Do Dieting Monkeys Live Healthier and Longer Lives?Continued from page 1
To make sure the study is as applicable to humans as possible, the Wisconsin scientists provide the monkeys with human-like health care: diabetic monkeys are given insulin; the animals get dental care; and female monkeys suffering endometriosis--a painful condition of the uterine lining common to humans--may undergo surgery. The only other study of caloric restriction in nonhuman primates, at the National Institute on Aging, is larger (120 monkeys) and two years longer-running than the Wisconsin study. However, it may not be as applicable to humans because those monkeys are not given extensive medical care, and were put on their restricted diets at a much younger age, some immediately after weaning, which stunts growth, according to Colman. The Wisconsin researchers use all human medical equipment on the monkeys, Colman says, including an MRI scanner for upcoming brain-imaging studies. Each monkey will have two scans over a five-year period to monitor changes. Because caloric restriction's effects on the body seem to be general, there's no reason it shouldn't be good for the brain if it's good for other organs, says Sterling Johnson, assistant professor of medicine at the University of Wisconsin. Normal aging is accompanied by a slight decrease in brain volume, he says. When the monkeys die, samples of their brain tissue will be saved for future studies of caloric restriction's effects on gene expression in that organ, Johnson says. As mice age, genes associated with inflammation and the death of brain cells, for example, become more active, while many of those associated with metabolism become less active. Studies of aging in calorie-restricted mice in Weindruch's lab have demonstrated that the diet prevents about 70 percent of such age-related changes. In 2001, when the rhesus monkeys were middle-aged, Weindruch published a study showing that, although differences in gene expression existed between those primates on caloric restriction and the control group, the diet did not seem to prevent age-related changes in gene expression. Weindruch expects to get different results when his group does another round of tests, however, now that the monkeys are truly old--and now that technology exists to test specifically for rhesus monkey genes. In the previous round of testing, Weindruch and colleagues had to use chips with human genes on them, since rhesus monkey chips became available only recently. Whatever the mechanisms turn out to be, "there's something that happens with that extra reduction of food intake that really affects the aging process," says Joseph Kemnitz, director of the Wisconsin primate research center. Ultimately, the researchers hope to take what they learn about this process to help people maintain a high quality of life throughout old age. |
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Caloric Restriction Slows Aging in Monkeys
07/09/2009
Massachusetts Institute of Technology
Comments
Alex
10/03/2006
Posts:1
Basically, I have to question such wide-ranging benefits of low-cal diets simply because there is no place in nature where this is seen. Animals try to eat about as much as they can. If it were dramatically better for them not to do so, then why has natural selection not given instincts to all of us to stop eating at an optimal point?
Certainly over-eating is damaging, because it is so rare in nature for much food to be available. But likewise, why have not the hungriest tribes of the world not shown to the rest of us longer, healthier lives, lesser disease (yeah, right) and greater productivity?
kitk
10/04/2006
Posts:65
Worse : it's better for the species, that you die when you are not useful for your offspring anymore (Since being alive and old makes you eat the food of other reproducer).
May-be this is why we just die : to leave the room for the offspring and allows their genes to evolve.
We are kind of slaves to our genes.
Sly
10/04/2006
Posts:11
aymeric
10/04/2006
Posts:19
captainhurt
10/12/2006
Posts:2
agnes
10/12/2006
Posts:1
In addition, all the studies increased the vitamin levels of the cal. restricted group to make it even with the non-restricted group. While the amounts were the same, the amount/body mass was 25-30% different. It seems to me that this is very confounding.
It seems our Medical Societies bias against the benefits of vitamin intake is blinding them to a possible applicable result.
We should all be in shape, but be taking significantly more vitamins.
guetenburg
04/30/2007
Posts:6
Caloric restriction is not a miracle cure, but if done correctly, it could easily add 10 years of lifespan to humans.
gabrielg01
10/04/2006
Posts:400
I am asking because some human studies made the mistake to put controls on a cholesterol-dripping burger diet so what the studies actually measured was toxicity of control, rather than benefit of CR over an optimal non-CR diet.
John Schloen...
10/04/2006
Posts:1
gabrielg01
10/04/2006
Posts:400
Katie Bourza...
10/04/2006
Posts:2
Our doctors repeat a tiresome litany; lose weight, get some exercise, drink less alcohol; give up smoking; eat right; and pay your medical bills. They say this emphatically yet with no real hope because they can't live by their own advice.
What we need is a way to lose weight that doesn't require willpower or relocating to Mumbai India.
Phineas
10/04/2006
Posts:85
most animals work like hell to get enough food just to live. we humans also do, or should, work enough to balance our food intake. so if these monkeys are living in cages, being fed foods far more energy intensive than natural foods, this tells us nothing.
kitk
10/04/2006
Posts:65
captainhurt
10/12/2006
Posts:2
I enjoyed this report. The work of Dr. Rick Weindruch is especially important to me since his writings originally inspired me to begin calorie restriction twelve years ago. Some, who are not informed about the many benefits of a calorie-restricted lifestyle, may think that only a stoical few could practice calorie restriction and those who do live dreary lives, hoping for an unrealistic extension of life. Indeed, it almost seems a requirement for scientists or writers to include a phrase like the following in this article “it’s unlikely that most people could be able to stick with it.”
