The impact of the pleiotropic growth factor IGF-I on lung pathology has been controversial, where elevated IGF-1 levels were reported in the broncho-alveolar lavage fluid of early ARDS patients [34], whereas low circulating levels were recently proposed as a potential predictor of SARS-CoV-2 infection severity and mortality [14, 35–37]. Here, IGF1 is linked to acute respiratory distress syndrome.