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Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

nytimes.com

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Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#31

Post by [deleted] »

Retric wrote: post #29
wil421 wrote: post #12

Earlier quoted context omitted.

BMI is a horrible metric because it doesn't take body composition into account. I can't believe I was once almost considered obese with a body fat of less than 5%. 5'10" at 200-210.

Your heart does not care if it's supporting fat or muscle it must pump blood for both. Further skin and colorectal cancer are both surface area and don't care about fat vs. mussel. Metabolically muscle is worse as it needs more oxygen and fuel. Which is one of the reasons body builders can often die young from a heart attack.

[deleted]

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#32

Post by Dylan16807 »

Retric wrote: post #29
wil421 wrote: post #12

Earlier quoted context omitted.

BMI is a horrible metric because it doesn't take body composition into account. I can't believe I was once almost considered obese with a body fat of less than 5%. 5'10" at 200-210.

Your heart does not care if it's supporting fat or muscle it must pump blood for both. Further skin and colorectal cancer are both surface area and don't care about fat vs. mussel. Metabolically muscle is worse as it needs more oxygen and fuel. Which is one of the reasons body builders can often die young from a heart attack.

Your heart is going to care about how much you weigh but not how tall you are.

Those cancers are going to be mostly a function of height, not caring about weight for most people.

Neither of those is a reason to care about the ratio that BMI represents.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#33

Post by omegaham »

pkaye wrote: post #25
wil421 wrote: post #12

Earlier quoted context omitted.

BMI is a horrible metric because it doesn't take body composition into account. I can't believe I was once almost considered obese with a body fat of less than 5%. 5'10" at 200-210.

Who considered you obese? Also is it healthy to even have <5% body fat?

My employer had one of those physical checkups for a lowered rate on insurance. I'm 5'10", 215 pounds[1]. The doctor sighed and said that he was required to tell me that according to BMI, I was obese and should consider losing weight. We had a good laugh about it.

My body-fat percentage is definitely not 5%, though. My guess is that it's around 14-15%. Everyone drastically underestimates how low their body-fat percentage is, and I am not a bodybuilder. I lift heavy and like pasta.

[1] terrible picture of me from a few weeks ago for reference: https://i.imgur.com/42WFEyA.jpg

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#34

Post by Alex3917 »

nchelluri wrote: post #2

Interesting article. I don't know that I'd take too much to heart given some of the obvious caveats the author has been nice enough to make explicit, but it sounds like I'd be hard pressed to argue the suggestions contained within. For the tl;dr crowd: - written by a physician - people often think that heart disease is controllable by our actions whereas they feel that cancer is not - > people can’t change many risk…

For what it's worth, vigorous exercise is barely more than walking:

http://www.cdc.gov/physicalactivity/basics/measuring/heartra...

E.g. if you do an hour on the elliptical machine at 150 bpm then that's already 80% of your exercise RDI for the week.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#36

Post by eli_gottlieb »

nchelluri wrote: post #17
eightfourteen wrote: post #15

Earlier quoted context omitted.

BMI is a tool for doctors to use, along with clinical judgement. No doctor is going to look at a lean, well muscled individual and tell them they're at risk for heart disease because their BMI is high. BMI is something that fails in theory and works in practice.

when you record someone's BMI and it gets thrown in a spreadsheet as patient 123456 has BMI 23.5 the doctor is no longer looking at the patient. perhaps it's good enough, i don't claim to be able to evaluate the methodology of the study (and perhaps using BMI simply results in more skeptical results, by leaving healthy people out of the low risk group, which I'm fine with - not sure this is true though). it really wa…

They also record your blood-pressure measurements on the chart. If you've got a mildly high BMI and fine blood-pressure, they know you're actually ok.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#37

Post by parfe »

amock wrote: post #10
nchelluri wrote: post #2

Interesting article. I don't know that I'd take too much to heart given some of the obvious caveats the author has been nice enough to make explicit, but it sounds like I'd be hard pressed to argue the suggestions contained within. For the tl;dr crowd: - written by a physician - people often think that heart disease is controllable by our actions whereas they feel that cancer is not - > people can’t change many risk…

What's wrong with BMI for something like this? It's such a simple measure and it seems to be useful for predicting health issues. From what I've read body fat percentage is what really matters, but accurately calculating that takes expensive equipment. http://www.nytimes.com/interactive/projects/cp/summer-of-sci... seems to indicate that BMI does a pretty good job, although it may be too generous on the high end.

>What's wrong with BMI for something like this?

How many runners do you know who would complain about BMI? Or weight lifters? It's the fat people who don't like it.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#38

Post by Trundle »

eightfourteen wrote: post #15
nchelluri wrote: post #2

Interesting article. I don't know that I'd take too much to heart given some of the obvious caveats the author has been nice enough to make explicit, but it sounds like I'd be hard pressed to argue the suggestions contained within. For the tl;dr crowd: - written by a physician - people often think that heart disease is controllable by our actions whereas they feel that cancer is not - > people can’t change many risk…

BMI is a tool for doctors to use, along with clinical judgement. No doctor is going to look at a lean, well muscled individual and tell them they're at risk for heart disease because their BMI is high. BMI is something that fails in theory and works in practice.

I thought it was a tool for measuring large populations where the lean, well muscled outlier is heavily outnumbered/balanced out by their opposites. Either way though I agree that it's silly for individuals to try to apply it to themselves and then shit on the concept because it doesn't work like that.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#39

Post by dredmorbius »

coldtea wrote: post #19
sosborn wrote: post #14

Earlier quoted context omitted.

> It's such a simple measure and it seems to be useful for predicting health issues. It is good for predicting in general populations, but can easily fall apart with individuals. It doesn't take into account what the makeup of your mass is. Muscle is denser than fat, so a muscular man and a fat man of the same height and weight would have the same BMI, but vastly different health profiles.

> It is good for predicting in general populations, but can easily fall apart with individuals. While it can "easily fall apart with individuals", the difficulty lies in finding an individual to measure that will make BMI fall apart. And that's because the huge majority of us is of the kind of complexion and body type where BMI works well. So, sure it can give false positives, but for a quite small fraction -- beside…

The "individual measure" you're looking for is body fat percentage.

A vastly more accurate proxy is waist circumference.

BMI was developed largely because the proxy data (height and weight) are so readily available, especially in databases. Few doctors take waist measurements, and doing so is slightly more complicated.

Re: Helpless to Prevent Cancer? Actually, Quite a Bit Is in Your Control

#40

Post by dredmorbius »

eightfourteen wrote: post #15
nchelluri wrote: post #2

Interesting article. I don't know that I'd take too much to heart given some of the obvious caveats the author has been nice enough to make explicit, but it sounds like I'd be hard pressed to argue the suggestions contained within. For the tl;dr crowd: - written by a physician - people often think that heart disease is controllable by our actions whereas they feel that cancer is not - > people can’t change many risk…

BMI is a tool for doctors to use, along with clinical judgement. No doctor is going to look at a lean, well muscled individual and tell them they're at risk for heart disease because their BMI is high. BMI is something that fails in theory and works in practice.

https://news.ycombinator.com/item?id=12040933

"No person" is a rather extreme position.

Turns out some doctors are idiots, or frauds, or incompetent.

Turns out some just follow the protocol they're told to follow, even if they laugh at it (as in the link above, from this thread).

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