A large prospective Swedish study reported by Susanna C. Larsson, PhD, of the Unit of Nutritional Epidemiology at the Institute of Environmental Medicine at Karolinska Institutet in Stockholm, Sweden, and colleagues found a 2.2-fold increased risk of gallbladder cancer in people who consumed two or more servings of sweetened beverages a day compared with nonconsumers. The researchers also found a 1.8-fold increase in extrahepatic biliary tract cancer in consumers of sweetened beverages compared with nonconsumers. Sweetened beverages often contain high amounts of sucrose, which was also positively associated with the risk of gallbladder cancer in this study, which was published in the Journal of the National Cancer Institute.
Researchers analyzed data gathered from 70,832 Swedish adults (31,258 women, aged 49–83, and 39,574 men, aged 45–79) enrolled in the Swedish Mammography Cohort and the Cohort of Swedish Men. The participants were free of cancer and diabetes and completed a food frequency questionnaire at baseline. Participants were asked about their education, smoking habits, weight, height, physical activity, alcohol consumption, and diet.
The incidence of biliary tract cancer was ascertained by record linkage with the Swedish Cancer Register. A Cox proportional hazards regression model was used to analyze the data. All statistical tests were two-sided.
During a mean follow-up of 13.4 years, the researchers found 127 cases of extrahepatic biliary tract cancer, including 71 cases of gallbladder cancer and 21 cases of intrahepatic biliary tract cancer. After adjustments were made for other risk factors, women and men in the highest category of combined sugar-sweetened and artificially sweetened beverage consumption had a statistically significantly increased risk of extrahepatic biliary tract cancer and gallbladder cancer.
The multivariable hazard ratios for two or more servings per day (200 mL/serving) of sweetened beverages compared with no consumption were 1.79 (95% confidence interval [CI] = 1.02–3.13) for extrahepatic biliary tract cancer and 2.24 (95% CI = 1.02–4.89) for gallbladder cancer. The corresponding hazard ratio for intrahepatic biliary tract cancer was 1.69 (95% CI = 0.41–7.03).
The findings support the hypothesis that high consumption of sweetened beverages may increase the risk of biliary tract cancer, especially gallbladder cancer, concluded the researchers. ■