Calorie Restriction and Aging
Calorie Restriction and Aging - What They Didn't Tell You On OprahBy Tom Venutowww.BurnTheFat.com
On an episode of Oprah, one of the guests - a 51 year old man with the heart of a 20 year old said that he had been following a calorie restriction plan.
Experts have noted that he may be one of the first people to reach 120 years old by following this special nutrition plan.
There have been stories both in lay press and scientific press about calorie restriction and aging for many years and it's been a frequent talk show topic on 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's show.
I’ve seen a many strange things in the field of health, and although calorie restriction and aging (CR) is the subject of serious scientific study, I consider CR to be a strange thing. Of course, that’s because I choose a different lifestyle - the lean muscle-friendly "Burn The fat, Feed The Muscle" lifestyle. But, there’s more than one good reason why I’m not a an advocate of CR.
Allow me to elaborate on this:
Hunger while on a diet is always a challenge. There’s some feeling of hunger even with conservative calorie deficits of 15-20% under maintenance level.
Extended periods of feeling hunger is one of the biggest reasons people fall off the weight loss wagon because it’s difficult to resist. This is why pharmaceutical and supplement companies spend millions of dollars on researching, developing and marketing appetite suppressants on which they make a handsome profit. Yet calorie restriction advocates put themselves through 30-50% calorie restrictions on a daily basis in hopes of extending their life span.
Practitioners of CR follow a low-calorie lifestyle, but they are not in a chronic 30% calorie deficit. What happens is their metabolisms slow down (that’s part of the idea behind CR - if you slow down your metabolism you also allegedly slow down the aging process).
Therefore, 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 a day if following the principles of CR. This is not just due to the "starvation mode" phenomenon, that’s only one part of it. It’s mainly because he loses weight until he is very thin and his smaller body doesn’t need as many calories as it needed before.
Calorie Restriction and Aging - Does Caloric Restriction Really Extend Lifespan?
The biological mechanism of lifespan extension through calorie restriction is not fully understood, but researchers state that it may involve alterations in energy metabolism, reduced oxidative damage, improvements in insulin sensitivity, modulation of protein metabolism, reduction of glycation, down-regulation of pro-inflammatory genes and functional changes in both neuroendocrine and autonomic nervous systems.Calorie Restriction and Aging
Mouse studies on CR go back as far as 1935 and studies conducted on monkeys began in the late 80’s. So far the results are clear on one thing one: calorie restriction does in fact increase lifespan in rodents and other lower species (worms and flies). Studies suggest that the life of laboratory rats is 25% longer with CR. Primate studies are still underway and humans have been experimenting with CR for quite some time. In primates and humans, biomarkers of aging show signs of slower aging with Calorie Restriction. This makes many proponents talk about CR like it's a sure-thing. Like it's already proven through double-blind randomized clinical human trials.
The truth is, there is NO direct scientific experimental evidence that proves you will live longer from practicing CR. Due to the length of human lifespans, we won't have the necessary data for at least another generation or even multiple generations. Even then, it'll still be speculative if CR will extend human life at all and if so, by how much. I’ve seen guesses in scientific literature ranging from 3 to 13 years, provided that CR is practiced during an adult's entire lifetime.
Jay Phelan, a renowned biologist at UCLA is skeptical though. He says the potential for life extension is on the lower end of that range. Furthermore, he also states that the increase is so small that it’s not worth being semi-starved.Calorie Restriction and Aging
"There is no current evidence that lifelong calorie restriction leads to an increased lifespan in primates. It’s certainly tantalizing that things like blood pressure or heart rate look healthier and I believe they are. Whether or not this translates to an increased lifespan, I don’t know. I predict that it doesn’t."
I don’t quibble qualitatively with their research results. Sure, it will increase lifespan, but it will not increase it by 50% or 60%, nor by 20% or 10% - it might increase it by only 2%. Thus, 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 will say no thanks".
Calorie Restriction and Aging - Is prolonged caloric restriction unhealthy?
If calorie restriction is practiced with optimal nutrition (CRON), it is not in itself unhealthy. Actually, it appears that the reverse is true. First, the weight loss that comes with low calories produces improvements in the health markers, as one would expect. Second, the selective choice of foods from CRON practitioners, where they pick high nutrient foods and avoid empty calories means that they are making very healthy food choices. Third, advocates say that the CR improves health. Calorie Restriction and Aging
By losing fat and maintaining ideal body composition (the body fat to lean muscle ratio) and eating high nutrient density foods, I think that even at a normal caloric intake, you will get significant health and longevity benefits. I also propose that gaining muscle in a natural way (without using steroids) will increase your quality of life today and as in old age.
