79 replies to this topic

[resveratrol]

I have no doubt that this must be bogus, since it appeared in the New York Times.

However, in the unlikely event that it's accurate, it would seem to undermine the idea of caloric restriction in humans, as well as some of the recent research linking obesity to cancer.

About two years ago, a group of federal researchers reported that overweight people have a lower death rate than people who are normal weight, underweight or obese. Now, investigating further, they found out which diseases are more likely to lead to death in each weight group.

Linking, for the first time, causes of death to specific weights, they report that overweight people have a lower death rate because they are much less likely to die from a grab bag of diseases that includes Alzheimer’s and Parkinson’s, infections and lung disease. And that lower risk is not counteracted by increased risks of dying from any other disease, including cancer, diabetes or heart disease.

http://www.nytimes.c...int&oref=slogin

Thoughts?

(Edit: and there's no link to the actual study either ... God forbid the public be allowed to fact-check that which the Times hath published).

[Mind]

First thought, it flies in the face of most every other study regarding wieght and its affect on disease and longevity.

[Shepard]

Also here:

http://www.physorg.c...s113592452.html

Besides, when you look into adipose tissue metabolism, claiming an advantage in being moderately overweight doesn't make sense. At least, not to me.

[Matt]

As I said on this forum before, these studies are becoming stupid now. They are constantly going back and fourth in what is and whats not good. IMO trust the animal evidence and rhesus monkey studies that are far better controlled. You're right in that this seems to contradict everything we learned over the last 7 decades about calories, body weight and longevity.

Calorie Restriction which typically results in a low body weight protects against Alzheimer's disease, it protects against Parkinson's disease, it protects against heart disease, diabetes, stroke, cancer (especially started from young age). Infectious disease is something I'm still unsure about in calorie restriction, even with the anecdotal evidence of improved immunity among CRers.

Looking at the primate evidence for example, this was just avoidance from being overweight. Results are remarkable in my opinion. (not an anti aging study). The CR monkeys on average lived to humans equivalent of 96 human years (AVERAGE)...

FROM CRON-WEB.ORG



[posted on behalf of CRON4healthy future; 17 Mar 2003]

Johns Hopkins is chiming on this one.

The punchline is that there are 117 monkeys, and 8(!) were DR, and 109 ate
their brains out.

The AL monkeys had a 2.6 fold increased risk of death. Hyperinsulinemia
led to a 3.7 fold increase in death, with the risk of death decreasing 7%
per unit of insulin sensitivity. In other words, less insulin sensitivity
means less life.

DR monkeys lived 32 years on average, AL lived 25 years. Interestingly,
the longest lived monkey was a diabetic monkey who lived to 40 years old
despite being ab-libitum. I guess luck will play a factor in all of this
as well.

This may have been posted before, but I guess this time we have the PMID as
well.

J Gerontol A Biol Sci Med Sci 2003 Mar;58(3):B212-9

Mortality and Morbidity in Laboratory-maintained Rhesus Monkeys and Effects
of Long-term Dietary Restriction.

Bodkin NL, Alexander TM, Ortmeyer HK, Johnson E, Hansen BC.

Obesity and Diabetes Research Center, Department of Physiology, School of
Medicine, University of Maryland, Baltimore. Department of Biostatistics,
Johns Hopkins University, Baltimore, Maryland.

[biknut]

I think it's got to have a lot to do with exercise. It just seems like no matter what your weight, sitting behind a desk all day is probably unhealthy. Bodies probably need a little stress in the form of exercise.

On the other hand running through the jungle trying to stay ahead of the lions is good exercise. Being a little overweight probably allows you put out more energy for longer.

[Mind]

There are also degrees of being overweight. If you are just 1 pound over your ideal weight you will probably not suffer as much ill health as when you are 20 pounds overweight.

[Live Forever]

There are also degrees of being overweight. If you are just 1 pound over your ideal weight you will probably not suffer as much ill health as when you are 20 pounds overweight.

20 lbs overweight would probably fall into the "obese" category that they said slightly overweight people beat. (in the above article, anyway)

overweight people have a lower death rate than people who are normal weight, underweight or obese.

