No surprises here.
Proton pump inhibitors are not glorified antacids. They can have significant side-effects, and should therefore not be prescribed indiscriminately nor consumed indefinitely
Taken at face value, this large scale retrospective nested case-control study reviewing 14 years of weight-reduction surgery records suggests that biliopancreatic diversion surgery is significantly associated with increased fragility fractures.
If the association is indeed true, it has practice-changing implications, especially in the post-surgical medical care and nutrition. And it has at least 1 plausible causal explanation: malabsorption.
But as with most retrospective epidemiological data, the study is deeply flawed by data gaps which rendered important confounders uncontrolled for: Vitamin D and calcium intake, anti-osteoporosis treatments (if any), menopause status, and even BMI.
But all is not lost. This study should prompt better designed prospective studies to answer this important research question.