IGF1 and nutritional deficiency disease: Since several physiologic variables cause major changes in IGF-I, this suggests that states of low IGF-I and high IGFBP-2 (such as malnutrition or advanced age) would have a low aBMD;33–35 whereas high IGF-I and high IGFBP-2 would be anabolic.36–38 Therefore, optimal use of this peptide may require selection of clinical conditions wherein there is maintenance of normal IGF secretion or pharmacologic manipulation to increase IGF production.