[Live Forever]

Besides not making sense in relation to everything we have heard from studies over the past few decades on the subject, it doesn't make sense evolutionarily (to me anyway). I can see how being slightly underweight (CR) would mean that you would live longer, because your body would be tricked into thinking it was in a famine period, and would want to increase lifespan so that you would be able to reproduce once the famine passed, but I can not think of why being slightly overweight would provide any life lengthening benefit.

[krillin]

Did they use the BMI at time of death, or before contracting the disease that killed them? Alzheimers can cause you to lose weight, for example.

[Shepard]

If anyone is interested:

http://www.imminst.o...T&f=178&t=18559

[Live Forever]

If anyone is interested:

http://www.imminst.o...T&f=178&t=18559

Hmm, even after reading the study I can't tell if they measured the BMI of the person at or near their death date. If this is the case, then the cancer or whatever could be causing the body weight to be lower. (and thus put more of them into the lower weight groups)

Also, something to keep in mind is that this is a correlation study, not a causation study. In every animal causation study (CR related) that has been done, lower than average body weight caused the body to age slower.

[PWAIN]

There are also degrees of being overweight. If you are just 1 pound over your ideal weight you will probably not suffer as much ill health as when you are 20 pounds overweight.

Mind, did you read the article? The point is that being overweight (NOT OBESE) infers an advantage to mortality:

"A body mass index of 25 to 30, the so-called overweight range, “may be optimal,” she said."

So being 1 pound overweight will only give you a small ADVANTAGE wrt mortality.

I am a bit dissapointed at the closed minds on this forum. Consider:

"...the group from the Centers for Disease Control and Prevention and the National Cancer Institute reports..."

"Their paper is published today in the Journal of the American Medical Association."

So we have a report here from reputable organisations and published in a reputable journal. Lets just call it junk science because we don't like their findings.

Reading through the article, they also seem to be quite thorough with things like:

"Researchers tried to rule out those who were thin, because they might have been already sick. They also ruled out smokers, and the results did not change."

Which answers many of the posts here that question whether the weights measured were after illness.

This study may or may not be correct but at lest read the article and try to be objective.

[Live Forever]

I am a bit dissapointed at the closed minds on this forum. Consider:

"...the group from the Centers for Disease Control and Prevention and the National Cancer Institute reports..."

"Their paper is published today in the Journal of the American Medical Association."

So we have a report here from reputable organisations and published in a reputable journal. Lets just call it junk science because we don't like their findings.

Reading through the article, they also seem to be quite thorough with things like:

"Researchers tried to rule out those who were thin, because they might have been already sick. They also ruled out smokers, and the results did not change."

Which answers many of the posts here that question whether the weights measured were after illness.

This study may or may not be correct but at lest read the article and try to be objective.

The point is that it is at odds with so many other reputable sources and studies over the last few decades. I think it is just surprising to see a study completely at odds with so many other studies that makes people just a tad weary of the results. That said, I don't think anyone has called into question the results or called it "junk science". (at least not here) The methods of the study might be debated, but that is a far cry from calling something "junk science". (that is usually reserved for people on the fringe of science; faith healers, creationists, crystal healing proponents, etc, etc.)

[Mind]

I am a bit dissapointed at the closed minds on this forum. Consider:

Dude, all I am saying is that it is odd, because so many other studies correlate good health with lower weight. There is a difference between trying to rationalize this oddity and saying it is junk.

[shuffleup]

Maybe BMI is just a bad measure of weight characterization. I'm not sure what I would look like at a BMI of 20 but at 5'7" and currently 185 lbs I'd need to lose 50 lbs. to find out. I carry more than avg muscle mass and after having lose 45 lbs in the last 18 months people are (seriously) wondering if I've gone anorexic because I look much thinner now. 50 more pounds to get to optimal BMI and people would be doing interventions.

I'm not saying my current weight is healthy - I'm working to lose more. Just not down to the 'ideal' BMI.

Edited by shuffleup, 08 November 2007 - 12:05 AM.

