BMI of 25-29.9 showed the lowest rate of All Cause Mortality

[Will Morris]

Systematic Review and Meta-Analysis published in the Journal of the American Medical Association shows with strikingly good evidence a "high BMI"(25-29.9) showed the lowest rate of All Cause Mortality. It had an even lower rate of ACM than low and extremely low BMI.

Unfortunately, I am unable to post the entire article at this time, but after going over the article, the reported stats in the abstract match up with what the article said.

http://jama.jamanetwork.com/article....icleid=1555137

[Mark Rippetoe]

And this comports pretty well with what we already know -- "we" meaning us cool people on this board.

[Will Morris]

And this comports pretty well with what we already know -- "we" meaning us cool people on this board.

Didn't someone once say, "Strong people are harder to kill than weak people"?

But what "we" know has now been supported by a Systematic Review / Meta-Analysis (the highest level of evidence) of 97 studies with a sample size of 2.8 million people. Then, it was published in the JAMA, but somehow, I am afraid healthcare providers will somehow lose the importance of the conclusions of this study.

[Subsistence]

I am not sure if they controlled for this but many medical conditions can result in weight loss. It could be that those who have things such as cancer could be more likely to show up in the "normal weight" group, giving them a worse prognosis.

[Mark Rippetoe]

Then, it was published in the JAMA, but somehow, I am afraid healthcare providers will somehow lose the importance of the conclusions of this study.

More importantly, it will continue to be ignored by the Insurance Companies of America, who delight in assigning elevated risk to people of normal healthy bodyweight.

[Jonathon Sullivan]

Filed and slated for review. THanks, William.

[wes]

I am not sure if they controlled for this but many medical conditions can result in weight loss. It could be that those who have things such as cancer could be more likely to show up in the "normal weight" group, giving them a worse prognosis.

The abstract states that they did not include studies that focused on people with specific conditions and people undergoing specific procedures.

I'd think that would eliminate most of the bias. Are there really enough people emaciated from cancer who are having their bmi's recorded in studies that aren't about cancer? I don't really know but I'd assume not.

I'm more interested to hear about how they controlled for age. My understanding is that bmi generally increases through middle age then tends to trend down as you get very old (due to loss of muscle and bone density?). Very old people are obviously more likely to die at any given moment so if they also tend to have a lower bmi than middle age people this could impact how relevant the results are to not-very-old people.

Does the actual article show mortality rates for bmi's for specific age groups?

[Subsistence]

The abstract states that they did not include studies that focused on people with specific conditions and people undergoing specific procedures.

I'd think that would eliminate most of the bias. Are there really enough people emaciated from cancer who are having their bmi's recorded in studies that aren't about cancer? I don't really know but I'd assume not.

I'm more interested to hear about how they controlled for age. My understanding is that bmi generally increases through middle age then tends to trend down as you get very old (due to loss of muscle and bone density?). Very old people are obviously more likely to die at any given moment so if they also tend to have a lower bmi than middle age people this could impact how relevant the results are to not-very-old people.

Does the actual article show mortality rates for bmi's for specific age groups?

Well, when we are dealing with old people dying it is likely they have some conditions, and cancer is a pretty top killer. Types of COPD can leave people quite frail, as can infectious diseases, etc.. I would think these people would show up in all cause mortality studied at a similar rate to which they show up in people dying in the general population. Which is to say reasonably often. Cancer is the second leading cause of death in the USA.

[Subsistence]

Wish I could edit, but to clarify.

Removing studies focusing on specific conditions prevents those conditions from being overrepresented in the study population. But if these conditions are more prevalent in some BMI ranges then others, then the aforementioned removal of studies does nothing to control for this (nor does it intent to). In fact, detecting such things would be part of the purpose of the study. Unfortunately unlike obesity contributing to a heart attack, the relationship is reversed with conditions like cancer contributing to weight loss (opposed to vice versa).

[Memdoch]

Cigarette smokers.