I'd like to see this map juxtaposed with a map of the racial composition of each state. I think it would nicely illustrate how racialized the moral panic over fatness really is.

what should also be considered is that obesity rates change as the definition of obesity is changed.

I myself would be interested in how it coincides with the so-called Bible Belt. I come from one of the darkest states, and my first thought was to wonder if religious cultures' focus on the inner man might create a culture in which the outer man was of less importance, and maybe got less upkeep than he ought.

I'll also add that I myself am a bit overweight because the heat and humidity makes it very hard to want to take a walk outside. So... weather?

there are so many things that tick me off about reports like this.

for starters, they don't define "obese." i went to the website and looked through several pages to see if i could find what they defined as obese, and i didn't have any luck. but i'm going to guess that they used the incredibly flawed BMI system to show how many people are obese.

there is a fabulous slide show on shapely prose that has pictures of women and their BMI numbers. (it's here - http://kateharding.net/bmi-illustrated/ ) i don't think that most people realize what obesity looks like according to BMI. and of course, BMI doesn't take into account muscle mass.

but the biggest irritation i have with reports like this is that it doesn't talk about mortality rates or health issues. yes, they will mention type 2 diabetes. but they do not mention the extremely high connection type 2 diabetes has with genetics. it has an even stronger link with genetics than type 1 diabetes. (i'm so sorry, but i can't find the research on that right now. i know it's on junkfoodscience. sorry!)

there is also a huge assumption that being fat means you're unhealthy. but in reality, fat is not an indicator of health. there have been several studies about mortality rates and BMI, and only those in the highest ranges of BMI have a higher mortality rate than "normal" people. (they also are the smallest percentage of people.) people who are in the overweight category actually have lower mortality rates than those in the normal and underweight categories. but we never hear about that. it's just another "contradiction" that is chalked up to the obesity paradox.

to me, reports like this are just as useful as reporting that the percentage of people with brown eyes has gone up. (no idea if it has or hasn't. it's just an example.) people come in all shapes and sizes. i see this report as another scare tactic that will turn more people to dieting and/or weight loss surgery. both methods are more dangerous to health than simply staying fat. but again, that's something else you don't get to hear about.

oh, and the key point of this report is to show that obesity policies are failing in america. well... duh. as of yet there has not been a successful diet program or policy anywhere. (successful means that the weight is kept off. a staggering 95% of people who diet gain all of the weight back within 5 years, even if they stick with the diet.) but there is one thing that obesity policies are doing quite well. they are raising the incidences of eating disorders in our children. anorexia is the deadliest mental illness and has the lowest recovery rate. that is something that we really should be looking at, in my opinion. not how fat we are, but how our fear of fat is affecting the most impressionable among us.

I'd also love to see this data graphed vs. the populations' average ages. I'm quite interested in weight vs. age.

Has anyone made a map of the country with county data so poverty and obesity can be juxtaposed more precisely. I have a hunch there would be major overlaps... and what a great sociological image that would be!

As I thought. A bunch of fat chicks post here.

I don't understand the obsession with obesity. I suspect that the reason so much attention is paid to it is because of it's link to attractiveness, and not because of it's link to health. As is often stated in other posts it's inappropriate (although, I think, in some ways natural) to see other people's attractiveness as being for our benefit.

As hoshi points out above, obesity is only one factor that goes into determining a person's overall healthfulness, and it's only a controlling factor in extreme cases. Moreover, In the absence of an extensive socialized healthcare system to provide an economic incentive I don't see any substantial public interest in "fighting" obesity. Which leads me to believe people care about it because it's equivalent to saying "the people around us we have to look at are getting uglier"

Perhaps it does correlate with poverty, but in that case, why the interest in statistics on obesity. If poverty is the underlying problem, that's what deserves our attention. I don't mean this as a criticism of this post, but I see far more attention paid to "obesity" in the media than the attention paid to other indicators of health, or issues like poverty.

@ Duran
...and a few misogynistic, fat-phobic a-holes.

I would like to point out that
(1) The user name of every single poster above you is either gender-neutral of masculine;
(2) Add-hominem attacks on the previous posters in no way invalidate their arguments;
(3) You comment is, in fact, evidence for the implicit arguments that most of those posters are making: that our society is prejudiced against fat people--especially fat women.

