Diet and bladder cancer: a meta-analysis of six dietary variables.
In 1996, more than 300,000 new cases of bladder cancer were diagnosed worldwide. Besides tobacco smoking, occupation, and other factors, diet may play a role in causation of this illness. The authors performed a meta-analytical review of epidemiologic studies linking six dietary factors to bladder cancer. These factors include retinol, beta-carotene, fruits, vegetables, meat, and fat. Increased risks of bladder cancer were associated with diets low in fruit intake (relative risk (RR) = 1.40, 95% confidence interval (CI): 1.08, 1.83), and slightly increased risks were associated with diets low in vegetable intake (RR = 1.16, 95% CI: 1.01, 1.34). Elevated risks were identified for diets high in fat intake (RR = 1.37, 95% CI: 1.16, 1.62) but not for diets high in meat intake (RR = 1.08, 95% CI: 0.82, 1.42). No increased risks were found for diets low in retinol (RR = 1.01, 95% CI: 0.83, 1.23) or beta-carotene (RR = 1.10, 95% CI: 0.93, 1.30) intake. These results suggest that a diet high in fruits and vegetables and low in fat intake may help prevent bladder cancer, but the individual dietary constituents that reduce the risks remain unknown.
Steinmaus
C M
CM
Division of Occupational and Environmental Medicine, University of California at San Francisco, USA.
Nuñez
S
S
Smith
A H
AH
D004041:Dietary Fats / Q000009:adverse effects*; D005260:Female; D005638:Fruit; D006801:Humans; D008297:Male; D008460:Meat; D012306:Risk; D001749:Urinary Bladder Neoplasms / Q000209:etiology* / Q000517:prevention & control*; D014675:Vegetables; D014801:Vitamin A / Q000008:administration & dosage*; D019207:beta Carotene / Q000008:administration & dosage*
D004041:Dietary Fats; D019207:beta Carotene; D014801:Vitamin A