Optimal BMI - redux

[geo]

The latest study you present http://m.eurheartj.oxfordjournals.org/c ... rtj.ehw221 can be a bit disheartening to those of us that have worked hard to get down to the 21 BMI range, i.e., working for optimal health and life extension. For myself it was a lot of work to get there, thinking that I was doing about as good as I ccould. Now, it appears that maybe a little more work is in order. But better knowing now than later... and I enjoy a good challenge

I understand that the data shows only relative values as to health gain between the lowest level and the next, so it would have been more helpful to show absolute values, but it is what it is.

Whats not clear is if the data could be extrapolated to those of us of older age than the study's "teenage" group. Is it possible that as we age that it becomes even more important to get to that 18.5-20 BMI level? Do you know of any data that may give us a clue to this?

Another issue that bothers me is that these BMI levels never mention % Body Fat levels. I've always wonder why this is so and would one be healthier if they were at a BMI of 18.5-20 with 15% BF or with 10% BF? Of course the argument might be how did you achieve those BF levels, i.e., exercise, natural bone structure/body type, greater/lesser muscle mass, genetics, etc...

[JeffN]

The latest study you present http://m.eurheartj.oxfordjournals.org/c ... rtj.ehw221 can be a bit disheartening to those of us that have worked hard to get down to the 21 BMI range, i.e., working for optimal health and life extension. For myself it was a lot of work to get there, thinking that I was doing about as good as I ccould. Now, it appears that maybe a little more work is in order. But better knowing now than later... and I enjoy a good challenge I understand that the data shows only relative values as to health gain between the lowest level and the next, so it would have been more helpful to show absolute values, but it is what it is.

Whats not clear is if the data could be extrapolated to those of us of older age than the study's "teenage" group. Is it possible that as we age that it becomes even more important to get to that 18.5-20 BMI level? Do you know of any data that may give us a clue to this?.

I wouldn't stress to much over it. If you review all the articles in the Optimum BMI thread, there is no clear consensus that 20 or less is the ideal. Remember, these kind of studies are not able to show direct causal relationships, only casual relationships and associations. Yes, consistent associations over time, begin to show a picture but that picture must be further tested.

So, to me, this above study reinforces the overall message of the original thread, that if obtained through a healthy lifestyle and diet, that being in the lower range of the normal range, regardless if that is 18.5 to 20, or 18.5 to 22 or 18.5 to 19.5 etc. If I was in your shoes, I would not lose any sleep over an exact number but feel all the efforts I have made have put me in the right "area" without knowing the exact perfect spot (which doesn't exist).

Same as I explained in another thread, that a total cholesterol of </= 150 is not a guaranteed protection form heart disease.

I would also recommend you review this thread, where this topic came up earlier

viewtopic.php?f=22&t=46837&p=482749#p482749

Another issue that bothers me is that these BMI levels never mention % Body Fat levels. I've always wonder why this is so and would one be healthier if they were at a BMI of 18.5-20 with 15% BF or with 10% BF? Of course the argument might be how did you achieve those BF levels, i.e., exercise, natural bone structure/body type, greater/lesser muscle mass, genetics, etc...

Yes, these things can matter. Line up 100 men who are exactly your age, height and weight and they would all have different body types, looks, builds, and % body fat, etc. And, I have posted some info showing that excess weight (not excess within normal range) regardless if it is from extra muscle, may still have health consequences. However, for most Americans, especially the 73% who are overweight and obese, I doubt this is an issue. So, while BMI often gets knocked, there is virtually no data for the benefit of % body fat.

Remember, BMI is **only** a "marker" and a "screening" tool and not a diagnostic tool. As a screening tool, it has to be one that can easily be obtained. Height and weight require virtually no intervention and/or assistance. Most people know their height and weight and/or can easily step on one inexpensive piece of equipment and get both numbers fairly accurately (the old doctors scale which is used at many health screenings). Waist circumference, body fat % etc, starts bringing in more complexity, more technology, more expenses and less accuracy unless done by trained people in a consistent manner (where exactly do you measure waist circumference, or pinch the calipers, and how much tension on the measuring tape, etc etc).

There have been studies done that while these other two numbers are important, when they do BMI, waist circumference, waist/ht, etc, none of them come out to be a better predictor than BMI alone. So, the easiest way to screen a large population is BMI and that is why it is used.

So, at the screening, if you are outside the healthy zone, or close to it, or the screener thinks there may be an issue (body fat, etc), you would be recommended for further evaluation.