See also: Moral Panic

The epidemiology of overweight and obesity: public health crisis or moral panic?
by Paul Campos, Abigail Saguy, Paul Ernsberger, Eric Oliver and Glenn Gaesser

Fat Panic: The Obesity Epidemic as Moral Panic
by Saguy, Abigail, and Almeling, American Sociological Association

Sandy Szwarc of Junkfood Science on the strong, persistent evidence that fat people live longer (and why you haven't heard these studies or why, when you have heard them, they're reported as "a paradox"):

More on understanding statistics and reporting on "the obesity epidemic:"

How an Obsession with Obesity Turned Fat into a Moral Failing
by Hannah Lobel

----

P.S. I think this the map posted above is an interesting one and good potential fodder for classroom discussion. But without introducing the context of moral panic alongside it, you would risk sanctioning fatphobia in the classroom and creating a fairly hostile environment for the fat students and for those students who may be thin and suffering from eating disorders.

There isn't much talk here about managing a classroom discussion using some of the material posted here, but I think it's worth thinking about how our the examples we bring into the classroom--alongside our own prejudices--can affect students in real and pernicious ways that they may not voice or even have the words to name for us.

(Pardon the stray words in my earlier post. I was typing with my 15 month on my lap, and he is worse than Chaucer's Adam for "helping" as I write.)

It is all. about. socioeconomic status.

Sociological Images: Fat chicks and one aggressively stupid troll.

"but i’m going to guess that they used the incredibly flawed BMI system to show how many people are obese."

I was going to say I don't know what else they could use but I gues they could use people's actual weights? I don't know if that would tell us anything more but people's weights aren't so disputable at least.

"i don’t think that most people realize what obesity looks like according to BMI."

Yes, I remember hearing news reports about how many people were overweight and obsese in Canada. I always thought really? I mean yeah, there are big people but it never seems like there are as many big people as those news reports make it sound like. I also wonder about the correlation with age. When looking at teenagers, if I were to worry about anything, I'd worry more about whether they're eating enough. But then the news would talk about overweight kids. I don't think it's changed that much since I was in grade school and I remember almost every kid being relatively the same healthy-looking size.

I've heard the 95% statistic before and I still find it hard to believe. When I see that people weigh less in countries where people are more active and eat better, it tells me weight isn't only genetics and maybe a permanent change in lifestyle could result in permanent weight loss. Of course lifestyle matters a lot less for some people who will be thin or fat no matter what they do.

"I don’t think it’s changed that much since I was in grade school and I remember almost every kid being relatively the same healthy-looking size."

It hasn't. What has changed is that the WHO lowered the criteria for these classifications quite dramatically in the 1990s, under pressure from a 'medical' group primarily funded by drug companies and weight-loss groups, which stand to make a killing (literally!) from the lowered thresholds.

"When I see that people weigh less in countries where people are more active and eat better, it tells me weight isn’t only genetics and maybe a permanent change in lifestyle could result in permanent weight loss."

Most people have a 10 to 20 lb range in which their weight can fluctuate based on 'lifestyle' factors (e.g., no exercise versus many hours a week, or carnivorous vs. vegan diet). Since the thresholds for 'overweight' and 'obese' are now so incredibly low, a few pounds average weight difference due to slightly different lifestyles is all it would take to push the percentage of people who meet these criteria up or down dramatically. Further, work has been done that suggests the 95% statistic is actually much too low, and that the number should be 98% or higher; an individual has to have an incredibly unusual physiology to not have his/her metabolism successfully adapt to a new diet or activity level, as the ability to regain and retain body weight under changing circumstances is an evolutionary must.

Hmm.... I notice a lot of fat children (5-10) but skinny teenagers, so I'm not sure if we really need to be so concerned about the 'age' of people who are fat.

I do feel a little sorry for the overly big children, though, I mean it seems to imply that they're participating in less family activities and it's a bit unfortunate for an 11yo girl to be requiring a C+ cup bra.

While the above posters are most likely right in saying that there's nothing too seriously bad about being a little overweight, I don't think it's a bad thing to be encouraging people to live active lives and keep themselves trim and fit. It seems to me that you're putting yourself at a disadvantage by gaining too much weight.

I do like Miriam's post - I hadn't considered how you would discuss this in a classroom without encouraging the 'fear of fat' and making weight-conscious students feel bad about themselves. Thanks for the insight :)

"I do feel a little sorry for the overly big children, though, I mean it seems to imply that they’re participating in less family activities and it’s a bit unfortunate for an 11yo girl to be requiring a C+ cup bra."