[Matt]

See the below studies... I posted this somewhere else, bu its relevant here

Body mass index and mortality among US male physicians.
Ann Epidemiol. 2004 Nov;14(10):731-9.
PURPOSE: To assess the relationship between body mass index and mortality in a population homogeneous in educational attainment and socioeconomic status. METHODS: We analyzed the association between body mass index (BMI) and both all-cause and cause-specific mortality among 85,078 men aged 40 to 84 years from the Physicians' Health Study enrollment cohort. RESULTS: During 5 years of follow-up, we documented 2856 deaths (including 1212 due to cardiovascular diseases and 891 due to cancer). In age-adjusted analyses, we observed a U-shaped relation between BMI and all-cause mortality; among men who never smoked a linear relation was observed with no increase in mortality among leaner men (P for trend, <0.001). Among never smokers, in multivariate analyses adjusted for age, alcohol intake, and physical activity, the relative risks of all-cause mortality increased in a stepwise fashion with increasing BMI. Excluding the first 2 years of follow-up further strengthened the association (multivariate relative risks, from BMI<20 to > or = 30 kg/m2, were 0.93, 1.00, 1.00, 1.16, 1.45, and 1.71 [P for trend, <0.001]). In all age strata (40-54, 55-69, and 70-84 years), never smokers with BMIs of 30 or greater had approximately a 70% increased risk of death compared with the referent group (BMI 22.5-24.9). Higher levels of BMI were also strongly related to increased risk of cardiovascular mortality, regardless of physical activity level (P for trend, <0.01). CONCLUSIONS: All-cause and cardiovascular mortality was directly related to BMI among middle-aged and elderly men. Advancing age did not attenuate the increased risk of death associated with obesity. Lean men (BMI<20) did not have excess mortality, regardless of age.PMID: 15519894 [PubMed - indexed for MEDLINE]

Body mass index and patterns of mortality among Seventh-day Adventist men. Int J Obes. 1991 Jun;15(6):397-406.
This study examines the relationship between body mass index (BMI) and 26-year mortality among 8828 nonsmoking, nondrinking Seventh-day Adventist men, including 439 who were very lean (BMI less than 20 kg/m2). The adjusted relative risk comparing the lowest BMI quintile (less than 22.3) to the highest (greater than 27.5 kg/m2) was 0.70 (95 percent CI 0.63-0.78) for all cause mortality, 0.60 (95 percent CI 0.43-0.85) for cerebrovascular mortality, and 0.80 (95 percent CI 0.61-1.04) for cancer mortality. Very lean men did not show increased mortality. To assess whether the protective effect associated with low BMI is modified by increasing age, the product term between BMI and attained age (age at the end of follow-up or at death) was included as a time-dependent covariate. For ischemic heart disease mortality, age-specific estimates of the relative risk for the lowest quintile relative to the highest ranged from 0.32 (95 percent CI, 0.19-0.52) at age 50 to 0.71 (95 percent CI, 0.56-0.89) at age 90. Interaction was also seen for the next lowest quintile (22.4-24.2). There was a significant trend of increasing mortality with increasing BMI for all endpoints studied. For cancer and cerebrovascular mortality the P-values for trend were 0.0001 and 0.001 respectively. For the other endpoints the P-values were less than 0.0001. Thus, there was no evidence for a J-shaped relationship between BMI and mortality in males. While the protective effect associated with the lowest BMI quintile decreased with increasing age for ischemic heart disease mortality, it remained greater than one at all ages. The relatively large number of subjects who were lean by choice, rather than as a result of preclinical disease or smoking, may explain these findings.PMID: 1885263 [PubMed - indexed for MEDLINE]


Relationship between morbidity and body mass index of mariners in the Japan Maritime Self-Defense Force fleet escort Force
To establish a practical weight management program for mariners in the Japan Maritime Self-Defense Force (JMSDF) Fleet Escort Force, the relationship between morbidity and body mass index (BMI) was studied. To estimate morbidity, 10 medical problems were used as indices (hyperlipidemia, hyperuricemia, diabetes mellitus, lung disease, heart disease, upper gastrointestinal tract disease, hypertension, renal disease, liver disease, and anemia). A curvilinear relationship was found between morbidity and BMI, in which a BMI of 17.5 was associated with the lowest morbidity. This curvilinear pattern was more complex than a curve reported previously for Japanese civilians. Using the present curve and aiming for a BMI of 17.5 will help in the design and implementation of a practical management program for health promotion in the JMSDF.
http://cat.inist.fr/...&cpsidt=1101215


NIHNC, CDC, & DHHS. (1985). Body weight, health and longevity: conclusions and recommendations of the workshop. Nutrition Reviews, February, 43(2), pages 61-3.
In 1985, the National Institute of Health, Centers for Disease Control, and the Department of Health and Human Services published a "special report" stating: "[S]tudies based on life insurance data, the American Cancer Society Study and other long-term studies, such as the Framingham Heart Study and the Manitoba Study, indicate that the weights associated with the greatest longevity tend to be below the average weights of the population as long as such weights are not associated with concurrent illness or a history of medical impairment.


