IGF 1 LR3 (Insulin like Growth Factor 1 Long R3) is often called the "Holy Grail" of muscle building peptides because of its potent anabolic effects. In a Med Spa context, it is typically sought out Late life targeting of the IGF 1 receptor improves healthspan and lifespan in female mice Nature Communications IGF 1 & LR3 (Build Blend) Peptide Therapies Elite Health HRT Attenuated glucose stimulated insulin secretion during an acute IGF 1 LR3 infusion into fetal sheep does not persist in isolated islets Journal of Developmental Origins of Health and Disease Cambridge Core human IGF 1 LR3 protein 1000 g Human E. coli ReliaTech GmbH LR3 IGF I (Receptor Grade), Human GenScript