Good, provocative epidemiology which, as always, raises more questions. A team looking for an explanation for the puzzling and dramatic rise in the incidence of esophageal cancer in the industrialized world suggests that it correlates with the equally alarming rise in the consumption of carbonated beverages, finding that in places like China and Japan where the one hasn’t happened, the other hasn’t either. As always, critics caution that ‘correlation is not causation’ (to use the mantra we are all taught when we learn to decipher research findings). — BBC