Lee IM. et al. (1993). Body weight and mortality. A 27-year follow-up of middle-aged men. Journal of the American Medical Association, December 15, 270(23), pages 2823-8.
In 1993, the Journal of the American Medical Association published a study that concluded: "In these prospective data, body weight and mortality were directly related. After accounting for confounding by cigarette smoking and bias resulting from illness-related weight loss or inappropriate control for the biologic effects of obesity, we found no evidence of excess mortality among lean men. Indeed, lowest mortality was observed among men weighing, on average, 20% below the US average for men of comparable age and height.

Manson E. et al. (1995). Body wight and mortality among women. New England Journal of Medicine, September 14, 333(11), pages 677-85.
In 1995, a study published in New England Journal of Medicine concluded: "Among women who never smoked, the leanest women ... had the lowest mortality, and even women with average weights had higher mortality. Mortality was lowest among women whose weights were below the range of recommended weights in the current U.S. guidelines. Moreover, a weight gain of 10 kg of more since the age of 18 was associated with increased mortality in middle adulthood. These data indicate that the lowest mortality rate for U.S. middle- aged women is found at body weights at least 15 percent below the U.S. average for women of similar age.


Solomon CG. (1997). Obesity and mortality: a review of the epidemiologic data. American Journal of Clinical Nutrition, October, 66(4 Suppl), pages 1044S-1050S.
In 1997, the American Journal of Clinical Nutrition published a study on body weight and mortality stating: "We conclude that when appropriate adjustments are made for effects of smoking and underlying disease, optimal weights [for longevity] are below average in both men and women; this appears to be true throughout the adult life span.

[sjayo]

The study is correct -- the observed risk of death is not significantly higher in the overweight category (BMI between 25 and 30), but it is significantly higher in the obese category (30+) -- which is where a significant portion of the population is headed. However, these data do not compare death rates in the overweight category with people who are calorically restricted, so remember that the frame of reference is important. It is also important to remember that the lower death rates are attributable, in part, to better treatment of cardiovascular diseases. This means the saved population is more frail and disabled -- hardly a desirable situation. The bottom line -- lose the weight or don't cross over into the obese category.
Jay

[Live Forever]

The study is correct -- the observed risk of death is not significantly higher in the overweight category (BMI between 25 and 30), but it is significantly higher in the obese category (30+) -- which is where a significant portion of the population is headed.  However, these data do not compare death rates in the overweight category with people who are calorically restricted, so remember that the frame of reference is important.  It is also important to remember that the lower death rates are attributable, in part, to better treatment of cardiovascular diseases.  This means the saved population is more frail and disabled -- hardly a desirable situation.  The bottom line -- lose the weight or don't cross over into the obese category.
Jay

Thanks for the clarification, Dr. Olshansky. Good to see you back on the site as well. [thumb]

[resveratrol]

Much appreciated! Your reply really puts it in perspective.

[InquilineKea]

Are the poor significantly more likely to be underweight? (that could explain things). They are overrepresented among the obese - we know that for sure - but this just means that there are fewer of average weight among the poor
==

Anyways here's a post I made:

http://jama.ama-assn...ull/298/17/2028

So the question is, WHAT are they significantly more likely to die from?

chronic respiratory disease and injury are associated with increased deaths for the underweight. hm. but what ARE the other causes? A list of causes of death shows many causes that are attributable to “blood glucose level/cholesterol level/etc” related deaths - but few other causes (injury, chronic respiratory disease, parkinson’s maybe, but what else?)

And wrt chronic respiratory disease, “The major cause of chronic
lower respiratory disease is smoking; 80% to
90% of all patients with chronic lower
respiratory disease have a history of smoking.”

So, really, that’s not much of a concern. WHAT THEN IS of CONCERN?

