The Link Between Fruit, Vegetables and Health - Prostate Cancer

Reference 7 presents results of a study in which the participants were 628 men from the Seattle area, WA, who were newly diagnosed with prostate cancer. They were compared to control participants - 602 men recruited from the same population and matched to case participants by age. Food consumption questionnaires were used to assess their diet over the 3- to 5-year period before diagnosis or recruitment.

No correlation was found between fruit intake and the risk of prostate cancer. In comparison, participants who had 28 or more servings of vegetables per week had a risk reduction of 0.65 (0.45 to 0.94 Margin of Error) compared to participants who ate less than 14 servings per week. An even stronger risk reduction was found when the study considered only cruciferous vegetables - 0.59 for participants (0.39 to 0.90 Margin of Error) who consumed three or more servings per week of cruciferous vegetables, compared to participants who consumed less than one serving a week.

The authors of the study point out that there are possibly significant sources of bias. In particular, the reliance on people's ability to recall their diet when diagnosed with prostate cancer is questionable. Therefore, in itself, the study results should not be taken literally; rather, it should be noted that the results do fit in with an overall pattern that suggests significant benefits from vegetables.