The Estrogen Hypothesis of Obesity | Hacker News Reader

The Estrogen Hypothesis of Obesity

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Am I missing something? How does comparing GDP to obesity rates give any evidence that it is female hormones specifically that correlate with obesity? I'll admit I've only read the abstract and looked at the figures but I'm still lost how A gets to B here...

TFA observes that male obesity varies in response to GDP more than female obesity does. The thesis is that increasing exposure to "female" hormones with increasing GDP explains part of this phenomenon. I haven't read this carefully enough to judge that, however.

My field of study and my experience is not in medicine or public health, but GDP vs. obesity rates seems like poor evidence for this particular hypothesis. For example, one hypothesis I can think about that explains this is that in developing countries, it could be possible that women are often homemakers, and therefore, they don't have as much physical exercise as their male peers. In developed countries, where women are more free to work, the obesity rates are comparable...

I mean, I don't see a slam dunk "See, it's female hormones!" There could be a number of things from culture to lifestyle choices to work-life balance that can have affect on obesity that might correlate with GDP. They should have at least controlled against that, and I see no evidence of it.

The correlation itself is interesting, even without the female hormones.

>In developed countries, where women are more free to work, the obesity rates are comparable...

Or even: in developed countries, most work is not physical labor.

Being a homemaker in the developing world frequently involves a lot more physical activity than in the developed. Food and water are usually a lot less convenient, and may involve travel. Homemaking may also involve farming, and taking excess food from the garden to market which again, often involves travel.

Also, the physical effort involved in being in the workforce in the developed world can be almost nil. A lot of people have to stand up all day, or pick up boxes, but that's far from subsistence farming or hand-washing clothes.

Yeah, this study seems pretty shallow and fails to take into account other indirect factors which might influence obesity rates (so it's not necessarily A->B, but possibly A->B->C->...->Z).

Human culture and gender differences is overwhelmingly complex subject. This research is trying to establish direct relationship between estrogen and obesity, but hormones might have subtle but signficiant effects on human culture.

It is more likely a diet comprised of mostly carbohydrates and processed food along with low physical activity is the cause. But that is a title for another blog/article post on another day.

What would be some examples of "environmental estrogen-like substances associated with affluence?"

BPA: http://en.wikipedia.org/wiki/Bisphenol_A

Bisphenol A is in a lot of plastics (See: Polycarbonate), including soda drinks, and leeches into the drinks themselves in small amounts. BPA exhibits "Estrogenicity", in that it mimics the behavior of Estrogen in the body. Nearly everyone in developed countries has some level of BPA in them.

BPA has been linked to Obesity as well: http://en.wikipedia.org/wiki/Bisphenol_A#Obesity

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

Note that the BPA associated with soda is present in metal containers, as part of the plastic liner used to protect the can from the acidic soda. Those liners are in lots of other metal food containers.

Disposable plastic beverage bottles are almost all PETE, which doesn't contain BPA.

Quite a lot of plastics leach chemicals that can have estrogenic activity, according to this study http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ Take it with a grain of salt though.

Url changed from http://www.mdconnects.com/articles/1789/20140613/female-horm..., which points to this.

Thank you! I was just about to post how terrible that blogspam site was.

Didn't finish reading this, but was this data controlled for physical activity? In many developing countries, women are caretakers for the home and mostly stay home while men go outdoors for work, especially physical.

Yeah I am wondering this too. This has all the hallmarks of HAES / FA type logic. Activity levels and expected roles does have a lot to do with weight gain. Now perhaps there is some truth that estrogen may make it more difficult for women to keep off weight but its not the reason they are fat

Fatness in the this century is due to an abundance of processed food that is readily available and has simple storage needs. Combine that with an abundance of idle time, especially urban poor, and its not a good mix. I love going through photo archives and the one thing that stood out is the lack of obesity, its like the people taking photos went out of their way to not show it.

Welcome to the world of Wall-E. People are going to have to adapt, those selling packaged food will need to adapt, so that we don't end up there.

This is the widely accepted theory but it doesn't explain everything. For example, lab animals have actually gotten fatter over time as well, and they are eating carefully measured diets and living in controlled conditions.

Diets are also not effective at losing weight. People rarely stay on them, and a fat person must eat significantly fewer calories, not just the same amount, than a normal person to maintain a healthy weight. Their metabolisms resemble those of starving people, the body desperately trying to return itself to it's "normal" weight.

Likewise normal people fed lots of food to become fat, quickly return to their previous weight after they stop. Genetic studies find obesity is more heritable than nearly any other condition including mental illness, breast cancer, and heart disease. It also appears to be affected by epigenetics. If your grandmother was starving you have a higher probability of becoming obese.

The question thus turns to our modern Western society and why this process is not as coarsely observable, with the rates approaching parody [sic] as national gross domestic product increases.

Rogue spellchecker, typo, or Freudian slip?

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