Does intensive insulin therapy improve outcomes compared to conventional insulin therapy in critically ill medical ICU patients? The Leuven 2 trial, a single-center randomized controlled study, investigated this question among 1200 adult patients admitted to the medical ICU at the University Hospital in Leuven, Belgium. Patients were randomized to receive either intensive insulin therapy (targeting blood glucose 80–110 mg/dL) or conventional insulin therapy (targeting <220 mg/dL). The primary outcome was all-cause hospital mortality. Overall mortality was not significantly different between groups. However, among the 767 patients who remained in ICU for ≥3 days, hospital mortality was significantly lower with intensive therapy. Intensive therapy also led to earlier weaning from mechanical ventilation, shorter ICU and hospital stays, and a lower incidence of new-onset acute kidney injury. Hypoglycemia occurred more frequently with intensive treatment and was associated with higher ICU mortality. The study concluded that while intensive insulin therapy did not reduce overall mortality, it may benefit long-staying ICU patients—though these patients cannot be identified at admission.