I'm not clear what's meant here. Are you suggesting that children are fat because they don't participate in family activities, or that they are somehow unable to participate in family activities because they are fat? (I've seen no evidence, statistical or anecdotal, of either.) As a fat child, and now as a fat adult, I certainly did/do not want pity, but rather the elimination of anti-fat bias and thin privilege, to allow everyone to live comfortably in the bodies they have.

"While the above posters are most likely right in saying that there’s nothing too seriously bad about being a little overweight, I don’t think it’s a bad thing to be encouraging people to live active lives and keep themselves trim and fit. It seems to me that you’re putting yourself at a disadvantage by gaining too much weight."

Please don't equate 'fit' with 'trim'. Fitness is a measure of ability to perform certain tasks, trimness is an aspect of appearance which is largely genetic 'luck' but which is systematically privileged in most societies, to everyone's ultimate detriment. Certainly, everyone involved in the size-acceptance movement would support engaging in enjoyable physical activities -- it's fun and healthy. But the suggestion that weight is an individual choice is offensive and misguided. Weight is no barrier to fitness or activity.

Is it possible that "Trust for America's Health" has a political agenda?

I spend every day helping people lose fat / get fit / etc..., but these reports about the Obesity Epidemic seem designed to scare people.

Fear is a great tool for driving public opinion & gov't policy

It would be better to have more information, such as the definition of obesity, and the BMI is a statistic that has to be considered in context, but from my own experience, more people are indeed getting heavier, and the extra weight is detrimental to them. They can't function physically and medical procedures are more difficult to recover from because of the weight.

Obesity is preventable for most people if they learn proper eating and fitness habits while young and particularly if they adjust their eating when they enter middle age. Most of the people I know who are very overweight simply refused to do that. They saw the weight piling on for years and did nothing.

It's important that public awareness be raised, just as with the the hazards of tobacco smoking.

Sue: http://kateharding.net/but-dont-you-realize-fat-is-unhealthy/

According to CDC data, the prevalence of obesity in the US has been steadily increasing in recent years* (while the definition has not been changed in that time span). It is safe to assume that this increase has not been due to people getting incredibly jacked. Could any of the supporters of fat/size acceptance in this thread enlighten me on these points:

1. Why have Americans, as a population, been getting fatter?
2. Will Americans, as a population, continue to get fatter? Why?

* http://apps.nccd.cdc.gov/BRFSS/display.asp?state=UB&cat=OB&yr=0&qkey=4409&grp=0&SUBMIT4=Go

The problem that seems to be cropping up is that the term 'obesity' is a catch-all term for a very diverse and distinct set of pathways to obesity or overweight--whether they are biological, social, psychological, or other.

I tend to lean toward the environmental health aspect as crucial to the issue (i.e. are there unknown/unseen metabolic changes going on within our bodies caused by the preservatives, growth hormones, pharmaceuticals, artificial additives, pollutants/carcinogens, etc. that are found in an alarming amount of our food & water supply.

@P: The standards changed in 1997; I'm not sure how far back you are including in "recent years."

@Eve: I mean the past decade; the linked graph imposes the new definition on data since 1995.

P, short answers to your questions:

If you look at the chart showing by Overweight, rather than by Obese, you'll see there's been virtually no change there at all.

Americans, just like every other nationality, are as a population getting fatter because we are also getting older, and weights increase with age.

Americans, just like everyone else, will continue to get fatter as a population because no one has found any way to change that natural inclination. The population will also continue getting taller, since we haven't found a way to change that, either.

For more information, check out the NYT on the genetic basis of weight:

"The researchers concluded that 70 percent of the variation in peoples’ weights may be accounted for by inheritance, a figure that means that weight is more strongly inherited than nearly any other condition, including mental illness, breast cancer or heart disease."

@ P:
1. Why have Americans, as a population, been getting fatter?
2. Will Americans, as a population, continue to get fatter? Why?

You're begging the question, here. Americans as a whole haven't gotten much fatter, but statistically speaking, it appear as if we have, as a matter of percentages.

Fat and Height (and their conflagration, BMI), like many naturally occurring phenomena, follow a bell curve. The arbitrary definitions for "overweight" and "obesity" were originally (~1940-50) placed at the 50th percentile and the 85th percentile of the BMI curve, respectively. A very _small_ change in weight translates into a very large change in percentage of people in those categories, as the large section of the curve moves ever so slightly. Even a change in both weight and height (because of the formula used to calculate BMI) can behave the same way.

