A new study conducted in an Italian population suggests that higher adherence to Mediterranean diet could be associated with an almost 35% lower risk for bladder cancer. The findings were published in the journal Nutrients.
Researchers conducted a case-control study using 690 bladder cancer cases and 665 control individuals to evaluate the association between Mediterranean diet and bladder cancer risk. Adherence to the Mediterranean diet was assessed using a Mediterranean Diet Score (MDS), with scores 0 and 9 indicating minimal and maximal adherence, respectively.
Compared to the MDS of 0-3, the OR for bladder cancer corresponding to the MDS of 4-5 was 0.72 (95% CI, 0.54-0.98) and OR corresponding to the MDS of 6-9 was 0.66 (95% CI, 0.47-0.93). If all patients showed a high adherence to Mediterranean diet (i.e., MDS of 6-9), an estimated 12.6% of bladder cancer cases would have been avoided. The risk for bladder cancer did not reveal substantial heterogeneity across strata of sex, age and education. When individual components of the MDS were considered, inverse associations were observed for greater consumption of legumes (OR, 0.52; 95% CI, 0.40-0.69), vegetables (OR, 0.70; 95% CI, 0.53-0.92) and fish (OR, 0.68; 95% CI, 0.53-0.87).
According to the authors, Mediterranean diet has been linked to lower levels of inflammatory markers including C-reactive protein, IL-6, and adiponectin and to a reduction in oxidative cells stress. Although adjustments were made for some confounders including BMI, the authors warn that residual confounding effect of tobacco smoking and other lifestyle factors cannot be completely ruled out.
