An increased body mass index may be protective in surgical intensive care unit patients. Hutagalung et al. [17, 18] analysed ICU and hospital mortality in 9,935 patients, and found that both overweight (BMI 25-29.9 kg/m 2 ) and obese (BMI 30-39.9 kg/m 2 ) patients showed a significantly lower 60-day hospital mortality than very obese and even normal weight patients. Interestingly, the improved survival prevailed despite a higher incidence of AKI in these specific weight groups, as already shown in another recent study [18] .