In fact, that's what happened. Americans increased in both average height(2+ inches) and weight (6-15 lbs) during the last 30-40 years. Even without the changes in definition, it would appear to be a much bigger change than it actually is.

As to what caused this small shift: I would offer three possible explanations:

1. Like the rest of the century, nutrition and overall health improved during this time, allowing us to grow taller and larger.

2. The population during this time got significantly older, and weight gain with age is common.

3. The percentage of people who smoke has fallen dramatically, and inhaling stimulants is known to lead to unhealthy weight loss.

Those are only possible explanations, of course. Given that each of these things is true, however, it is interesting that we haven't, as a population, gained more weight during this time.

As to whether or not it will continue to increase indefinitely is unknown. If you accept any or both of explanations 2 or 3, it seems unlikely. All of these have natural end points: boomers will eventually die and the people who smoke will eventually bottom out at some small percentage. If the answer you accept is one, then it is unknown. We do not know the limits of nutrition, medicine, or if there exist any natural limits on human height and weight.

Hope this helps.

Thanks, Kaethe and pocket_owl. I think we should be more precise when talking about weight versus fat - and yes, the fact that "overweight" is almost always used interchangeably with "overfat" doesn't help.

You both write that Americans have gotten fatter because the population has gotten older, and weight increases with age. It would be more precise to say that, with a few exceptions, people gain fat as they get older. This, on its face, is a reasonable explanation for the trend: if people gain fat steadily throughout their lives, the longer they live, the fatter their population will be.

However, it does not explain why the prevalence of childhood obesity has also increased.* By definition, children don't get older from one cohort to the next. (To the best of my knowledge, they also aren't big on smoking.) So even though children were omitted from the dataset I initially cited, changes in the population's age and smoking habits don't account for all of the change in the prevalence of obesity.

I think pocket_owl makes a great point in noting that nutrition and health have improved drastically over the past century. As a small example, the physiques of old-time elite athletes are now attainable for millions of average Americans. Cheap food and the decline of infectious disease are undoubtedly important. But - bringing it back to definitions - it is equally important that what Americans have been gaining is largely fat, not lean mass.** We grew taller, but also wider. Why is that?

It would be interesting to see if BMI trends did settle into a pattern of logistical growth: this might happen if populations genetically couldn't get fatter beyond a certain point, or if society were unable to accommodate large numbers of people over a certain BMI.

* http://www.cdc.gov/obesity/childhood/prevalence.html
** There is little (no?) reliable historical data on body composition, but this seems a reasonable premise.

So I ask this because there are explanations here I haven't read much of before:

Why are people getting diabetes at younger ages?
Are there any articles or studies you know of that show the correlation of the increasing age of the population and increasing obesity? This explanation makes sense but I'd love to read more.
During the time we increased in height, BMI wouldn't have increased that much, right?

More needs to be done to regulate the food allowed in America. In Europe they have stronger laws for what food is and is not allowed. Also, maybe more could be done to promote the Farmer's Market throughout America. If getting fresh food became readily available, it may turn people away from the Fast Food.

Colorado is one of the skinniest states in the US. According to newsy.com, one of the reasons is because they have a health conscious society. http://www.newsy.com/videos/the_obesity_epidemic As a citizen originally from Arkansas, part of the reason for the health crisis is how people are raised to eat food. Fried food is a common diet there and it stems from times such as the Great Depression when food was scarce. People fried food to add more calories to their every day diet. Now it's a part of the culture.

As attention is increasingly focused on "the obesity epidemic," a survey by Harris Interactive(R) finds that adults who have been diagnosed as "obese" are much more likely to suffer from a broad range of diseases than the general population.
Those diagnosed with obesity are:

* 2.9 times more likely to have been diagnosed as diabetics (26% vs. 9%).

* 2.6 times more likely to have been diagnosed as having a sleep disorder

(21% vs. 8%).

* Twice as likely to have been diagnosed as suffering from depression

(32% vs. 16%).

* Twice as likely to have been diagnosed as suffering from back problems

(26% vs. 13%).

* Twice as likely to have been diagnosed with anxiety disorder

(20% vs. 10%).

* 1.9 times more likely to have been diagnosed as hypertensives

(41% vs. 22%).