“

Number of deaths for leading causes of death

Heart disease: 652,486

Cancer: 553,888

Stroke (cerebrovascular diseases): 150,074

Chronic lower respiratory diseases: 121,987

Accidents (unintentional injuries): 112,012

Diabetes: 73,138

Alzheimer’s disease: 65,965
Influenza/Pneumonia: 59,664

Nephritis, nephrotic syndrome, and nephrosis: 42,480

Septicemia: 33,373

Top 3 aren’t affected by being underweight. Still, it appears that most of the underweight don’t practice calorie restriction then. Calorie restriction should decrease 1, 2, 3, 6, 7, and 9. 4 is smoking-related. 5 is preventable, 8 is also preventable in part. And 10 is hard to quantify. But can non-cancer, non-CVD related deaths really increase the deaths by the underweight that much? the number of underweight is very small though, so it could be something not on the list. hmm. And I read the report - none of those causes can be attributable to the “OTHER non-CVD, non-cancer related deaths” (which explicitly listed chronic respiratory diseases, accidents, and influenza => none of which number among those deaths.) So it’s something else. What is that something else then?

http://avmajournals....ma.2000.216.347

==

Maybe the demographic trends would bring enlightenment. Maybe the underweight are significantly more likely to be poor (the obese are too, but this just means fewer poor of “normal” weight). And then the causes may be related to illness or malnutrition. Or SOMETHING. Just what IS that SOMETHING THEN?

of course, the underweight may have lost weight prior to death (and have died of another related cause). can that explain it all? the chart shows the underweight as having the highest death rates at ages 70+.

=
If you read http://jama.ama-assn...2028/JOC70112F3 , you'll find that they've listed pretty much ALL of the LEADING causes of death EXCEPT for Alzheimer’s disease and Septicemia (and CR effectively decreases Alzheimer's disease risk).

[krillin]

9 pound weight gain impairs endothelial function

The researchers recruited 43 lean, healthy volunteers from the community who each had a body mass index -- a statistical measure of the relationship of height to weight -- of between 18.5 and 24.9 kilograms of weight/meter2 of height. The average age was 29, and 42 percent were women. None took medications or smoked. After a weight maintenance period supervised by an experienced dietitian, volunteers randomly were assigned to either gain weight (4 kilograms [kg], or about 9 pounds) or maintain weight. The "fat-gainers" consisted of 35 people. The "weight-maintainer" group totaled eight.

Researchers used ultrasound to measure endothelial function of the large vessel in the upper arm called the brachial artery, under several flow conditions, always at the same time in the early morning. Low flow indicated vessel dysfunction. For the fat-gainers, endothelial function was measured at the start of the study, after fat gain at eight weeks and after weight loss at 16 weeks. For the weight maintainers, endothelial function was measured at the start of the study and at follow-up eight weeks later. To measure body fat percent, the researchers used advanced body composition analysis techniques, including abdominal CT scans.

Results

At the conclusion of the study:

    * The fat-gainer group put on an average of 4 kg of fat and significantly increased their visceral and subcutaneous fat.
    * In the weight-maintainer group, the two kinds of flow measurements taken in the brachial artery of the upper arm to assess endothelial dysfunction remained unchanged.
    * In fat-gainers, brachial artery flow measurements decreased with the addition of weight. But once subjects shed the gained weight their flow levels improved, and returned to levels measured at the beginning of the study.
    * Visceral fat gain -- but not subcutaneous fat gain -- was significantly correlated with the decreased flow conditions in the brachial artery.

This agrees with the recent story about winter weight gain making blood pressure harder to control.

http://www.imminst.o...=0

[Mind]

In most countries of the world the incidence of overweight and obesity in
humans has been rising steadily over the last 20 years.19 Overweight is a risk
factor for many diseases of old age and has a life-shortening action. Data from
the Framingham study show that at age 40 years being overweight (body mass
index [BMI] of 25–30 kilograms per meter squared) shortens life by 3 years,
and being obese (BMI>30) reduces life expectancy by 7 years.20 A study
of very obese subjects (BMI>45) aged 20–30 years revealed life shortening
EVERITT & LE COUTEUR 431
of 13 years for men and 7 years for women.21 Excess body weight may be
reduced by decreasing the intake of energy in food and by increasing physical
exercise to consume excess energy.22 Reduction of body weight decreases
the risk of developing type 2 diabetes mellitus, hypertension, coronary heart
disease, cancer of the uterus, breast, prostate and colon, and dementia.19 The
epidemic of overweight and obesity is predicted to become a serious threat
to our survival23 and as a consequence the continuing rise in life expectancy
through the years is expected to stop by the mid 21st century.23 Public health
measures are being developed to minimize the epidemic of overweight,24 but
it is very difficult to reduce body weight for long periods.