All of this information only reinforces my first comment above and the one in the linked thread...

In Health
Jeff

[JeffN]

Perhaps you can let out a sigh of relief

viewtopic.php?f=22&t=6916&p=538774#p538774

From a Meta study of ~10 million people. For those with BMI's around 20-22, perhaps getting to 18.5 is not always a good idea and perhaps 20-22 is best.

In Health
Jeff


Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents
The Global BMI Mortality Collaboration†
Published Online: 13 July 2016
(Full Text)
DOI: http://dx.doi.org/10.1016/S0140-6736(16)30175-1

http://www.thelancet.com/journals/lance ... 1/fulltext

Summary

Background
Overweight and obesity are increasing worldwide. To help assess their relevance to mortality in different populations we conducted individual-participant data meta-analyses of prospective studies of body-mass index (BMI), limiting confounding and reverse causality by restricting analyses to never-smokers and excluding pre-existing disease and the first 5 years of follow-up.

Methods
Of 10 625 411 participants in Asia, Australia and New Zealand, Europe, and North America from 239 prospective studies (median follow-up 13·7 years, IQR 11·4–14·7), 3 951 455 people in 189 studies were never-smokers without chronic diseases at recruitment who survived 5 years, of whom 385 879 died. The primary analyses are of these deaths, and study, age, and sex adjusted hazard ratios (HRs), relative to BMI 22·5–<25·0 kg/m2.

Findings
All-cause mortality was minimal at 20·0–25·0 kg/m2 (HR 1·00, 95% CI 0·98–1·02 for BMI 20·0–<22·5 kg/m2; 1·00, 0·99–1·01 for BMI 22·5–<25·0 kg/m2), and increased significantly both just below this range (1·13, 1·09–1·17 for BMI 18·5–<20·0 kg/m2; 1·51, 1·43–1·59 for BMI 15·0–<18·5) and throughout the overweight range (1·07, 1·07–1·08 for BMI 25·0–<27·5 kg/m2; 1·20, 1·18–1·22 for BMI 27·5–<30·0 kg/m2). The HR for obesity grade 1 (BMI 30·0–<35·0 kg/m2) was 1·45, 95% CI 1·41–1·48; the HR for obesity grade 2 (35·0–<40·0 kg/m2) was 1·94, 1·87–2·01; and the HR for obesity grade 3 (40·0–<60·0 kg/m2) was 2·76, 2·60–2·92. For BMI over 25·0 kg/m2, mortality increased approximately log-linearly with BMI; the HR per 5 kg/m2 units higher BMI was 1·39 (1·34–1·43) in Europe, 1·29 (1·26–1·32) in North America, 1·39 (1·34–1·44) in east Asia, and 1·31 (1·27–1·35) in Australia and New Zealand. This HR per 5 kg/m2 units higher BMI (for BMI over 25 kg/m2) was greater in younger than older people (1·52, 95% CI 1·47–1·56, for BMI measured at 35–49 years vs 1·21, 1·17–1·25, for BMI measured at 70–89 years; pheterogeneity<0·0001), greater in men than women (1·51, 1·46–1·56, vs 1·30, 1·26–1·33; pheterogeneity<0·0001), but similar in studies with self-reported and measured BMI.

Interpretation
The associations of both overweight and obesity with higher all-cause mortality were broadly consistent in four continents. This finding supports strategies to combat the entire spectrum of excess adiposity in many populations.



This is fairly consistent with an earleir one that was also on BMI vs. mortality for over 1 million people. It found that the lowest mortality was around BMI of 23.

Body-mass index and mortality in a prospective cohort of U.S. adults.
N Engl J Med. 1999 Oct 7;341(15):1097-105.
PMID: 10511607

https://www.nejm.org/doi/full/10.1056/n ... 0073411501

"In healthy people who had never smoked, the nadir of the curve for body-mass index and mortality was found at a body-mass index of 23.5 to 24.9 in men and 22.0 to 23.4 in women."


In Health
Jeff

[geo]

Thank you Jeff, hard to argue with 10 million study subjects world wide.

However, while my overall health has been tremendously improved via Dr McDougall's MWL and your guidance, I still feel I have a ways to go. Maybe not so much nutrition-wise anymore, but definitely fitness-wise. It amazes me how much potential the human body holds and I want to make the most of that potential at least within the context of optimal health...I think the next year or two for me will be very interesting.

[JeffN]

So, while BMI often gets knocked, there is virtually no data for the benefit of % body fat.

