Paul McGlothin Posted September 1, 2012 Report Share Posted September 1, 2012 In response to recent reports and articles referring to the calorie restriction lifestyle and the latest findings suggesting the discredit of the life extending qualities of the practice, The CR Society and the CR Way wish clarify the findings. Nature.com published following paper: Impact of caloric restriction on health and survival in rhesus monkeys from the NIA study Julie A. Mattison, George S. Roth, T. Mark Beasley, Edward M. Tilmont, April Handy, Richard L. Herbert, Dan L. Longo, David B. Allison, Jennifer E. Young, Mark Bryant, Dennis Barnard, Walter F. Ward, Wenbo Qi, Donald K.Ingram & Rafael de Cabo Nature(2012)doi:10.1038/nature11432 Published online 29 August 2012 PMID: 22932268, NIH, NLM, PubMed access to Medline biomedical citations Calorie restriction (CR), a reduction of 10–40% in intake of a nutritious diet, is often reported as the most robust non-genetic mechanism to extend lifespan and healthspan. CR is frequently used as a tool to understand mechanisms behind ageing and age-associated diseases. In addition to and independently of increasing lifespan, CR has been reported to delay or prevent the occurrence of many chronic diseases in a variety of animals. Beneficial effects of CR on outcomes such as immune function1, 2, motor coordination3 and resistance to sarcopenia4 in rhesus monkeys have recently been reported. We report here that a CR regimen implemented in young and older age rhesus monkeys at the National Institute on Aging (NIA) has not improved survival outcomes. Our findings contrast with an ongoing study at the Wisconsin National Primate Research Center (WNPRC), which reported improved survival associated with 30% CR initiated in adult rhesus monkeys (7–14years)5 and a preliminary report with a small number of CR monkeys6. Over the years, both NIA and WNPRC have extensively documented beneficial health effects of CR in these two apparently parallel studies. The implications of the WNPRC findings were important as they extended CR findings beyond the laboratory rodent and to a long-lived primate. Our study suggests a separation between health effects, morbidity and mortality, and similar to what has been shown in rodents7, 8, 9, study design, husbandry and diet composition may strongly affect the life-prolonging effect of CR in a long-lived nonhuman primate. The results state that rhesus monkeys fed a calorie-restricted diet didn't live any longer than monkeys on a higher-calorie diet. Regardless of the diet, the longest lifespan seems to hover around 40 years of age. Half the monkeys that began the study while young were still alive, but the researchers say, based on survival patterns, they forecast the lingering calorie-restrictors and controls will all live to be similar in age. The CR Society and the CR Way, which advocate and practice calorie restricted lifestyle: respond to the latest study: we remind members that these monkeys are caged animals, housed in small wire spaces for their entire lives. Incarceration is torture. Human prisoners are well known to have shortened lifespans. So finding that caged living conditions do not produce the same results as the great body of research does that shows that calorie restriction extends life in all species, studied – including humans. We asked Dr. Joseph Dhahbi, to comment: "Housing of intelligent mammals in small cages is cruel. This affects the outcome more than diet." Dr. Luigi Fontana voiced similar views: “If you’re in a single cage for your whole life, and are a highly intelligent animal like a primate, deprived of contact with other peers, and on top of that you’re calorically restricted — can you imagine the psychological depression issues that will ensue?” From the stockpile of evidence in support of calorie restriction for lifespan extension we share one example: the Okinawan elders. A 2007 study of elderly Okinawans who limited calories for 60 years by only 11% showed their life expectancy at age 65 to be the highest in Japan, possibly the world. Females had life expectancies that averaged 89.1 years and males, 83.5 years. A decade of research, much of it involving CR Society members, at the School of Medicine at Washington University in St. Louis further confirms that human calorie restrictors show similar benefits to calorie-restricted animals. Consider their 2009 paper: Fontana L: Modulating human aging and age-associated diseases. “… calorie restriction without malnutrition and moderate protein restriction with adequate nutrition may have additional beneficial effects on several metabolic and hormonal factors that are implicated in the biology of aging itself.” These two examples are but a fraction of all the confirmatory data published in support of a calorie restricted lifestyle in extending lifespans. Caution should be used when considering recent reports suggesting results to the contrary. Here is more: http://calorierestri...ngevity-effect/ http://arc.crsociety...1800#msg-211800 http://arc.crsociety...81,211885#REPLY Paul Link to comment Share on other sites More sharing options...
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