Life Extension by Calorie Restriction in Humans

* ARTHUR V. EVERITTaaCentre for Education and Research on Ageing, University of Sydney, and Concord RG Hospital, Sydney, NSW, Australia AND
* DAVID G. Le COUTEURaaCentre for Education and Research on Ageing, University of Sydney, and Concord RG Hospital, Sydney, NSW, Australia

Of course they then go on to say that the value of calorie restriction is not that great as compared to other societal health measures.

Abstract: Long-term reduction in energy intake in the diet (calorie restriction [CR]) extends the life of the laboratory rat by about 25%. However, in humans there are no life-long studies of CR, but only short-term trials which indicate that 20% CR acting over periods of 2–6 years is associated with reduced body weight, blood pressure, blood cholesterol, and blood glucose—risk factors for the major killer diseases of cardiovascular disease and diabetes. In addition, recent research has shown that CR for 6 months is able to improve biomarkers for longevity (deep body temperature and plasma insulin) and thus should increase life expectancy. The magnitude of the life-extension effect of CR in humans can only be estimated. The Okinawans, the longest-lived people on earth, consume 40% fewer calories than the Americans and live only 4 years longer. Similarly, women in United States consume 25% fewer calories than men and live 5 years longer. From the survival studies of overweight and obese people, it is estimated that long-term CR to prevent excessive weight gain could add only 3–13 years to life expectancy. Thus the effects of CR on human life extension are probably much smaller than those achieved by medical and public health interventions, which have extended life by about 30 years in developed countries in the 20th century, by greatly reducing deaths from infections, accidents, and cardiovascular disease.

[Matt]

The okinawa CR thing underestimates the power of CR in my opinion. Okinawans were only mildly CR'd for only half of their adult lives. Plus we know just how quickly health markers and gene expression can change from going from a CR to an ad lib diet. Check Spindler gene expression study on rodents. The okinawans have been steadily increasing their calorie intake since the 1960's.


Caloric Restriction, the Traditional Okinawan Diet, and Healthy Aging: The Diet of the World's Longest-Lived People and Its Potential Impact on Morbidity and Life Span.Willcox BJ, Willcox DC, Todoriki H, Fujiyoshi A, Yano K, He Q, Curb JD, Suzuki M.
Pacific Health Research Institute, 846 South Hotel Street, Suite 301, Honolulu, HI 96813. bjwillcox@phrihawaii.org.

Long-term caloric restriction (CR) is a robust means of reducing age-related diseases and extending life span in multiple species, but the effects in humans are unknown. The low caloric intake, long life expectancy, and the high prevalence of centenarians in Okinawa have been used as an argument to support the CR hypothesis in humans. However, no long-term, epidemiologic analysis has been conducted on traditional dietary patterns, energy balance, and potential CR phenotypes for the specific cohort of Okinawans who are purported to have had a calorically restricted diet. Nor has this cohort's subsequent mortality experience been rigorously studied. Therefore, we investigated six decades of archived population data on the elderly cohort of Okinawans (aged 65-plus) for evidence of CR. Analyses included traditional diet composition, energy intake, energy expenditure, anthropometry, plasma DHEA, mortality from age-related diseases, and current survival patterns. Findings include low caloric intake and negative energy balance at younger ages, little weight gain with age, life-long low BMI, relatively high plasma DHEA levels at older ages, low risk for mortality from age-related diseases, and survival patterns consistent with extended mean and maximum life span. This study lends epidemiologic support for phenotypic benefits of CR in humans and is consistent with the well-known literature on animals with regard to CR phenotypes and healthy aging.

