One does not simply overcome bias.

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This is ridiculous. As many commenters have pointed out, there are any number of reasons why poverty might and does cause obesity and a good number of others in which it'd cause the opposite.

When I was a poor student I ate a lot more fast food but when I had little money left till the end of the week I bought discounted, unhealthy but small ready-meals. The former behaviour piled it on whilst the latter was portion control.

Now I spend as much money as I like on food generally (i don't exactly like to invest it wisely) and yes it does include days with too many packs of crisps (potato chips to you) and never a cheeseless fridge but there's also much less of a psychological need for fast food now that I don't feel so out in the cold, less in need of comfort. Plus smoked salmon tastes so good. This is the thing. I once treated a girlfriend to a fancy restaurant and we ate every bite so slowly and with so much pleasure that she said "Now I know why rich women are thin. It's so delicious you almost don't care if there's only a little"

There's certainly a strong overall correlation in Britain but for us it seems obvious why it might not be so clear cut in the US. Your portions are huge. I was stunned at how much KFC a little money could buy you. The whole cheery hospitality thing you have over there is brilliant but nothing says "you're welcome" better than a well piled plate.So if you're well off enough to regularly dine out at the kind of TFI Friday tier, you'd struggle to maintain your weight. 

Clearly the question needs to be broken down into smaller parts but poverty does cause obesity and so does being well off.

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I think the generalization comes from the fact that the more obese states are those with lower incomes and higher percentages of minority population, therefore the conclusion that the poor and racial minorities are more likely to be obese.

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I am unswayed by your interpretation of the data, or the data as laid out. First, BMI is a terrible metric for measuring who is "fat." Only body fat percentage can truly assess whether a person is fat or not. I am 6'1" and 190 pounds. My BMI is 25.1. By definition in this study and many other studies on obesity, I am overweight. I also have 7% body fat. I am definitionally not overweight. By aggregating datapoints such as myself into studies like this, there is inherent bias in the measured variable. This is a fault of BMI as a metric.

Second, I need a explanation as to why Mississippi and West Virginia are both 1) the poorest states in the US, and 2) the hightest BMI states in the US (thought as previously noted BMI is a terrible measure of fat) before I reject that there is no correlation between poverty and obesity, since there are barely any demographic similarities between the two states.

Second, part A - why is Type II diabetes more prevalent amongst the poor?

Third - the argument from a public health standpoint is not that the poor can't afford healthy diets, its that the caloric content of many food products has an inverse relationship to price. Per calorie costs of an apple are much higher than that of Cocoa Puffs. If you are shopping for food on a limited budget, you get more bang for your buck in calories (and, theoretically, satiation) by purchasing these inverse relationship products.

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Next up, can we test the ridiculous bias that the poor are poor because they don't want to work?

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Believing in Hell, and therefore believing in the eternal justice of punishment, leads parents to mercilessly force their children to finish what's on their plates.http://www.jochnowitz.net/E...

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It is still widely accepted that the poor are lazy and that's all I care about.

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"After controlling for all other attributes that contribute to wages (an individual’s job experience, firm size, region in which they reside, occupation, sector, full or part-time employment, health, education, age, and whether or not they have young children) the author finds that married men and single women both have a wage rate that is positively related to the their Body Mass Index (BMI) – the heavier they are, the higher the wage they are paid. Single men and married women have the opposite experience – they are penalized for their weight -- the heavier they are, the lower the wage they are paid.<"

(Emphasis mine. Source)

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That is my impression as well, Robbie. The data suggest there is nothing here. There are plenty of fat rich people, and also plenty of fat poor people. As well, not just the summary statistics but the overall distributions look very similar.

The data suggest that BMI is predominantly driven by biology, by aspects of humanity that we are born with.

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That is not correct. You need to consider the price per calorie, not the price per unit weight.


Baby carrots cost $2.50 per 200 calories. Broccoli costs $1.93.

For what you would spend on 200 calories of carrots you could get 2,000 calories of glazed donuts.

People need to eat a certain number of calories per day, not a certain weight of food. If you need to eat 2,000 calories per day on a minimum budget, you are going to try and maximize consumption of things with low cost per calorie. Of the low cost sources of calories that do not require lots of preparation, cooking, refrigerated storage are all junk food.

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I agree that is way to address he question. Carrots and bananas are delicious and cheap. Cabbage, Collard and mustard greens are very cheap, I like them but not everyone does. It seems to me that their are plenty of cheap fruits and vegetables.

I think that causation might run the other way that is very fat and very skinny people have trouble find and holding good jobs, that could be because of their appearance or there could be a common cause.

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I think the paper is trying to say the opposite of how you're trying to interpret it.

The paper brings up that the poor (defined by 130% of poverty line) are not necessarily overweight (defined by BMI > 25), but then rejects that as a useful statistical measure and says it's too simplistic. It then proposes its own better statistical measures which show the expected correlation, and concludes:

"The regression analysis provides further evidence that the relationship between BMI and income is more closely linked to conventional wisdom than is suggested by the cross-tabulations...this paper provides evidence that the cross tabulation of overweight and poor provides a very incomplete picture of the relationship between income and BMI by indicating essentially no association between poverty and overweight and obesity status. Making policy decisions based on this though would make for poor choices. The UQR estimates further suggest that there...is a negative income gradient for the obese (much larger in magnitude than that estimated by OLS) which matches the standard health and wealth gradient, and conventional wisdom. "

So the conclusion of the paper says several times that the conventional wisdom of poor people being fatter is correct. As such, I find your title "The Poor Are Not Fat" to be either misleading or dishonest, without even getting into the other data that does find a simple discrete relationship between the two categories (eg here: "More than 33 percent of adults who earn less than $15,000 per year were obese, compared with 24.6 percent of those who earn at least $50,000 per year.")

Whether the poor are fatter or not probably depends on how you define "fat" - the study showed no difference ever in > 25 BMI, historical but not current difference in > 30 BMI, and I am guessing that you would currently find a difference if you looked at > 35 BMI. It may be that middle class society has "caught up" to the poor in the former two groups, but if you want to look at people who are fat, not just by doctors' standards but by the standards of society, the poor will still be disproportionately represented.

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I may be reading it incorrectly but that (very poor) graph seems to show poor and non-poor populations having very similar BMI distributions, sure the poor curve is slightly flatter but the difference is minimal.

Anyone care to point out where I'm incorrect?

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There is another problem with the cheap food, poor people hypothesis: Food price does not correlate with how healthy a food is. A more likely culprit is stress. Poor people tend to be more stressed than the wealthy and they can make unhealthy food selections in attempts to self-medicate through comfort foods or stress and depression can also lead to loss of appetite.

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...or not having time to cook, because you've got too many obligations. Having no or very limited kitchen facilities. Not being able to afford tasty healthy food, and not wanting to live a life eating food that doesn't taste good.

It's fun to pick all the morally blameworthy reasons, but not all the actual reasons are morally blameworthy.

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Interesting idea that the poor are fat because they have low impulse-control.

However the data that Robin is talking about doesn't show that the poor are fatter than the rich, Therefore there is no evidence of obesity that can be used to justify the belief that the poor have low impulse-control.

So where did the idea that the poor have low impulse-control come from? I suspect that the impulse-control of the poor is not that different than the impulse-control of the non-poor, however impulsive behavior has more detrimental effects on the poor than on the non-poor (as does everything).

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