Body Mass Index, the Most Widely Used But Also Widely Criticized Index
Would a Criterion Standard Measure of Total Body Fat Be a Better Predictor of Cardiovascular Disease Mortality?
Mayo Clinic Proceedings, April 2016 Volume 91, Issue 4, Pages 443–455

DOI: http://dx.doi.org/10.1016/j.mayocp.2016.01.008 |

Abstract

Objectives
To examine whether an accurate measure (using a criterion standard method) of total body fat would be a better predictor of cardiovascular disease (CVD) mortality than body mass index (BMI).

Participants and Methods
A total of 60,335 participants were examined between January 1, 1979, and December 31, 2003, and then followed-up for a mean follow-up period of 15.2 years. Body mass index was estimated using standard procedures. Body composition indices (ie, body fat percentage [BF%], fat mass index [FMI], fat-free mass [FFM], and FFM index [FFMI]) were derived from either skinfold thicknesses or hydrostatic weighing. For exact comparisons, the indices studied were categorized identically using sex-specific percentiles.

Results
Compared with a medium BMI, a very high BMI was associated with a hazard ratio (HR) of 2.7 (95% CI, 2.1-3.3) for CVD mortality, which was a stronger association than for BF% or FMI (ie, HR, 1.6; 95% CI, 1.3-1.9 and HR, 2.2; 95% CI, 1.8-2.7, respectively). Compared with a medium FFMI, a very high FFMI was associated with an HR of 2.2 (95% CI, 1.7-2.7) for CVD mortality, with these estimates being markedly smaller for FFM (ie, HR, 1.2; 95% CI, 0.9-1.6). When the analyses were restricted only to the sample assessed with hydrostatic weighing (N=29,959, 51.7%), the results were similar, with even slightly larger differences in favor of BMI (ie, HR, 3.0; 95% CI, 2.2-4.0) compared with BF% and FMI (ie, HR, 1.5; 95% CI, 1.2-1.9 and HR, 2.1; 95% CI, 1.6-2.7, respectively). We estimated Harrell's c-index as an indicator of discriminating/predictive ability of these models and observed that the c-index for models including BMI was significantly higher than that for models including BF% or FMI (P<.005 for all).

Conclusion
The simple and inexpensive measure of BMI can be as clinically important as, or even more than, total adiposity measures assessed using accurate, complex, and expensive methods. Physiological explanations for these findings are discussed.

In Health
Jeff

[geo]

Interesting and timely for me However, all references to it seem to lead to a pay-wall One of its authors is Dr Carl Lavine whose famous for extolling the virtues of fitness even if it means carrying a little more fat...I've not read his last book, "The Obesity Paradox" but I will now so I can get a proper idea of where he is coming from.

In my searches, I think this study may also be important but unfortunately is also behind a paywall :

Body fat percentage, body mass index and waist-to-hip ratio as predictors of mortality and cardiovascular disease

http://www.pubfacts.com/detail/24966306 ... cardiovasc

Thank Jeff!

[JeffN]

Interesting and timely for me However, all references to it seem to lead to a pay-wall One of its authors is Dr Carl Lavine whose famous for extolling the virtues of fitness even if it means carrying a little more fat...I've not read his last book, "The Obesity Paradox" but I will now so I can get a proper idea of where he is coming from.

In my searches, I think this study may also be important but unfortunately is also behind a paywall :

Body fat percentage, body mass index and waist-to-hip ratio as predictors of mortality and cardiovascular disease

http://www.pubfacts.com/detail/24966306 ... cardiovasc

Thank Jeff!

Try this

http://sci-hub.bz/10.1136/heartjnl-2014-305816



This is why we have to look at at all the studies on a topic and put it all in perspective.

I don't disagree that waist to height ratio (WHtR). waist circumference (WC), Fat mass index (FMI) or Body Composition "may" have some better predictive value but we run into the above mentioned problem and that these are difficult to use as a screening tool as there are issues with them that don't exist with BMI. The main problems are 1) the ease of use and also 2) getting screeners and clinicians to accurately and consistently measure waist circumference, or percent body fat.

As an FYI, here is some data on WHtR, which also does a good job but you have to get an accurate waist measurement.

Taylor, Am J Clin Nutr 2010.
Comparison of BMI, WC, WHR and WHtR in predicting incident coronary heart disease in 4 UK cohorts. In men there was no difference in predictive value, in women WC and WHtR performed better than BMI.

Schneider, J Clin Endocrinol Metab 2010.
Compared these measures in 2 German cohorts for predicting a composite metric of incident stroke, myocardial infarction and cardiovascular death. Predictive value: WHtR > WC > WHR > BMI.

