. Normal PSA levels rise naturally with age:
- Ages 40 to 50: up to 2.5 ng/mL
- Ages 50 to 60: up to 3.5 ng/mL
- Ages 60 to 70: up to 4.5 ng/mL
- Ages 70 to 80: up to 5.5 ng/mL
A PSA level above these ranges doesn’t automatically mean cancer. BPH, prostatitis, recent physical activity, and even age-related changes can all push PSA higher. An elevated result typically leads to further testing, not an immediate diagnosis. The decision about when to start PSA screening, and whether to screen at all, depends on individual risk factors like family history and race. Black men have a notably higher risk of prostate cancer and may benefit from earlier conversations about screening.
How to Keep Your Prostate Healthy
You can’t prevent age-related prostate growth, but certain habits are associated with better prostate health overall. Regular physical activity, maintaining a healthy weight, and eating a diet rich in vegetables and lower in red meat all appear to lower the risk of prostate problems. Staying well-hydrated but limiting fluids before bed can help manage nighttime urination if early BPH symptoms appear.
Paying attention to urinary changes is the most practical thing you can do. A weaker stream, more frequent trips to the bathroom, or discomfort during urination are all worth mentioning at your next medical visit. These symptoms are common, usually treatable, and rarely a sign of something serious, but catching problems early gives you more options.