IGF 1, the Cross Road of the Nutritional, Inflammatory and Hormonal Pathways to Frailty 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 IGF 1 LR3 Injection Benefits And How It Works The HCG Institute A Medical Review of IGF 1 LR3 Dosage, Side Effects and Safety Aspects