This third edition is completely updated with the latest scientific information on calorie restriction (CR), and with an all-new introduction, by the coauthors of The Longevity Diet, CR Society president Brian Delaney and Lisa Walford. The still-authoritative book on aging and life extension: Beyond the 120 Year Diet, decades ahead of its time when it was originally published in a previous edition in 1986, definitively presents the science behind CR, the low-calorie and nutrient-rich diet, and clearly describes how CR substantially reduces the risk of virtually all diseases that accompany aging, including heart disease, cancer, diabetes, autoimmune disease, osteoporosis, and neurodegenerative diseases such as Alzheimer's and Parkinson's.