It has been shown that the poor are more likely to be obese. This is only true in first-world countries, though. In third-world countries, the reverse occurs.
It has been widely presumed that this modern phenomenon is because poor people are doing something wrong — eating too much, eating the wrong things or being lazy. Those sins do not pertain to obesity in the first place, and we have said in several prior fat science columns that this point of view also is wrong about poor people.
An analysis of this question was recently reported in the January 2018 British Medical Journal(1) and brought to my attention by the perspicacious folks at ConscienHealth(2).
So the question these authors wanted to answer is, which comes first, poverty or obesity? Does poverty cause obesity or does obesity cause poverty? From the point of view of trying to explain obesity, if obesity causes poverty, then that is reverse causality.
The answer they found using data from 21 acceptable studies, 14 studies of poverty as a cause of obesity and 7 studies of obesity as a cause of poverty, is that obesity causes poverty and not the other way around. There was some influence of poverty as a cause of obesity in some of those studies, but that disappeared when publication bias was taken into account. Publication bias is the bias that studies that show no effects are often just never published. The evidence that obesity caused poverty was robust after publication bias was taken into account. Also it would seem that the prevailing bias is that poverty causes obesity since twice as many studies examining that point of view were found.
All of these studies were conducted with populations from the U.S., Canada and the UK. If we examined this issue in third-world countries, it’s hard to say what we would find. Are fatter people more employable in third-world countries because they are felt to be better people?
So we should stop trying to figure out what poor people are doing wrong, and try to combat stigmatization of and discrimination against people with obesity. There probably are some jobs that obese people can’t do, like crawling into tight tunnels. On the other hand, we would make a dent in the war against poverty by not handicapping smart, well-prepared people with obesity.
1. Kim TJ, Knesebeck OVD Income and obesity: what is the direction of the relationship? A systematic review and meta-analysis http://dx.doi.org/10.1136/bmjopen-2017-019862
John DiTraglia, M.D., is a pediatrician in Portsmouth. He can be reached by email at firstname.lastname@example.org or call 740-354-6605.