Browning, Nutr Res Rev 2010.
Systematic review literature on WHtR, WC and BMI as predictors of diabetes and CVD from 1950 to 2008. Predictive value: WHtR > WC > BMI.

Lee, J Clin Epidemiol, 2008.
Meta-analysis of 10 studies looking at WHtR and BMI in predicting hypertension, type-2 diabetes, and/or dyslipidemia. Predicitve value: WHtR > BMI.

in 2010, the company I work with in NYC did a complete analysis of their patient data comparing BMI, FMI, WC, WHtR. This was on 10's of 1'000s of our patients. Here is what we found (unpublished)

- Body composition data helps us understand U shaped association between BMI and all cause mortality if body composition is measured using a validated technology.

- Fat mass index is a stronger predictor of clinical results than body mass index.

- Fat mass index predicts clinical results even after control for waist circumference.

- Body composition data may be a useful tool to inspire better health behaviors in patients.

However, because of the reasons I stated above, we still continue to use BMI as the main tool due to ease, accuracy and consistency and when needed (as indicated), we will include body composition.

When I worked with WFM on their biometric screening, this same discussion came up to the science advisory board about which was the best metric to use. Again, BMI was chosen because of the above issues. I encouraged WHtR but the medical professionals on the board agreed that getting accurate waist measures in a screening is difficult.

In Health
Jeff

[geo]

Thank you again for the link and for all the other references as well. And I really appreciate the non-published study info as well.

[JeffN]

Combined associations of body weight and lifestyle factors with all cause and cause specific mortality in men and women: prospective cohort study.

BMJ 2016; 355 doi: http://dx.doi.org/10.1136/bmj.i5855 (Published 24 November 2016)
http://www.bmj.com/content/355/bmj.i5855

Abstract
Objective To evaluate the combined associations of diet, physical activity, moderate alcohol consumption, and smoking with body weight on risk of all cause and cause specific mortality.

Design
Longitudinal study with up to 32 years of follow-up.

Setting
Nurses’ Health Study (1980-2012) and Health Professionals Follow-up Study (1986-2012).

Participants
74 582 women from the Nurses’ Health Study and 39 284 men from the Health Professionals Follow-up Study who were free from cardiovascular disease and cancer at baseline.

Main outcome measures
Exposures included body mass index (BMI), score on the alternate healthy eating index, level of physical activity, smoking habits, and alcohol drinking while outcome was mortality (all cause, cardiovascular, cancer). Cox proportional hazard models were used to calculate the adjusted hazard ratios of all cause, cancer, and cardiovascular mortality with their 95% confidence intervals across categories of BMI, with 22.5-24.9 as the reference.

Results
During up to 32 years of follow-up, there were 30 013 deaths (including 10 808 from cancer and 7189 from cardiovascular disease). In each of the four categories of BMI studied (18.5-22.4, 22.5-24.9, 25-29.9, ≥30), people with one or more healthy lifestyle factors had a significantly lower risk of total, cardiovascular, and cancer mortality than individuals with no low risk lifestyle factors. A combination of at least three low risk lifestyle factors and BMI between 18.5-22.4 was associated with the lowest risk of all cause (hazard ratio 0.39, 95% confidence interval 0.35 to 0.43), cancer (0.40, 0.34 to 0.47), and cardiovascular (0.37, 0.29 to 0.46) mortality, compared with those with BMI between 22.5-24.9 and none of the four low risk lifestyle factors.

Conclusion
Although people with a higher BMI can have lower risk of premature mortality if they also have at least one low risk lifestyle factor, the lowest risk of premature mortality is in people in the 18.5-22.4 BMI range with high score on the alternate healthy eating index, high level of physical activity, moderate alcohol drinking, and who do not smoke. It is important to consider diet and lifestyle factors in the evaluation of the association between BMI and mortality.

