Increased Inflammatory Potential of Diet is Associated with Increased Risk of Prostate Cancer in Iranian Men.

Purpose: Various aspects of diet, including specific foods and nutrients, have been implicated to play a role in modulating inflammation and in the etiology of prostate cancer. Studies examining this association have been conducted primarily in Western countries; but none in Middle Eastern Countries.

Method: We examined the association between the dietary inflammatory index (DII) and prostate cancer in an ageand BMI-matched case-control study among 40-78 year-old Iranian males. A total of 50 incident cases and 100 controls attending the same hospital as the cases during the same time period were recruited. The DII is a literature-derived population-based dietary index developed to determine the inflammatory potential of individuals' diets and was computed based on dietary intake assessed using a previously validated semi-quantitative food frequency questionnaire (FFQ) that was expanded to assess diet and cancer in the Iranian population. Logistic regression was used to estimate odds ratios, with DII score fit as continuous and as a dichotomous variable.

Results: Multivariable-adjusted analyses revealed that men with higher DII score (>0.23) to be at higher risk of prostate cancer [odds ratio (OR) = 3.96; 95% CI =1.29-12.16, p-value = 0.02)] compared to men with lower DII scores (≤0.23).

Conclusion: These data suggest a pro-inflammatory diet, as indicated by increasing DII score, may be a risk factor for prostate cancer in Iranian men..