Although the data indicates that CR can improve human health, these studies are still in their early phases and have yet to provide direct evidence demonstrating that CR indeed extends human life spans, as humans are already relatively long-living organisms. The analyses of human life spans would therefore need to rely on the observations of several generations before a solid conclusion can be drawn, something bound to be costly and difficult to maintain [6]. This is one reason why most human CR studies have been carried out for periods of only 6-12 months, or at most several years, at a time. In many cases, scientists have had no choice but to measure surrogate markers for longevity, which include fasting insulin levels, body temperature, and markers of oxidative stress [1]. Some are also concerned that due to differences in dietary habits, the increases in life spans via CR in other organisms may not be applicable to humans. We might have already reached our optimal level of energy intake, as unlike other animals, we do not eat ad libitum, and further limiting our diets may not yield such drastic changes. However, correlative evidence does exist supporting that people subjected to CR may live longer. For example, a study of the monks of Mount Athos in Greece between 1994 and 2007 found that their restricted diet—they only eat two small and ascetic, albeit nutritious, meals a day—contributes to their long lives and lower rates of cancer, heart disease, Parkinson’s disease, Alzheimer’s disease, and prostate cancer [8].
But cutting down on calories, despite its observed positive results, might not be a wholly enjoyable experience. Selecting foods that provide all the nutritional requirements but which are low in calories may sound easy, but refraining from consuming anything more than the bare minimum may prove to be more difficult: no sweet treats, no second helpings, and no dessert. Few people in today’s society would be able or willing to step up to this challenge. Nevertheless, the discovery of CR as a potential promoter of human longevity represents one significant step t o w a r d s achieving man’s desire f o r immortality. O t h e r p a r t i a l solutions to our age-old predicament e x i s t — a myriad of drugs, operations, or complicated diet regimens—but currently CR seems to be the most natural and promising method to extend lifespan and enhance health. Although we may never unlock the secret to living forever, modern science combined with something as simple as a well-controlled diet may allow us to enjoy longer, healthier lives.
Graphic by Amy Ng Works Cited 1. Trepanowski, J. F., Canale, R. E., Marshall, K. E., Kabir, M. M. & Bloomer, R. J. Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings. Nutr. J. 10, <http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3200169/?tool=pubmed> (2011). 2. Mattson, M. P. Energy intake, meal frequency, and health: a neurobiological perspective. Annu. Rev. Nutr. 25, <http://www.annualreviews.org/doi/full/10.1146/ annurev.nutr.25.050304.092526> (2005). 3. Coleman, R. J., et al. Caloric restriction delays disease onset and mortality in rhesus monkeys.” Science. 325, <http://www.sciencemag.org/content/297/5582/811. full.pdf?sid=c3e8babf-cf10-4444-aa76-dbe925ba3d6f> (2009). 4. Berrougui, H. & Khalil, A. Age-associated decrease of high-density lipoprotein-mediated reverse cholesterol transport activity. Rejuvenation Res. 12, <http:// www.ncbi.nlm.nih.gov/pubmed/19405812> (2009). 5. Lane, M. A., Ingram, D. K. & Roth, G. S. The Serious Search for an Anti-Aging Pill. <http://www.scientificamerican.com/article.cfm?id=the-serious-search-foran-2002-08> (2002). 6. Gertner, J. “The Calorie-Restriction Experiment”. <http://www.nytimes.com/2009/10/11/magazine/11Calories-t.html?pagewanted=all> (2009). 7. Zamora, A. “Calorie Restriction with Optimum Nutrition (CRON) - The Longevity Diet”. <http://www.scientificpsychic.com/health/crondiet.html> (2010). 8. Katz, N. “How Do Mount Athos Monks Stay so Healthy?”. <http://www.cbsnews.com/8301-504763_162-20056985-10391704.html> (2011).
Volume 4, Issue 2. 2012
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