Your readers should know that for many successful CR practitioners “restriction” is really liberation – liberation from the idea that the amount of food intake is proportional to one’s happiness. For many of us, liberation from high-calorie intake results in living our full potential right now, with hopes for a longer life. I can state unequivocally that the health and happiness benefits are life transforming. Anyone who experiences the increased energy, the heightened cognitive capabilities, and the phenomenal health benefits of the calorie-liberation lifestyle will never want to go back to the rapid-aging way of life followed by a majority of our Society.
True, some will always take things to extremes and equate their failures with the essence of calorie restriction. But fortunately, thousands of practitioners can set the record straight. Confirming our positive experience is the visionary work of Dr. Luigi Fontana and Dr. John Holloszy (http://tinyurl.com/yxj3x9) at Washington University in Saint Louis School of Medicine with their longitudinal study on the effects of CR in humans. My wife and I are members of the 23-person cohort of the Calorie Restriction Society (www.calorierestriction.org) who are being thoroughly evaluated and compared against other cohorts. Already two well-reported papers have resulted:
Long-term calorie restriction is highly effective in reducing the risk for atherosclerosis in humans.
Proceedings of the National Academy of Sciences of the U. S. A..
2004 Apr 7;101(17):6659-63. Fontana L, Meyer TE, Klein S, Holloszy JO.
PMID: 15096581
Long-term caloric restriction ameliorates the decline in diastolic function in humans.
Journal of the American College of Cardiology. 2006 Jan 17;47(2):398-402.
Meyer TE, Kovacs SJ, Ehsani AA, Klein S, Holloszy JO, Fontana L.
PMID: 16412867
But perhaps the best news for health-minded folks is that in round three of the research, Dr. Fontana will be joined by Dr. Stephen Spindler (http://tinyurl.com/y97v79) and Dr Shin Imai (http://dbbs.wustl.edu/dbbs/website.nsf/RIB/107B3F3826243E9B86256D4E005B2D3A), who will explore the genetic and signal transduction aspects of calorie restriction.
We hope the results will be a beacon for all who want to live as long and healthfully as possible. To learn more use this link http://www.calorierestriction.org/ResearchOnAging.
Wishing you and your readers long health and happiness,
Paul McGlothin
VP, Research
The Calorie Restriction Society
Research@CalorieRestriction.org
pmcglothin
10/23/2006
Posts:1
I'd say: watch for the outcomes, it’s going to exciting.
(1) Minireview: the role of oxidative stress in relation to caloric restriction and longevity. Endocrinology. 2005 Sep; 146(9):3713-7. Epub 2005 May 26
(2) Caloric restriction, metabolic rate, and entropy. J Gerontol A Biol Sci Med Sci. 2004 Sep; 59(9):B902-15
(3) Aging in mouse and human systems: a comparative study. Ann N Y Acad Sci. 2006 May; 1067:66-82
Ivan Boyadzhiev, M.D.
Convex
Ivan Boyadzh...
10/27/2006
Posts:1
Simply, the answer is no. There is nothing new to report. You should compare this artticle with the many that have preceded it. The University of Wisconsin has one of the most active public relations departments I've encountered.
Studies in humans are always going to provide better data about humans than will studies in other species. Given that humans are volunarily participating in caloric restriction, the data from animal models has very little utility.
The reason that these studies continue is also a simple one: money. Weidruch's FY 2003 federal grants:
P01AG011915-10 $1,416,472 Dietary Restriction And Aging In Rhesus Macaques
P20CA103697-01 $586,000 Aging And Cancer Program
R01AG018922-03 $372,081 Gene Expression Profiling, Oxidative Stress And Aging
T32AG000213-13 $385,144 Biology Of Aging And Age-Related Diseases Training Grant
One issue that is never addressed in these UW-spin pieces is the effects of the research on the animals. In the Weindruch studies, these monkeys are individually housed for their entire lives. Individual housing is a well-recognized cause of emotional stress in rhesus monkeys closely associated with stereotypic behaviours and self-mutilation.
Is the knowledge gained from a lifetime of chronic hunger and loneliness really outweighed by the data generated?
[An aside: Just recently, the University of Wisconsin announced that they had destroyed sixty boxes of video tapes of experiments on primates at the UW. The university reported that they were destroyed 63 days following a denial of a open records request for a single tape. The WI state statutes require that requested documents be kept on hand for 60 days following a denial.]
Rick
11/02/2006
Posts:1
Elroch
03/01/2007
Posts:33
In addition, all the studies increased the vitamin levels of the cal. restricted group to make it even with the non-restricted group. While the amounts were the same, the amount/body mass was 25-30% different. It seems to me that this is very confounding.
It seems our Medical Societies bias against the benefits of vitamin intake is blinding them to a possible applicable result.
We should all be in shape, but be taking significantly more vitamins.
guetenburg
04/30/2007
Posts:6