* 1.8 times more likely to have been diagnosed with digestive disorder

(18% vs. 10%).

* 1.7 times more likely to have been diagnosed as having arthritis

(40% vs. 23%).

* 1.7 times more likely to have been diagnosed as having high cholesterol

(38% vs. 22%).

* 1.7 times more likely to have been diagnosed with migraine

(20% vs. 12%).

* 1.3 times more likely to have been diagnosed with allergies

(48% vs. 37%).

Overall, adults diagnosed as obese report that they have been diagnosed with an average of 6.4 chronic conditions, compared to an average of 3.1 conditions for those among the general adult population

Sorry about the long wait. I hope everybody had as nice a holiday weekend as I did.

@P:

I specifically did not say that Americans were getting fatter, as I do not think there is reliable evidence of any change in percent body fat, as you say, and feel we should not make assumptions about it. We do not know the composition of the small amount of weight that the American population gained, nor does the assumption that we gained body fat account for the height gain as well.

Childhood obesity is a harder question because much less (and much less history of) data is available to understand the trends. "Obesity" and "overweight" have only recently been defined for children, and the information we have on this is only in the last decade or so. During the first part of that time, children gained a small amount of both weight and height, and have since leveled off.

The increase in children's weights and heights can be attributed to the same factors as those for adults:

1. Increased nutrition and health play a role, and are as likely to affect children as adults. Perhaps more so, as the period of time when non-genetic factors play a role in determining adult height (and likely weight, although I know of little research) is concentrated in infancy and childhood.

2. It is possible for the age of the population as a whole to have an effect on heights and weights of children. People are having children at later ages and I do remember seeing a population study which correlated higher-weight babies with older mothers.

3. Second-hand smoke has a stimulatory effect on children.

4. There is also another reason I thought of since I last posted that might be considered as an explanation of increase in height and weight for the populations as a whole, including children, which is the increasing prevalence of non-white people in the US. Current statistics show that according to the arbitrary definitions, minorities are more likely to be "overweight" or "obese".

The question as to why we grew both taller and heavier at the same time confuses me a bit. The answer seems self-explanatory to me. To the small extent that height and weight are influenced by factors other than genetics (and twin studies show they are influenced by genetics by about the same amount), adequate nutrients and general good health in childhood both seem to influence those numbers higher. It seems as if you believe that growing both heavier and taller due to the same causes is somehow a contradiction.

@Lyndsay:

Why are people getting diabetes at a younger age?

I will assume you mean type II diabetes. We don't know that people _are_ getting type II diabetes at younger ages. First, there has been a change over time of diagnostic criteria from symptoms (which children do not, as a rule, exhibit) to serum blood sugar, and then to ever-lower blood sugar numbers. Second, there has been an increase in blood-sugar testing of the population as a whole, and the beginning of testing blood-sugar in children at all, a previously unknown practice except in very, very rare cases. Finally, children naturally go through periods of high blood sugar before a growth spurt, so even those cases that are found are suspect.

All of these can cause diagnosed cases to go up, without an actual increase in incidence.

Are there any articles or studies that you know of that show the correlation of increasing age of the population and increasing obesity?

During the time that information has been collected on height and weight in the U.S., both the average age of the American population and the average BMI have gone up. Strictly speaking, this constitutes a statistical coincidence and does not prove diddly and/or squat, but we don't need anyone else to do the comparing for us.

A more interesting comparison for these purposes would be to see if there exists a correlation between individual age and increasing weight, which has been done.

During the time we increased in height, BMI wouldn’t have increased that much, right?

No, actually. Remember that BMI is computed with the _square_ of height, so, e.g., a 10% increase in height will only decrease BMI by 1%, whereas a 10% increase in weight increases BMI by a full 10%.

Hope this helps,
pocket_owl

pocket_owl, you claim that "the information we have on [childhood obesity] is only in the last decade or so." In the link I cited above, the CDC summarizes data going back to 1971. By the looks of it, the incidence of obesity among children is accelerating, not leveling off.

My point on how Americans have been affected by nutritional changes over time is this: we have been able to get more calories, and more cheaply, from just about every conceivable source. Yet as the population has gotten taller, it has gained fat, not lean mass, suggesting that some factor is channeling the effect of improved nutrition into an increase in the prevalence of obesity. I do concede that neither of us can back up our (opposing) assumptions on this point with data.

