The prostate is a small gland, roughly the size of a walnut, that sits just below the bladder and surrounds the tube that carries urine out of the body (the urethra). Only men have one. Its primary job is producing a portion of the fluid that mixes with sperm to create semen, helping nourish and transport sperm during ejaculation. Because of where it sits, wrapped around the urethra, the prostate has an outsized influence on urinary function, especially as men age.
Where the Prostate Sits
The prostate is tucked deep inside the pelvis, directly beneath the bladder and in front of the rectum. Its base connects to the bladder wall, while the narrow end (the apex) points downward. The urethra runs straight through the center of the gland, which is why any swelling or growth in the prostate can squeeze the urethra and interfere with urination. The prostate’s position in front of the rectum is also why doctors can feel it during a rectal exam.
What the Prostate Does
The prostate’s main role is reproductive. It produces a milky, slightly alkaline fluid that makes up roughly 20 to 30 percent of semen volume. This fluid contains enzymes, zinc, and citric acid that help keep sperm alive and mobile after ejaculation. During orgasm, muscles in and around the prostate contract to push this fluid into the urethra, where it mixes with sperm from the testes and fluid from other glands.
The prostate also acts as a valve. The muscles surrounding the gland help control the switch between urination and ejaculation, preventing urine from mixing with semen during sex.
How the Prostate Changes With Age
Unlike most organs, the prostate keeps growing throughout a man’s life. In men aged 40 to 49, the average prostate weighs about 28 grams. By age 60 to 70, that climbs to around 35 grams, and past age 75 it averages over 46 grams. The cause isn’t entirely understood, but shifting levels of sex hormones as men age likely play a role.
This gradual growth is called benign prostatic hyperplasia, or BPH. Because the prostate wraps around the urethra, even modest enlargement can start squeezing the urinary channel. The result is a collection of symptoms most men over 50 will recognize: a weak or interrupted urine stream, difficulty starting urination, the need to urinate more often (especially at night), and the feeling that the bladder hasn’t fully emptied. BPH is not cancer and doesn’t raise cancer risk, but it can significantly affect quality of life.
Common Prostate Problems
Prostatitis
Prostatitis is inflammation of the prostate, and it can affect men at any age. There are several types. Acute bacterial prostatitis comes on suddenly with fever, chills, painful urination, and pelvic pain. It’s caused by a bacterial infection and typically responds to treatment quickly. Chronic bacterial prostatitis develops slowly, produces milder versions of the same symptoms, and can persist for months or years with recurring flare-ups.
The most common form, chronic pelvic pain syndrome, accounts for the majority of prostatitis cases. It causes pain or discomfort lasting three months or more in the area between the scrotum and anus, lower abdomen, lower back, or penis. Pain during or after ejaculation is a hallmark symptom. The exact cause is unclear; it may involve immune system reactions, nerve damage in the pelvic area, or irritation from chemicals in urine rather than an active infection.
Prostate Cancer
Prostate cancer is the most common non-skin cancer in men. It typically grows slowly, and many men with prostate cancer never experience symptoms during their lifetime. When it does produce symptoms, they overlap heavily with BPH: trouble urinating, weak stream, frequent nighttime urination. That overlap is one reason screening matters, since the symptoms alone can’t tell you which condition you’re dealing with.
How Prostate Health Is Checked
Two tools form the foundation of prostate screening. The first is a digital rectal exam, where a doctor inserts a gloved finger into the rectum to feel the prostate’s size, shape, and surface. They’re checking for unusual enlargement, hard spots, or bumps that could signal a problem. The exam takes about 30 seconds and, while uncomfortable, isn’t painful for most men.
The second tool is a PSA blood test, which measures levels of prostate-specific antigen, a protein produced by the prostate. Normal PSA levels rise gradually with age: under 2.5 ng/mL is typical for men in their 40s, while men in their 70s may see levels up to 5.5 ng/mL and still fall within a normal range. Elevated PSA doesn’t automatically mean cancer. Infections, BPH, and even recent physical activity can push levels up. But a high or rapidly rising PSA signals that further testing, such as imaging or a biopsy, may be warranted.
Current guidelines from the U.S. Preventive Services Task Force recommend that men aged 55 to 69 make an individual decision about PSA screening after discussing the benefits and limitations with their doctor. For men 70 and older, routine PSA screening is generally not recommended because the risks of follow-up procedures often outweigh the benefits. Men with a family history of prostate cancer or Black men, who face higher prostate cancer rates, may want to start the conversation earlier, though no separate formal recommendation exists for these groups yet.
Diet and Prostate Health
Certain dietary patterns show links to prostate health, though no single food is a magic bullet. Lycopene, the compound that gives tomatoes their red color, has the most consistent evidence. A large meta-analysis found that men with higher lycopene intake, whether from food or measured in their blood, had about a 12 percent lower risk of prostate cancer compared to men with the lowest levels. Cooked tomatoes, watermelon, and pink grapefruit are the richest sources.
Soy foods also show promise. A meta-analysis found that regular consumption of nonfermented soy products like tofu and soy milk was significantly associated with lower prostate cancer risk. Green tea has shown modest benefits in smaller trials, with men drinking it regularly showing lower PSA levels and slower progression of precancerous prostate changes.
On the other side, high calcium intake, particularly from dairy, has been linked to increased risk of advanced prostate cancer in some studies. That doesn’t mean you need to eliminate dairy, but men who consume large amounts may want to be aware of the association. Selenium supplements, once thought protective, showed no benefit in a major trial and actually increased the risk of high-grade prostate cancer in men who already had adequate selenium levels. The takeaway: getting nutrients from food rather than supplements is generally the safer approach for prostate health.