RESPONSE: Re: Carbonated Soft Drink Consumption and Risk of Esophageal Adenocarcinoma

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We appreciate the opportunity to address comments by Gallus et al. and by Mallath regarding our recent publication on carbonated soft drink (CSD) consumption and lack of increased esophageal adenocarcinoma risk. Gallus et al. analyzed data from a case–control study in Italy and reported a statistically non-significant inverse association between CSD consumption and risk of esophageal cancer. This was a study of esophageal squamous cell carcinoma rather than adenocarcinoma. Although these findings do not inform a possible link between CSDs and esophageal adenocarcinoma, the replication of our results for squamous cell carcinoma in a different population is reassuring.

Citing data from the Continuing Survey of Food Intakes by Individuals showing greater consumption of CSDs in younger and higher-income subjects, Mallath suggests that case–control differences in age and income might account for the lower consumption of CSDs by case patients than control subjects. We examined variables that could be associated with CSD consumption and, as shown in Table 1 of our manuscript, younger age and higher income were both related to higher CSD consumption among control subjects. Consequently, all of the risk estimates were adjusted for age, income, and education and several other potential confounders (shown in Table 2 of the manuscript). That the determinants of CSD consumption parallel those in the Continuing Survey of Food Intakes by Individuals suggests that the population control subjects in our study are representative of the general population.