At the end of the day, I fear you will not get far denying that Americans have been getting heavier (and, strictly speaking, fatter). That "small shift" of the normal curve of the BMI distribution you mentioned in your first post doesn't seem to exist. What seems to be going on is that at any point in time, some people are fat and others aren't (assuming plentiful food); and, over time, more Americans have become fat, and fat Americans have become fatter.

pocket_owl has done a better job at addressing these issues, but in the absence of same, I'll try to step in.

Yes, the CDC has data going back to 1971. But the NHANES data were not standardized. Most notably, prior to 2000, actual heights and weights were reported, rather than the more recent and meaningless BMI. (For more on this, no significant trends between 1999 and 2006. So, not accelerating, not increasing.

There is no evidence whatsoever to support your contention that increases in weight, along with height, are exclusively fat. What's more important perhaps, is, so what? Americans are also living longer than ever. Since most of humanity has never had the advantage of plentiful food, and since much of humanity still doesn't, we have no idea what being taller, and heavier, and healthier will mean for us.

Kaethe, thanks for the citation. It's funny how, when you look at childhood obesity trends from 1971 - 2000, you'll see an accelerating increase, but from 2000 to 2006, you'll see no change.

I also agree that as Americans' life expectancy has been hitting record highs, our understanding of the effects of increased BMI on populations' health remains incomplete. While obese Americans have been more likely to self-report ill health, and, as zoelouise wrote above, be diagnosed with various maladies, these are noisy, perhaps biased, indicators of true health.

Finally, on historical changes in body comp: no one has data on percentage bodyfat in representative samples from a century ago. Anecdotally, it is a common assertion that people have been getting fatter, not just bigger. (See, e.g., the discussion here). So while your skepticism is on point, it does not mean that we should default to the assumption that body composition has remained stable over time.

There are a lot of flaws with the data over time, and that's true of almost anything you want to look at having to do with human bodies. It's particularly true when looking at data such as the heights and weights of kids. Not that long ago, many women were vigorously policed for weight gain during pregnancy (25 pound limit, tops). Five pound babies were extremely common. Now a term baby is expected to be 7 pounds, and five at term indicates poor nutrition or a problem. It's all the way through. Anyone who thinks they have an answer for what should a 5-foot-tall ten-year-old weigh is wrong. While the growth charts may give docs an idea of children who are failing to thrive, there isn't anything in them about both parents being short and skinny, or tall and robust, let alone anything which makes sense of childrens' erratic growth patterns.

Ask yourself this: what is "true health" anyway? Is it a chronic but manageable condition? Is it trying to avoid diseases with a high genetic component? Is it feeling able to do whatever you want to?

As for body composition, my assumption isn't that it is stable from a century ago. My assumption is that it doesn't matter. And so far, no one has successfully proved that it does.

I'm not sure if we're still talking strictly about the effects of population body composition on population health, but as far as individuals go, body comp does matter when it comes to health outcomes. From a cursory Google search:

1. "Low lean mass was associated with greater impairment in symptoms [and] activity" among "patients with obstructive airways disease."

2. Among elderly women in one study, "a one-unit gain in lean mass:fat mass ratio reduced [self-reported functional] limitation."

3. In another study, "changes in body composition, as a consequence of dietary and exercise modification, contribute to 12% of the 'observed' improvement noted in weight-adjusted peak aerobic capacity following cardiac rehabilitation and exercise training."

4. "High BMI [hemodialysis] patients with inferred high body fat have increased and not decreased mortality, [with] the protective effect conferred by high BMI ... limited to those patients with normal or high muscle mass."

5. In a study of premenopausal women, "Fat and lean mass both independently predicted poor performance on postural stability, [indicating] that greater fat mass may compromise stability and, thus, increase fall risk in heavier individuals."

So in sum, body composition is kind of a big deal for individual health outcomes. Still, as I understand it, the data is insufficient to show the effects of changing body comp over time on the health of the general population.

On the individual level, I'm sure that body composition is important, but on the individual level, so is everything else.

You see the same obsession with weight in vets: a common cat lives on average 2 years if feral, 4-5 years if outside pet, 12-18 years as an indoor pet. As recently as 20 years ago, the life expectancy for a cat was only 6 years as an indoor pet. Clearly, we have no idea what the optimum weight or body composition of cats is, there is literally no precedent.

P,
higher fat mass does not mean lower lean mass. If that were the case, fat people would collapse under their own weight and one would not see them walking around.