IGF 1 LR3 The Muscle Building Peptide Everyone's Talking About IGF 1 LR3 is one of the most powerful performance peptides used for muscle growth, recovery, and fat loss. It's a modified version Gut derived IL 13 contributes to growth via promoting hepatic IGF 1 production Microbiome Springer Nature Link IGF 1: Miracle Hormone or Health Hazard? Diet vs Disease IGF 1: Miracle Hormone or Health Hazard? Diet vs Disease Insulin like growth factor 1 promotes cell cycle progression via upregulation of cyclin D1 expression through the phosphatidylinositol 3 kinase nuclear factor B signaling pathway in FRTL thyroid cells Acta Pharmacologica Sinica