The main risk factors for prostate cancer

Prostate cancer develops when cells in the prostate gland begin to grow abnormally. Doctors do not yet fully understand why this happens in some men and not others, but research has identified several factors that raise the risk. The most important ones are age, family history, and race—none of which you can change. Other factors like diet and obesity may play a role, though the evidence is less clear.

No single cause leads to prostate cancer. A man might have multiple risk factors and never develop the disease, while another man with few risk factors might be diagnosed. This unpredictability is why screening and early detection matter: catching the cancer before symptoms appear often means better outcomes.

Key Takeaways

  • Age is the strongest risk factor—prostate cancer is rare before age 50 and becomes more common as men get older.
  • Men with a father, brother, or son who had prostate cancer face higher risk, especially if the relative was diagnosed before age 65.
  • Black men develop prostate cancer more often and at younger ages than men of other races, for reasons that are not fully understood.
  • A high-fat diet, obesity, and smoking may increase risk, though the connection is weaker than age or family history.
  • Having a risk factor does not mean a man will develop prostate cancer—many men with risk factors never do.

Age and prostate cancer risk

Age is the strongest predictor of prostate cancer. The disease is uncommon in men under 50, but the risk rises steadily after that. By age 70, roughly one in seven men will receive a prostate cancer diagnosis at some point in their life. By age 80, the number climbs to about one in five.

This does not mean all older men will develop prostate cancer—many will not. But the longer a man lives, the more time his prostate cells have to develop abnormalities. Doctors consider age when deciding whether to discuss screening with a patient, since younger men are less likely to benefit from early detection.

Family history and inherited risk

Men whose father, brother, or son had prostate cancer face higher risk than men with no family history. The risk is even higher if a relative was diagnosed before age 65, or if multiple family members were affected. Having one relative with prostate cancer roughly doubles a man's risk; having two or more relatives can increase it further.

Some families carry inherited genetic mutations that significantly raise prostate cancer risk. The most studied mutations are in genes called BRCA1 and BRCA2, which also increase breast cancer risk in women. Genetic testing can identify these mutations in some families, though most men with prostate cancer do not carry them. If prostate cancer runs in your family, discussing screening and genetic testing with your doctor can help you understand your personal risk.

Race and ethnicity

Black men develop prostate cancer at higher rates and at younger ages than men of other racial and ethnic backgrounds. They are also more likely to be diagnosed with advanced cancer and to die from the disease. The reasons for these differences are not fully clear—they likely involve a combination of genetic factors, differences in healthcare access, and social factors that affect health overall.

Because of these differences, medical organizations recommend that Black men and men with a family history of prostate cancer discuss screening starting at age 40, rather than age 50 as recommended for other men. This earlier conversation gives men a chance to make informed decisions about whether screening is right for them.

Diet, weight, and lifestyle factors

Some research suggests that diet and weight may influence prostate cancer risk, though the evidence is less definitive than it is for age or family history. A few studies have linked high-fat diets—particularly diets high in red meat and dairy—to increased risk. Obesity has also been associated with higher risk in some studies, especially for aggressive forms of the disease.

Smoking and physical inactivity have been studied as possible risk factors, with mixed results. The strongest evidence supports maintaining a healthy weight and eating a diet rich in vegetables and fruits, which may lower risk. However, these lifestyle changes are beneficial for overall health regardless of their effect on prostate cancer specifically.

Hormones and prostate cancer

Testosterone, the male hormone, plays a role in prostate cancer development. The prostate needs testosterone to function normally, and prostate cancer cells often depend on it to grow. This is why some prostate cancer treatments work by lowering testosterone levels or blocking its effects. However, having high testosterone levels does not directly cause prostate cancer—the relationship is more complex than that.

Researchers continue to study how hormones, genetics, and inflammation in the prostate all interact to create conditions where cancer can develop. Understanding these mechanisms may eventually lead to better ways to prevent or treat the disease.

What does not cause prostate cancer

Several things that men sometimes worry about do not cause prostate cancer. Sexual activity, masturbation, and vasectomy have all been studied and do not increase risk. Benign prostatic hyperplasia (BPH)—an enlarged prostate that causes urinary symptoms—is not cancer and does not turn into cancer, though both conditions become more common with age.

Prostate infections and inflammation may raise risk slightly in some studies, but the evidence is weak. A single infection does not cause cancer. If you have concerns about something you have read or heard, your doctor can clarify what the research actually shows.

Frequently Asked Questions

If my father had prostate cancer, will I definitely get it?

No. Having a family history raises your risk, but many men with a family history never develop prostate cancer. Your risk depends on how many relatives were affected, how old they were when diagnosed, and other factors like your age and race. Talk with your doctor about screening to catch cancer early if it does develop.

Can prostate cancer be prevented?

There is no proven way to prevent prostate cancer entirely. Maintaining a healthy weight, eating a diet rich in vegetables, and staying physically active may lower risk slightly. For men at very high risk due to family history or genetics, some medications have been studied as prevention, but they are not routinely recommended.

Does a high PSA level mean I have prostate cancer?

No. PSA (prostate-specific antigen) is a protein made by the prostate, and elevated levels can signal cancer—but they can also result from infection, inflammation, or benign enlargement. A high PSA level means further testing is needed, not that cancer is present. Your doctor will discuss what the result means for you.

At what age should I start thinking about prostate cancer screening?

Most men should discuss screening with their doctor around age 50. Black men and men with a family history of prostate cancer should have this conversation at age 40. Men at very high risk due to multiple family members with early-onset cancer may discuss it even earlier. Screening is a choice, not a requirement.

If I have multiple risk factors, does that mean I will get prostate cancer?

Having multiple risk factors raises your chances, but it does not may provide you will develop cancer. Many men with several risk factors live their entire lives without prostate cancer. Risk factors help doctors and patients make informed decisions about screening and monitoring, but they are not predictions for any individual man.