Excess Pounds, but Not Too Many, May Lead to Longer Life | Hacker News Reader

Excess Pounds, but Not Too Many, May Lead to Longer Life

nytimes.com

5 pointstokenadult13 comments

The headline is designed to sound like a causation was established, when in fact the research can only point to a correlation.

People who are more sedentary probably just have higher incomes and therefore avoid other health pitfalls.

Why can't the MSM learn a bit of statistics?

> People who are more sedentary probably just have higher incomes and therefore avoid other health pitfalls.

You do actually have data to support your claim, right? (I don't know either way, but I'm not making any claims either.)

> Why can't the MSM learn a bit of statistics?

They're journalists.

Seriously, one day we read an article saying a diet "near starvation" will help us live longer and the next we read "excess pounds" is the way to go. The key is doing everything in moderation.

The trick in defining moderation is knowing what the extreme values are, which is why I find reports on optimal body mass indexes interesting.

The only way to run an experiment that could determine optimal BMI would be to lock up groups of randomly selected people in a jail-style environment for decades, where their diet could be accurately controlled. In other words, we'll never know the answer to this question for humans, despite what this article claims.

We've done these experiments in animals and those experiments suggest an extreme starvation diet leads to the longest lifespan.

I appreciate you mentioning the issue of experiment design in your reply. I enjoy posting in HN comments a link to Peter Norvig's article about that issue

http://norvig.com/experiment-design.html

which mentions some of the trade-offs involved in different forms of study designs.

The history of the prescribed drug Rimonabant (Acomplia)

http://en.wikipedia.org/wiki/Rimonabant

illustrates some of the problems with using animal studies to establish safety of interventions for human beings. The animal studies have to be done, and they are generally very helpful, but some aspects of human behavior are sufficiently complicated and not analogous to animal behavior that what looks safe and effective for animals turns out not to be beneficial for human beings.

Thanks for the great Norvig link

Again, body mass index is only a valid measurement if you know you're unhealthy (plenty of people are "athletic" but BMI tells them they're overweight). At that point, you don't need a semi-random telling you so. Body composition is a better measurement.

Except it seems like they're telling us moderation will kill you faster.

Here's a link to a body mass calculator that takes either customary United States measurements or metric system measurements:

http://www.nhlbisupport.com/bmi/

Strength is one of the best measures of health, especially as people age. Old people who are still strong will live a long time.

I suspect this study is just confirming that people with higher muscle mass live longer.

Do you have any facts or research to back this up? Beyond a certain baseline level of fitness, I would be pretty surprised to find out stronger means living longer. You would expect to see a lot more strongmen get to be over 80 years old if that was true.

There are a lot of old strongmen. Jack Lalanne, off the top of my head for one.

People die of old age when their lean body mass gets too low; when they look all skeletal. It's about that simple. The organs and muscles have wasted away too much and there's no power left. It makes perfect sense that people with more lean body mass will live longer. In contrast, endurance athletes are known to die young.

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...the Cooper Clinic in a paper published by Ruiz and co-authors found that cancer deaths are lowest in the strongest group.

Jonatan R. Ruiz and his co-authors tested more than 8,000 subjects aged 20 to 80 for muscular strength. They grouped individuals into three categories of strength and found that the age-adjusted risk of cancer was 17.5 per thousand in the weakest group, 11.0 in the middle group, and 10.3 in the strongest group. The weaker groups also had higher blood pressure, higher cholesterol, more cardiovascular disease, and more of them had diabetes. (Cancer Epidemiological Biomarkers Prevention 2009;18(5):1468–76).

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