[JeffN]

While this is a CR study, I think it shows the benefit of dropping from the higher end of the healthy BMI range >22, to the lower end of the range 18.5-22

In Health
Jeff

Significant Improvement in Cardiometabolic Health in Healthy Non-Obese Individuals during Caloric Restriction-induced Weight Loss and Weight Loss Maintenance.
Most J, Gilmore LA, Smith SR, Han H, Ravussin E, Redman LM.
Am J Physiol Endocrinol Metab. 2017 Dec 12.
doi: 10.1152/ajpendo.00261.2017. [Epub ahead of print]
PMID: 29351490

http://www.physiology.org/doi/abs/10.11 ... 00261.2017

Abstract
Caloric restriction (CR) triggers benefits for healthspan including decreased risk of cardiometabolic disease. In an ancillary study to CALERIE 2, a 24-month 25% CR study, we assessed the cardiometabolic effects of CR in 53 non-obese (BMI: 22-28 kg/m2) men (n=17) and women (n=36). According to the energy-balance method (doubly labeled water and changes in body energy stores), the 25% CR intervention (n=34) produced 17{plus minus}1% (mean{plus minus}SE) and 14{plus minus}1% CR after 12 and 24 months (M12, M24), resulting in significant weight loss (M12: -9{plus minus}0.5; M24: -9{plus minus}0.5, kg; P<0.001). Weight was maintained in the control group whom continued their habitual diet ad libitum (AL, n=19). In comparison to AL, 24 months of CR resulted in a decrease in visceral (-0.5{plus minus}0.01 kg; P<0.0001) and subcutaneous abdominal fat depots (-1.9{plus minus}0.2kg; P<0.001) as well as intramyocellular lipid content (-0.11{plus minus}0.05%; P=0.031). Furthermore, CR decreasedblood pressure (SBP: -8{plus minus}3 mmHg; P=0.005 and DBP: -6{plus minus}2 mmHg; P<0.001), total cholesterol (-13.6{plus minus}5.3 mg/dL; P=0.001) and LDL-cholesterol (-12.9{plus minus}4.4 mg/dL; P=0.005). HOMA-IR decreased during weight loss in the CR group (-0.46{plus minus}0.15, P=0.003), but this decrease was not maintained during weight maintenance (-0.11{plus minus}0.15, P=0.458). In conclusion, CR in normal weight and healthy individuals is beneficial in improving risk factors for cardiovascular and metabolic disease such as visceral adipose tissue mass, ectopic lipid accumulation, blood pressure, lipid profile, whereas improvements in insulin sensitivity were only transient.

In Health
Jeff

[geo]

I wish we could see the details of the study. I would be interested in how they determined the 25% CR. I also wish we knew what they ate.

The last couple studies you have mentioned show that nothing more than losing weight can have significant effects in terms of improving several metabolic/chronic disease markers. However they also show that not all of these factors are improved on a more permanent/long term basis simply via CR.

...whereas improvements in insulin sensitivity were only transient.

I suspect they probably were eating a SAD based CR diet. Which does show the power of simple weight loss. On the other hand, how much more improvement would we have seen following a 25% CRON program based on the MWL.

A questions on fat loss, Visceral, Subcutaneous, and Intramyocellular. Are these different types of fat lost in equal amounts during weightloss (by %) and are any of these types more or less important in overall health? I don't believe we can specifically target a particular type of fat to lose and thus ultimately its a mote point, but I'm curious.

[JeffN]

I wish we could see the details of the study. I would be interested in how they determined the 25% CR.

How to determine the exact CR is open to debate. Even the CR practitioners don't have any consensus of a standard way. I can tell you what I think may be the best way but it is not a standard everyone uses.

A questions on fat loss, Visceral, Subcutaneous, and Intramyocellular. Are these different types of fat lost in equal amounts during weightloss (by %) and are any of these types more or less important in overall health? I don't believe we can specifically target a particular type of fat to lose and thus ultimately its a mote point, but I'm curious.

It is very difficult to target specific fat loss. I would say the consensus opinion today is that it is mostly genetically determined where it is added and added first, and where it is lost and lost from first. However, it seems visceral fat is lost much faster then subcutaneous fat, which is good, because out of the 3, subcutaneous is the least harmful (which BTW, is what liposuction removes).

In Health
Jeff

[geo]

Asking you questions can be so frustrating. Why? Because they always make me think twice and then lead me down the path of having to ask a half dozen more questions after spending hours doing more research

How to determine the exact CR is open to debate. Even the CR practitioners don't have any consensus of a standard way. I can tell you what I think may be the best way but it is not a standard everyone uses.

Most definitely I want to hear what you think the best way to determine CR!

But let me state my thoughts on this first... CR claims to lengthen lifespan. I think that maybe true to some extent. However, I'm not yet convinced that CR can extend lifespan beyond the current thought of limit of ~ 120 yrs give or take 5 years. Now those limits are what we see in people that don't have optimal lifestyles as we currently recognize. So I think they have managed these feats simply through having the best of genetic pools. They are truly blessed. So can CR extend lifespan beyond the current limits for genetically gifted folks. Maybe. But we do know that if nothing else a better lifestyle WILL lead to better quality of life. Which in itself is a great boost to a long life.

