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 Oral delivery of novel human IGF 1 bioencapsulated in lettuce cells promotes musculoskeletal cell proliferation, differentiation and diabetic fracture healing ScienceDirect IGF 1 infusion to fetal sheep increases organ growth but not by stimulating nutrient transfer to the fetus American Journal of Physiology Endocrinology and Metabolism American Physiological Society Insulin like growth factor 1 deficiency and metabolic syndrome Journal of Translational Medicine Springer Nature Link