Taking the fizz out of the association between carbonated drinks and oesophageal adenocarcinoma

There is an association between the intake of carbonated soft drinks and subsequent development of oesophageal adenocarcinoma in the US. There is biological plausibility to the hypothesis that carbonated drinks may cause oesophageal adenocarcinoma but, as these data are ecological, any association may be due to the ecological fallacy. Lagergren et al address this in a case-control study that has been reported previously (

) . All 189 patients with oesophageal adenocarcinoma and 262 patients with cardia cancer were compared with 820 population controls. The majority of participants were interviewed face-to-face about soft drinks consumed 20 years ago. Very high consumption of carbonated drinks (more than 10 times a week) was not associated with risk of oesophageal adenocarcinoma (odds ratio (OR)  =  1.15; 95% CI  =  0.67 to 2.00) or cardia adenocarcinoma (OR  =  1.10; 95% CI  =  0.7 to 1.72). It is not …