Fatalities on the liquid-protein diet: an analysis of possible causes

Reports of deaths occurring in patients using variants of the liquid-protein diet (LPD) have raised some questions about the safety of this procedure for the management of obesity. Case reports involving 44 publicized deaths were reviewed. Possible causes of death including such factors as potassium and/or electrolyte deficiencies, inadequate or poor quality protein, imperfect patient selection or compliance, an associated medications or disease were examined. Data in eight patients are insufficient for analysis or show that the patients were not using a LPD. Of the remaining 36 patients 32 were inappropriately managed as judged by conservative standards. Four patients who may have been properly managed all had known preexisting cardiac disease. The analysis does not identify any single factor which is responsible for the deaths. It shows that the procedure was widely misused and suggests that this contributed in multiple ways to the fatalities. No properly managed patient died as a direct result of the LPD and the cardiac deaths could not be ascribed to the LPD. Since the LPD, when properly supervised, has demonstrated great promise in the management of obesity, it is suggested that caution be exercised in dismissing the LPD because of adverse publicity.