We are not lab rats so none of us knows when our day will come. We could get plucked off this physical plane of existence at any moment and we have no control over how it happens. My belief is that we should make lifestyle decisions based on quality of life, not just quantity. That includes our quality of life today as well as our future quality of life. Maybe we need to be focusing more on our "health span" rather than life span.Calorie Restriction and Aging
Calorie Restriction and Aging - Downsides of Calorie Restriction
One fact about calorie restriction that often doesn't get mentioned on talk shows is that the benefits of CR decline if you start CR at a later age. This was discussed in a research paper from the Journal of Nutrition called Starving for life: what animal studies can and can't tell us about the use of caloric restriction to prolong human lifespan.
The author, John Speakman from the School of Biological Sciences at the University of Aberdeen in Scotland, said that the later in life you begin to practice CR, the less of an increase in lifespan you can expect to achieve. Even if CR proponents are right, if you start in your late 40’s or mid 50’s, the benefit would be minimal. If you start in your 60’s the effect would be almost non-existent. Essentially, you have to "starve for life" to get benefits.Calorie Restriction and Aging
While some CR practitioners claim that they don't feel hunger and cite studies suggesting that hunger decreases during starvation, Speakman and other researchers say that hunger remains a big problem during CR - especially in today’s modern society where we are surrounded with all sorts of convenience food and numerous eating opportunities.
"Neuroendocrine profiles support the idea that animals under CR are continuously hungry. The feasibility of restricting calorie intake in humans for many decades is questionable".Calorie Restriction and Aging
Let’s imagine for a moment that CR is totally legit and that all claims are true. Many of the proposed benefits of CR come at the expense of what many of us are trying to do here: gain and maintain lean body muscle mass. One spokesman for CR is 6 feet tall and 130 pounds and another poster boy for CR is 6 foot tall and 115 lbs. Measurements of rodents under CR not only show large reductions in muscle but also bone mass.
I'm not suggesting that CR practitioners are anorexic, however, they are losing large amounts of fat-free tissue and that is obvious for all to see when you look at their bony physiques. I am not imposing my body standards on others, but 115 to 130 lbs at 6 foot tall is underweight for a man by any standard I think. Furthermore, researchers say that at the body mass indices sustained by most voluntary CR practitioners, the females would become amenorrheic. "One thing that is completely incompatible with a CR lifestyle is reproduction" says Speakman.Calorie Restriction and Aging
With that kind of atrophy, one must wonder what their quality of life will be like at old age. While many people struggle with body fat for most of their lives, I’m sure almost everyone knows an elderly person who has the opposite problem: they are seriously underweight and struggle to eat enough to maintain lean body mass.
My grandmother was under 80 lbs before she passed away. We couldn't get her to eat. She was very weak and frail. I have reported many times about research showing how most overweight people underestimate calorie intakes and eat more than they think. In elder care homes, the research has often showed the opposite - the patients overestimate how much they eat. They swear they are eating enough, but they aren't and they keep losing weight. With underweight, atrophied seniors, weakness means less functionality and lower quality of life and a fall can mean more than broken bones, it can be life-threatening.Calorie Restriction and Aging
Calorie Restriction and Aging - Life Extension With More Muscle
While there is some commonality between CRON and the way I recommend eating (high nutrient density, low calorie density foods), in most regards, CR is the opposite of my how my approach is structured.
In my Burn The Fat, Feed The Muscle system, we go for a higher energy flux nutrition program, which means that because we are weight training and doing cardio and leading a very active lifestyle, we get to eat more. Because we are active and well-trained, eating more doesn't have a negative effect as it would in the case of a sedentary person, who might get sick and fat from the additional calories.
Us active folks take those calories, burn them for energy, partition them into lean muscle tissue and we enjoy a faster metabolism and extremely high quality of life. Calorie Restriction and Aging
As a bodybuilder, CR is not compatible with my priorities, but if I were to practice a lower calorie lifestyle, I wouldn’t follow an aggressive CR approach for sure. I’d probably do as people in Okinawa. They have a very simple eatingphilosophy: hari hachi bu: eat until you are only 80% full.
While this doesn't mean there's a carefully measured 20% calorie deficit, it’s consistent with what we practice in the Burn The Fat, Feed The Muscle program for a fat loss phase. Incidentally, the Okinawans eat about about 40% less than Americans and they live 4 years longer than Americans.
If someone is being "sold" on CR by an enthusiastic CR spokesperson, or simply curious after watching the latest TV talk show (where they are looking for controversial stories), it’s important to know that there's more than one side to the any given story. Calorie Restriction and Aging
If you carefully read the entire body of research on CR, you will see that the experts are split right down the middle in their opinions about CR. CR for humans remains highly controversial and there are no guarantees that it will extend lifespan or stave off the effects of aging.Calorie Restriction and Aging
Researchers at the National Institutes of Health in Baltimore, MD put it this way:
"Because it's unlikely that an experimental study will ever be designed to address this question in humans, we respond by stating that “we think we will never know for sure.” We suggest that debate on this question be an academic exercise".
For more information about Burn The Fat, Feed The Muscle, the “longevity lifestyle with more muscle” visit: www.BurnTheFat.comCalorie Restriction and Aging
About the Author
Tom Venuto is a fat loss expert, steroid-free lifetime natural 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).
His program 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
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