Possible causes of prostate cancer

Although we do not know what causes prostate cancer, certain risk factors may increase the chances of developing it.

  • Age - the risk of prostate cancer increases as men get older. It is more common in men over 70 and much less likely to happen in men younger than 50.
  • Ethnicity – black men have a much higher risk of developing prostate cancer and usually at a younger age. Prostate Cancer UK have an information pack for black men 45 and over who are worried about risk.
  • Family history – in a small number of men prostate cancer may be due to a possible family link (inherited). This is more likely when there are more men in the family with prostate cancer, the more closely related they are, and younger they were when diagnosed.
  • Body weight and diet – being very overweight (obese) may increase the risk of having a more advanced prostate cancer. A diet high in animal fats may increase the risk of prostate cancer.

If you are worried about your risk of prostate cancer talk to your GP about it.

Risk factors and causes

Doctors do not know the exact causes of prostate cancer. But there are risk factors that can increase a man’s chance of developing it. Having one or more risk factors does not mean a man will get prostate cancer. Having no risk factors does not mean a man will not develop prostate cancer. Different risk factors may affect the risk of getting prostate cancer.


Age

This is the strongest risk factor for prostate cancer. Men aged under 50 have a much lower risk of prostate cancer, although they can still develop it. The risk increases as men get older. More than half of all prostate cancers diagnosed in the UK are in men aged 70 and over.


Ethnicity

Black men have a much higher risk of developing prostate cancer than white men. The reason for this is not clear, but it may be due to genetic factors. Black men are also usually diagnosed with prostate cancer at a younger age.

Prostate Cancer UK provide an information pack for black men aged 45 and over who are concerned about their risk. It gives advice on talking to your GP about your risk of prostate cancer, to help you to decide whether to have tests.

Asian men have a lower risk of developing prostate cancer. The reason for this is unknown.


Family history

Most men who get prostate cancer do not have a family history of it. Getting older is much more likely to be the significant risk factor.

But occasionally there may be a possible family link (inherited). Certain things make this more likely. For example, the more men in a family that have prostate cancer, the younger they were when diagnosed and the more closely related they are.

A man’s risk of developing prostate cancer is higher if they have:

  • either a father or brother who had prostate cancer – the risk is greatly increased if they were diagnosed under the age of 60
  • 2 or more close relatives on the same side of the family who had prostate cancer – close relatives include a father, brother, grandfather, half-brother, and an uncle
  • certain inherited cancer gene changes (mutations).

We inherit our genes from our parents. Doctors think 5% to 10% of prostate cancers are linked to inherited gene changes (mutations). But they do not think there is a specific prostate cancer gene. It is thought that changes in a few genes are involved.

In a small number of men, prostate cancer may be linked to changes in the breast and ovarian cancer genes BRCA1 and BRCA2. Men with the BRCA2 gene mutation may have up to a 5 times higher risk of prostate cancer compared with the general population. The BRCA1 gene may also increase risk, but this is not as clear. Prostate cancer risk is also higher in men with Lynch syndrome, also known as hereditary non-polyposis colorectal cancer (HNPCC).

Talk to your GP if you have a family history of cancer and are concerned about your prostate cancer risk. We have more information about family history and cancer.


Body weight and diet

Being very overweight (obese) may increase the risk of having a more advanced prostate cancer. It may also increase the risk of having a fast-growing (high grade) type of prostate cancer.

A diet high in animal fats may increase the risk of prostate cancer. This includes foods like red meat (such as beef, lamb, and pork) and high-fat dairy products (such as butter, full-fat milk, cheese, and cream).

A healthy, balanced diet is better for your general health. For most people, this includes:

  • foods high in fibre (such as wholemeal bread, brown rice, oats, beans, and lentils)
  • lots of fruit and vegetables
  • less red meat and less processed meat (such as sausages, burgers, bacon, and ham)
  • less fat and less sugar.

Eating a balanced diet and doing regular physical activity keeps you to a healthy weight. This may reduce your risk of certain types of cancers and other conditions, such as heart disease and diabetes.

How diet can help reduce your risk of cancer

Macmillan Specialist Dietician Helen Kennedy explains how a healthy diet can reduce your risk of cancer and help if you're having treatment.

About our cancer information videos

How diet can help reduce your risk of cancer

Macmillan Specialist Dietician Helen Kennedy explains how a healthy diet can reduce your risk of cancer and help if you're having treatment.

About our cancer information videos

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