PMID: 17986602 [PubMed - in process]


Caloric restriction and human longevity: what can we learn from the Okinawans?Willcox DC, Willcox BJ, Todoriki H, Curb JD, Suzuki M.
College of Nursing, Okinawa Prefectural University, 1-24-1 Yogi, Naha, Okinawa 902-0076, Japan. willcox@okinawa-nurs.ac.jp

Caloric (or dietary) restriction (CR) extends lifespan and lowers risk for age associated diseases in a phylogenetically diverse group of species. Whether prolonged CR increases average or maximum lifespan or promotes a more youthful physiology in humans at advanced ages is not yet known. However, available epidemiological evidence indicates that CR may already have contributed to an extension of average and maximum life span in one human population and appears to have lowered risk for age associated chronic diseases in other human populations. We review the human studies in the context of a special human population, older Okinawans, who appear to have undergone a mild form of prolonged CR for about half their adult lives.

PMID: 16810568 [PubMed - indexed for MEDLINE]

[gavrilov]

The study is correct -- the observed risk of death is not significantly higher in the overweight category (BMI between 25 and 30)...

This study says quite the opposite:

"...overweight was associated with significantly decreased all-cause mortality overall."

Please see study conclusions at:
http://jama.ama-assn...ull/298/17/2028

Hope it helps,

[sjayo]

Leonid
No, this doesn't help, it is inaccurate. There is a clear difference between overweight and obesity as stated unambiguously by the authors. Perhaps you should read the article a bit more carefully.
Jay

[spacetime]

In at least one of the studies showing the benefit of a higher BMI it was calculated postmortem. There are a lot of wasting diseases so to draw any conclusions from postmortem BMI is highly dubious.

[Harvey Newstrom]

Did they use the BMI at time of death, or before contracting the disease that killed them? Alzheimers can cause you to lose weight, for example.

This is a big question. A common mistake in these types of studies is to use the weight at the time of death. Since most people lose weight as they get sick and die, this skews deaths toward the lower-weight side. Studies that deliberately try to determine a person's average lifetime weight before the decline at death seem to find that lower weight is the healthiest. Many studies are unclear how or when they determined the deceased person's weight.

[biknut]

Chubby people live longest: Japan study

Health experts have long warned of the risk of obesity, but a new Japanese study warns that being very skinny is even more dangerous, and that slightly chubby people live longer.
People who are a little overweight at age 40 live six to seven years longer than very thin people, whose average life expectancy was shorter by some five years than that of obese people, the study found.

"We found skinny people run the highest risk," said Shinichi Kuriyama, an associate professor at Tohoku University's Graduate School of Medicine who worked on the long-term study of middle-aged and elderly people.

"We had expected thin people would show the shortest life expectancy but didn't expect the difference to be this large," he told AFP by telephone.

The study was conducted by a health ministry team led by Tohoku University professor Ichiro Tsuji and covered 50,000 people between the ages of 40 and 79 over 12 years in the northern Japanese prefecture of Miyagi.

"There had been an argument that thin people's lives are short because many of them are sick or smoke. But the difference was almost unchanged even when we eliminated these factors," Kuriyama said.

Main reasons for the shorter lifespans of skinny people were believed to include their heightened vulnerability to diseases such as pneumonia and the fragility of their blood vessels, he said.

But Kuriyama warned he was not recommending people eat as much as they want.

"It's better that thin people try to gain normal weight, but we doubt it's good for people of normal physique to put on more fat," he said.

The study divided people into four weight classes at age 40 according to their body mass index, or BMI, calculated by dividing a person's weight in kilograms by their squared height in metres.

The normal range is 18.5 to 25, with thinness defined as under 18.5. A BMI of 25 to 30 was classed as slightly overweight and an index above 30 as obese.

http://www.breitbart...;show_article=1

[Matt]

What has this got to do with CRON (Calorie Restriction with Optimal Nutrition).

They say that people tend to have fragile blood vessels? Well Fontana found that blood vessels of people on CR are much younger, some decades younger than people of their age. Also CRers report rarely getting sick of colds or flu, or if they do they quickly recover. My BMI is 16.4 and yes I did catch the flu in January (which can go onto pneumonia in some people), but it lasted just over 1 day and I was mostly better, with no lasting effects like a lingering cough or anything. Whereas my brother, sister, mother and father all had symptoms for 2 weeks or more and their BMI's range from 19 to 27

Edited by Matt, 19 June 2009 - 04:17 PM.

[Matt]

Also what was not mentioned in that article

"The study also found that the fatter a person is, the greater their medical expenses.

The average lifetime medical expenses for obese men from the age of 40 is 15.21 million yen ($195,000) and 18.6 million for obese women - both 30 per cent higher than for thin people."