Diet and prostate cancer risk
Bottom line
Higher intake of selenium, pulses, and tomatoes or lycopene seem to be protective, and very high calcium intake above 2000 mg/day seems to increase risk.
Background
For many forms of cancer, diet and lifestyle can affect risk. Generally, diets higher in fruit and vegetables seem to be protective against cancer, though this is not known for certain for prostate cancer.
Reference
PC Dagnelie et al. Diet, anthropomorphic measures and prostate cancer risk: a review of prospective cohort and intervention studies. BJU International 2004 93: 1139-1150.
Systematic review
The systematic review sought prospective studies examining diet or anthropomorphic variables against risk of prostate cancer incidence or mortality. Intervention studies or cohort studies were used if dietary intake was measured by blood biomarkers, questionnaires, or interviews.
Results
There were four randomised placebo controlled studies and 37 cohort studies. Most of the trials were small, with 4 in 10 having fewer than 100 cases of prostate cancer. A similar proportion used mortality, or a combination of incidence and mortality as an end point.
Consistent effects between studies were found for the following:
- Selenium: in five of six cohort studies there was a protective effect of selenium, and in one randomised trial.
- Pulses: three cohort studies showed a protective effect.
- Tomatoes/lycopene: three out of four cohort studies showed a protective effect.
- Calcium: two cohort studies showed no effect, but two other studies had an increased risk when intake was above 2000 mg a day.
No other consistent effects were seen for meat and fish consumption, vegetables, fruit, vitamin A and carotenoids, vitamin E, fat, coffee and tea, alcohol, or anthropomorphic variables.
Comment
This is the best evidence so far concerning lifestyle and prostate cancer risk in men.