But whats the best CR? Well I believe that the best easily usable standard for optimal health is maintaining a BMI in the lower range of healthy. Now doing that coupled to a diet/lifestyle that we also beleive creates the optimal environment for health would seem to be the best ticket for max lifespan and potential extension. That diet/lifestyle would be the McDougall Program in its MWL form along with your guidelines and recommendations.

So for me the best and simplist way to do CR is just to simply get to an optimal BMI for you and do it following the MWL, of course with the recommended levels of exercise. If any additional CR beyond that is needed to possibly further extend lifespan I believe it may not be realizable because you then get to the point where at even lower BMI levels you may not be able to stop constant hunger and no one will live with that for any length of time and be happy. Hunger I believe can be the real limiting factor to CR, not calories itself. And theres no better way to CR and not be hungry then what is taught here.

So for me, CR is about reaching optimal BMI combined with optimal nutrition (MWL) and optimal exercise to maintain a high quality of life. And of course your better off the earlier you start, but whenever you start your way ahead of the game then doing nothing or even just doing CR.

I guess I'm describing what some might call CRON.

[JeffN]

Asking you questions can be so frustrating. Why? Because they always make me think twice and then lead me down the path of having to ask a half dozen more questions after spending hours doing more research .

How to determine the exact CR is open to debate. Even the CR practitioners don't have any consensus of a standard way. I can tell you what I think may be the best way but it is not a standard everyone uses.

Most definitely I want to hear what you think the best way to determine CR!

This is one example from someone who was in the CR Group for many years.

http://www.scientificpsychic.com/health/cron1.html

http://www.scientificpsychic.com/health/cron2.html

This one is from Michael Rae, a longtime practitioner or CRON
https://www.crsociety.org/topic/12481-h ... t-cr-am-i/

You explain my perspective in your comments below.

There are also some bio markers they check for.

But let me state my thoughts on this first... CR claims to lengthen lifespan. I think that maybe true to some extent. However, I'm not yet convinced that CR can extend lifespan beyond the current thought of limit of ~ 120 yrs give or take 5 years.

This is the difference between maximizing our existing potential (squaring the curve) and extending that potential (squaring and extending the curve). In animals, both have been shown. In humans, only one with possible potential of the second.

My guess is that if it does extend it, it will be a minimal amount. But, considering so many of us die prematurely of preventable illness, I think the first one, squaring the curve, is the one that is most important and the one more people will be interested in.

But whats the best CR? Well I believe that the best easily usable standard for optimal health is maintaining a BMI in the lower range of healthy. Now doing that coupled to a diet/lifestyle that we also beleive creates the optimal environment for health would seem to be the best ticket for max lifespan and potential extension. That diet/lifestyle would be the McDougall Program in its MWL form along with your guidelines and recommendations.

I agree, 100%. It is also the simples, easiest, most affordable and most accessible way to go about it.

If any additional CR beyond that is needed to possibly further extend lifespan I believe it may not be realizable because you then get to the point where at even lower BMI levels you may not be able to stop constant hunger and no one will live with that for any length of time and be happy. Hunger I believe can be the real limiting factor to CR, not calories itself. And theres no better way to CR and not be hungry then what is taught here.

Agreed.

Many of the longterm CR practitioners are highly disciplined, highly intelligent and highly motivated and for whatever reason, male.

So for me, CR is about reaching optimal BMI combined with optimal nutrition (MWL) and optimal exercise to maintain a high quality of life. And of course your better off the earlier you start, but whenever you start your way ahead of the game then doing nothing or even just doing CR. I guess I'm describing what some might call CRON.

CR Is actually just a shortened form of CRON, which some call CRAN (adequate not optimal).

In Health
Jeff

[geo]

There are also some bio markers they check for.

I'm interested in what biomarkers you consider to be most important to potentially determining overall health. I fully understand that no one or two biomarkers can determine health and that they are markers of potential disease and not the disease itself. Still, if you were focusing on a particular set of biomarkers that may best represent a potential state of health what might they be? I know I'm leaving this wideopen to interpretation by not mentioning simplicity/complexity of measurements, values/ranges, potential accuracy, cost, standardizations, etc...)

My choice of bio markers (that anyone can do) would be:

1. Diet
2. Exercise
3. BMI

and then possibly follow that up with a full spectrum, comprehensive blood test of a wide variety of markers.