
The underappreciated role of muscle in health and disease [pdf] - fasteo
http://ajcn.nutrition.org/content/84/3/475.full.pdf
======
Mz
_However, over the past few years it has become evident that changes in the
metabolic function of muscle itself plays a more direct role in the genesis of
insulin resistance than previously appreciated._

This makes logical sense. Given that people with CF do not process fats
correctly, tend to be severely underweight yet are highly prone to developing
CF Related Diabetes, fat just about can't be the right explanation as to
cause.

On the other hand:

 _The central thesis of the glucose–fatty acid cycle is that elevated plasma
FFA concentrations limit glucose uptake in muscle by inhibiting the oxidation
of glucose (33). Thus, according to this theory, the genesis of insulin
resistance lay entirely with the increased availability of FFAs, and the
muscle responded normally to that signal to limit glucose uptake and
oxidation._

Can anyone tell me: If you are chronically insufficiently oxygenated for some
reason (like lack of lung function), would that contribute to this process? I
mean, it sounds to me like insufficient oxygenation of the system would play a
role here.

Any takers?

------
7Figures2Commas
This is a good example of why the focus on developing magic pills that aim to
curb obesity is so silly[1].

Body composition and strength are just as important, if not more important,
than weight, especially as one ages. The reason this is ignored is that
there's only so much you can do to significantly improve your body composition
and strength without exercise and healthy eating.

> Nonetheless, the maintenance of adequate muscle mass, strength, and
> metabolic function has rarely, if ever, been targeted as a relevant endpoint
> of recommendations for dietary intake.

It's kind of sad that the "official" recommendations basically ignore what
even the most inexperienced personal trainer could tell you.

[1]
[https://news.ycombinator.com/item?id=8736567](https://news.ycombinator.com/item?id=8736567)

~~~
jessriedel
A magic pill that could curb obesity would deliver hundreds of billions of
dollars worth of improved health outcomes in the US, regardless of whether
getting everyone to put on more muscle would be preferable. (And that's not
even accounting for the fact that people who hate exercise lose utility even
if you can convince them to do it.)

~~~
7Figures2Commas
You seem to be assuming that the health conditions and costs commonly
associated with obesity are all primarily _caused_ by obesity. I'd suggest you
consider the possibility that obesity is just as likely to be a symptom of
poor health as it is to be the cause of it. On this point, there are plenty of
people who aren't obese who have cardiovascular disease, diabetes, etc.

There's a lot we don't know about the human body, but based on what we do
know, it's asinine to believe that folks can eat horribly and live sedentary
lifestyles without serious consequence. That, however, is what magic pill
research effectively promises.

~~~
jessriedel
> I'd suggest you consider the possibility that obesity is just as likely to
> be a symptom of poor health as it is to be the cause of it.

I gladly acknowledge that possibility, but you should acknowledge the
likelihood that the medical community is roughly correct in its belief that
obesity does in fact cause a huge number of health related problems
_regardless_ of whether this is "primary". My claim above does not rest on
obesity being the dominant factor.

> it's asinine to believe that folks can eat horribly and live sedentary
> lifestyles without serious consequence.

Misunderstanding someone's claim and then suggesting that their beliefs are
asinine is not a good way to get people to engage productively with you.

~~~
7Figures2Commas
First, please don't pretend that the "medical community" is a homogenous body
that produces broad consensus on complex matters. There is and always has been
a significant amount of debate amongst medical professionals on a variety of
topics.

The topic of cholesterol provides many examples of this. For years, it was
widely believed that raising the levels of HDL cholesterol would reduce the
risk of heart disease. On that belief alone, many doctors regularly prescribed
niacin to patients. Yet a few years ago, a study basically revealed that while
niacin did raise HDL levels, it didn't reduce heart disease risk[1]. What's
worse, more recent studies have revealed that niacin may have exposed patients
to unacceptable risk[2].

