Abstract
Sustaining health and extending longevity have been perpetual goals of all human societies. For almost as long, there has been an ongoing effort to develop treatments that could prevent aging and, more importantly, make us live longer and more healthily. At present, there is one known intervention that delays aging, increases lifespan and prevents diseases in many animal species: calorie restriction. There are other physiological factors that are believed to have corresponding impacts on longevity and aging, including growth hormone and the insulin/insulin-like growth factor 1 signaling pathway. However, there is still much debate regarding the complex action of growth hormone on lifespan and aging.
Acknowledgments
Supported by NIA, AG 19899 and U19 AG023122, Ellison Medical Foundation (MD, USA), SIU Geriatrics Medicine and Research Initiative (IL, USA), and Central Research Committee of Southern Illinois University School of Medicine (IL, USA). We would also like to thank Steven Sandstrom for his help with editing of this manuscript.