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Calorie Restriction for Life Extension: What They Didn’t Tell You on Oprah (Part 1)

26 April 2009 202 views Comments

Calorie Restriction for Life Extension: The Real Truth

On a recent episode of the Oprah show, one of the guests was a 51 year old man with the heart of a 20 year old. He’s been following a calorie restriction plan and they said he might be one of the first people to reach 120 years old by following this plan. There have been stories both in the lay press and scientific press about calorie restriction for years and it has been a frequent talk show topic on other many other TV shows. However, before you cut your calories in half in hopes of adding another decade onto your life, you’d better get the other half of the story they didn’t talk about on Oprah.

I’ve seen a lot of strange things in the health field, and although calorie restriction (CR) is the subject of serious and legitimate scientific study, I consider CR to be one of those strange things. Of course, that’s because I choose a different lifestyle – the muscle-friendly Burn The fat, Feed The Muscle lifestyle – but there’s more than one reason why I’m not a CR advocate:

Hunger while dieting is almost always a challenge. There’s some hunger even with conservative calorie deficits of 15-20% under maintenance. Prolonged hunger is one of the biggest reasons people fall off the weight loss diet wagon because it’s unpleasant and difficult to resist. This is why pharmaceutical and supplement companies spend millions of dollars on researching, developing and marketing appetite suppressants. Yet CR advocates put themselves through 30-50% calorie restriction on a daily basis as a way of life in the hopes of extending life span or health.

Practitioners of CR follow a low-calorie lifestyle, but technically, they are not in a chronic 30% calorie deficit. That would be impossible. What happens is their metabolisms get very slow (that’s part of the idea behind CR; if you slow down your metabolism, you allegedly slow down aging). So a 6 foot tall man who would normally require nearly 3,000 calories to maintain his weight, might eventually reach an energy balance at only 1800 or 1900 calories. This is not just due to a ‘starvation mode’ phenomenon, that’s only part of it. It’s primarily because he loses weight until he is very thin and his smaller body doesn’t need many calories any more.

Does caloric restriction really extend lifespan?

The biological mechanisms of lifespan extension through calorie restriction are not fully understood, but researchers say it may involve alterations in energy metabolism (as mentioned above), reduced oxidative damage, improvements in insulin sensitivity, reduction of glycation, modulation of protein metabolism, downregulation of pro-inflammatory genes and functional changes in both neuroendocrine and autonomic nervous systems.

Mouse studies on CR go back as far as 1935 and monkey studies began in the late 1980’s. So far the results are clear on one thing: caloric restriction does increase lifespan in rodents and other lower species (yeast, worms and flies). Studies suggest the life of the laboratory rat is 25% longer with CR (even longer with aggressive CR). Primate studies are still underway and humans have been experimenting with CR for some time. In primates and humans, biomarkers of aging show signs of slower aging with CR. This makes many proponents talk about this CR as if it were a sure-thing, already proven through double-blind randomized clinical human trials.

The truth is, there is NO direct experimental evidence that you will live longer from practicing CR. Due to the length of human lifespans, we will not have the necessary data for at least another generation and perhaps multiple generations. Even then, it will still be highly speculative whether CR will extend human life at all and if so how much. We can only estimate. I’ve seen guesses in the scientific literature ranging from 3 to 13 years, if CR is practiced for an entire adult lifetime.

Jay Phelan, a biologist at UCLA is skeptical. He says the potential life extension is on the lower end of that range and the increase is so small that it’s not worth the semi-starvation:

“There is no current evidence that lifelong caloric restriction leads to increased lifespan in primates. It’s certainly tantalizing that things like blood pressure or heart rate look as though they are a lot healthier and I believe they are. Whether or not this translates to a significantly increased lifespan, I don’t know. I predict that it doesn’t.”

I don’t quibble qualitatively with their results. Yes, it will increase lifespan, but it will not increase it by 50% or 60%, it won’t increase it by 20% or 10%, it might increase it by 2%. So if you tell me that I have to do something horrible for every day of my life for a 2% benefit – for an extra year of life – I say no thanks.”

Stay tuned for parts 2 and 3!

For more information about Burn The Fat, Feed The Muscle, the “longevity lifestyle with more muscle”, visit: www.BurnTheFat.com

Train hard and expect success,

Tom Venuto
Fat Loss Coach
www.BurnTheFat.com

About the Author:
Tom Venuto is a fat loss expert, lifetime natural (steroid-free) bodybuilder, independent nutrition researcher, freelance writer, and author of the #1 best selling diet e-book, Burn The Fat, Feed The Muscle: Fat-Burning Secrets of The World’s Best Bodybuilders & Fitness Models (e-book) which teaches you how to get lean without drugs or supplements using secrets of the world’s best bodybuilders and fitness models. Learn how to get rid of stubborn fat and increase your metabolism by visiting: www.burnthefat.com

References:

Hunger does not diminish over time in mice under protracted caloric restriction. Hambly C, Mercer JG, Speakman JR.Rejuvenation Res. 2007 Dec;10(4):533-42.Aberdeen Centre for Energy Regulation and Obesity (ACERO), Rowett Research Institute, Bucksburn, Aberdeen, Scotland, United Kingdom.

Starving for life: what animal studies can and cannot tell us about the use of caloric restriction to prolong human lifespan.Speakman JR, Hambly C. J Nutr. 2007 Apr;137(4):1078-86. School of Biological Sciences, University of Aberdeen, Aberdeen AB24 2TZ, Scotland, UK.

Can dietary restriction increase longevity in all species, particularly in human beings? Introduction to a debate among experts. Le Bourg E, Rattan SI. Biogerontology. 2006 Jun;7(3):123-5.

The potential for dietary restriction to increase longevity in humans: extrapolation from monkey studies. Ingram DK, Roth GS, Lane MA, Ottinger MA, Zou S, de Cabo R, Mattison JA.Biogerontology. 2006 Jun;7(3):143-8. Laboratory of Experimental Gerontology, Intramural Research Program, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, MD 21224, USA.

Caloric restriction in humans: potential pitfalls and health concerns. Dirks AJ, Leeuwenburgh C.Mech Ageing Dev. 2006 Jan;127(1):1-7. Epub 2005 Oct 13, Wingate University, School of Pharmacy, 316 N. Main Street, Wingate, NC 28174, USA.

Caloric restriction and human longevity: what can we learn from the Okinawans? D. Craig Willcox, Bradley J. Willcox Hidemi Todoriki. Biogerontology (2006) 7: 173-177

Endocrine alterations in response to calorie restriction in humans. Mol Cell Endocrinol. 2009 Feb 5;299(1):129-36. Epub 2008 Oct 21. Redman LM, Ravussin E. Pennington Biomedical Research Center, 6400 Perkins Road, Baton Rouge, LA 70808, United States.

Caloric restriction in the presence of attractive food cues: external cues, eating, and weight. Polivy J, Herman CP, Coelho JS.Physiol Behav. 2008 Aug 6;94(5):729-33. Epub 2008 Apr 13. University of Toronto, Canada.

Life Extension by Calorie Restriction in Humans. Everitt AV, Le Couteur DG.Ann N Y Acad Sci. 2007 Aug 23, Centre for Education and Research on Ageing, University of Sydney, Concord, New South Wales, Australia.