To be clear: if you were ever diagnosed as having low HDL cholesterol, there's
a good chance that your doctor would have recommended that you consider a
treatment that not only would have been ineffective but exposed you to risk.
All based on a widely-promoted hypothesis we now have ample evidence is
flawed.

On the topic of obesity, there is growing evidence that obesity is not the
cause of a significant number of the most expensive health problems thought of
as being caused by or strongly associated with obesity. Take Type 2 diabetes.
Recent studies[3] show that it's a very complex condition, and genetics likely
plays a more significant role than thought. Somewhat disturbingly, a
longitudinal study published last year in the New England Journal of Medicine
found that "An intensive lifestyle intervention focusing on weight loss did
not reduce the rate of cardiovascular events in overweight or obese adults
with type 2 diabetes." That calls into question the notion that even weight
loss is a panacea for Type 2 diabetes.

You may not like my use of the word asinine, but if you're going to suggest
that a magic pill for obesity "would deliver hundreds of billions of dollars
worth of improved health outcomes in the US," you should at least have some
evidence to back it up. To do that, however, you have the very high barrier of
establishing that a) obesity in meaningful part causes the costly conditions
promoted as being obesity-related and b) reduction of obesity would provide a
significant enough benefit to eliminate a meaningful portion of the costs
associated with these conditions. More and more research shows this is not the
case.

[1]
[http://www.nytimes.com/2011/05/27/health/policy/27heart.html](http://www.nytimes.com/2011/05/27/health/policy/27heart.html)

[2] [http://www.cbsnews.com/news/taking-niacin-for-the-heart-
may-...](http://www.cbsnews.com/news/taking-niacin-for-the-heart-may-pose-
serious-health-risks/)

[3] [http://consumer.healthday.com/diabetes-
information-10/misc-d...](http://consumer.healthday.com/diabetes-
information-10/misc-diabetes-news-181/obesity-isn-t-sole-cause-of-
type-2-diabetes-691898.html)

[4]
[http://www.nejm.org/doi/full/10.1056/NEJMoa1212914](http://www.nejm.org/doi/full/10.1056/NEJMoa1212914)

------
IndianAstronaut
Interesting, I never realized muscle played a role in helping recover from
critical injuries such as head trauma.

------
NIL8
There are several interesting aspects of this article, but it could have used
a little more editing. As I read through, I can hear my 7th grade English
teacher saying, "structure and grammar." This lack of attention to detail
makes me wonder what else might have been overlooked in the study.

------
mrfusion
So would this imply men should be healthier than women? Body builders
healthier than other types of athletes?

~~~
fasteo
I don´t think the article is proposing "the more, the better". Rather, it is
emphasizing that muscle mass is much more that pure force production or
aesthetics in that it plays a key role in maintaining a healthy metabolism.

Replying to your question: if you compare two identical women differing only
in their percentage of muscle mass, yes, one is healthier than the other.

As for the body builders; this is a tricky question, but I don´t think they
are healthier than the general population...muscle mass being completely
irrelevant.

~~~
sillysaurus3
_if you compare two identical women differing only in their percentage of
muscle mass, yes, one is healthier than the other._

Depends what you mean by "healthy." Plenty of overweight people live long
lives.

I don't think anyone would disagree that muscles are desirable and that
exercise helps, or that being overweight is a bad thing. But there's quite a
lot of disagreement about the severity of the problem. If you look around,
there are many old and overweight people. They got to that point without
having the kind of muscle mass you're talking about.

A more persuasive approach is probably to focus on the benefits, rather than
the implied downside of not having "health." For example, I had no idea that
exercise would have such a profound effect on my brain. My mind is sharper
when I exercise compared to when I don't. At least, it was true for me. Could
be placebo effect, but, then again, the placebo effect is measurable, so
sometimes it helps.

~~~
cma
He meant statistically, he didn't mean that a pairwise comparison of all
females would provide no counterexamples.

~~~
sillysaurus3
I'm talking about the definition of "health." "Health" isn't a precise term.

