Causes and prevention of prostate cancer

The cause of prostate cancer is unknown at present. But there are things called risk factors that can increase your chance of getting the disease.
Risk factors for prostate cancer include:
  • Age: Your risk increases as you get older. Most men diagnosed with prostate cancer are aged over 50 years.
  • Family history: Men whose brother or father developed prostate cancer at a young age have an increased risk.
  • Race: African-American and African-Caribbean men are more at risk than other ethnic groups.
  • Diet: Men who eat a lot of red meat and high-fat dairy products and not enough green vegetables may have a slightly higher chance of getting prostate cancer.


Living a healthy lifestyle and eating a healthy, balanced diet, which includes a broad variety of foods, including lots of fresh fruit and vegetables, is known to help lower your risk of getting cancer generally. A healthy lifestyle and diet might help to reduce your prostate cancer risk too, although more research needs to be done into lifestyle and prostate cancer risk.  You can read more on how to reduce your risk of cancer here.
The EPIC STUDY (the largest study ever undertaken looking at diet and health and the incidence of cancer across ten European countries) found no relationship between fruit and vegetable consumption and the risk of prostate cancer ; however this is important as  it helps to narrow down factors that might be involved in causing and preventing prostate cancer.
There have been a number of studies looking at the role of diet and dietary supplements in helping to prevent or lower the risk of getting prostate cancer. For example, the SELECT trial looked at the effect of selenium and vitamin E. This trial showed that there was no evidence that selenium or vitamin E supplements have any benefit in prostate cancer prevention. In fact, the SELECT trial found that Vitamin E taken alone increased the risk of prostate cancer.
Likewise soy, green tea, lycopene (found in tomatoes) and fish consumption have all been studied but have failed to show clear enough results. Some trials have shown benefits in the past but when the trials were repeated the benefits have not been repeated.  It may be that some of these dietary supplements may have a beneficial effect in certain populations but more trials will need to be done to find this out. At this time there is not enough evidence to recommend any nutritional supplements or special diet for the prevention of prostate cancer.
Recently, (July 2013) there was a study that raised the possibility that high intakes of omega 3 fatty acids - for example, taken through the use of fish oil supplements - could increase the risk of developing a high-grade prostate cancer. However the study did not account for other risk factors for prostate cancer, which would be necessary before it could be considered definitive. We do know that eating fish is heart-healthy and prostate-healthy; we do not know if taking fish oil supplements has an impact on prostate cancer risk either way.
Talk to your doctor if you need further advice about taking fish oil supplements. Your doctor can take your general health into account and factor in the other known health benefits of taking omega 3 fish oil supplements before helping you to decide whether to take fish oil supplements or not.
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Date Last Reviewed: 
Monday, July 7, 2014
Date Last Revised: 
Thursday, February 12, 2015