3 ms·

This might have been covered in some part I skimmed over, but they never seemed to offer a mechanism for contaminated water in a drainage basin entering the loc

This might have been covered in some part I skimmed over, but they never seemed to offer a mechanism for contaminated water in a drainage basin entering the local food supply via processed foods in a way that wouldn’t also impact a plant-based (e.g. potato-only) diet. Did anyone get any insight there or is that really a gap in their explanation? As an aside, I have an unfortunate and deep association between Microsoft Word-typesetting and graphs with papers I wrote in high school that put me in a skeptical stance from the start

joe_the_user 5y ago
The thing about the article is it's not really offering any air tight explanations. It looks at a significant amount of data and asks what's correlated and what isn't - many common explanations simply don't fit the data at all. So it comes down to contaminants and psychological effects. But it is not making any definitive pronouncements about which contaminants or how.
jeffbee 5y ago
What makes you suspect this was typeset in Word?
jaggederest 5y ago
You have to segment the claims in two: Claim one (We have eliminated mechanisms aside from contamination for the obesity epidemic) rests essentially on anthropological studies with "uncontaminated" populations and conversely on the fact that animals in close contact with humans are also becoming obese rapidly even when holding calories constant (e.g. lab rats) Claim two posits some substances that might be responsible, and I think roughly is oriented around: a) antibiotics are intensively used in animal cultivation in a way that might leak into the food supply and water table downstream. b) PFAS accumulate biologically after exposure at parts-per-billion levels, and become increasingly more concentrated as you go up the food chain and downstream, but e.g. potatoes are not exposed to enough PFAS to hit the thresholds for deleterious effects. c) I don't think that lithium is actively taken up by plants to the degree that would affect pure unprocessed plant consumption, it's mostly about direct exposure and water contamination downstream. I think the claim one hypothesis is really strong. I've had a similar hypothesis for a few years now, though mine was more oriented around infection than contagion, but similar in terms of structure - the more people you put close together the more likely they are to cross-contaminate with some substance that makes them obese, and the clearer difference we have between baseline humanity ~100y ago and modern ones suffering from the obesity epidemic. I think the claim two hypothesis is a little bit weaker, but it's interesting that they have 3 proposed mechanisms that range from known effect, known presence (antibiotics), known presence but unknown effect (PFAS), and unknown presence but known effect (lithium), so I think they roughly descend in order of likelihood of explaining the obesity epidemic. I would guess, obviously, the answer is "all three", based just on the severity of the epidemic, but I'd guess it's quite likely antibiotics have a small effect, and also somewhat likely PFAS have a large effect, while I think the lithium hypothesis is the weakest of the three, but would be interesting to analyze further.
kilotaras 5y ago
> This might have been covered in some part I skimmed over, but they never seemed to offer a mechanism for contaminated water in a drainage basin entering the local food supply via processed foods in a way that wouldn’t also impact a plant-based (e.g. potato-only) diet. The higher the food chain you go - the higher amount of contaminants deposited. One of the most famous examples of this is mercury levels is higher in large fish as the food chain is longer.
frompdx 5y ago
One point that the paper does cover is what states in the United States have the greatest rates of obesity. These states are those situated between the Rocky Mountains and Appalachian mountains. Particularly those along the Mississippi river (page 20). The states that produce the most potatoes are on the other side of the Rocky Mountains, separated from the Mississippi, and have lower obesity rates. I did not see that this was made explicit in the paper though.

joe_the_user 5y ago

The thing about the article is it's not really offering any air tight explanations. It looks at a significant amount of data and asks what's correlated and what isn't - many common explanations simply don't fit the data at all. So it comes down to contaminants and psychological effects. But it is not making any definitive pronouncements about which contaminants or how.

jeffbee 5y ago

What makes you suspect this was typeset in Word?

jaggederest 5y ago

You have to segment the claims in two: Claim one (We have eliminated mechanisms aside from contamination for the obesity epidemic) rests essentially on anthropological studies with "uncontaminated" populations and conversely on the fact that animals in close contact with humans are also becoming obese rapidly even when holding calories constant (e.g. lab rats) Claim two posits some substances that might be responsible, and I think roughly is oriented around: a) antibiotics are intensively used in animal cultivation in a way that might leak into the food supply and water table downstream. b) PFAS accumulate biologically after exposure at parts-per-billion levels, and become increasingly more concentrated as you go up the food chain and downstream, but e.g. potatoes are not exposed to enough PFAS to hit the thresholds for deleterious effects. c) I don't think that lithium is actively taken up by plants to the degree that would affect pure unprocessed plant consumption, it's mostly about direct exposure and water contamination downstream. I think the claim one hypothesis is really strong. I've had a similar hypothesis for a few years now, though mine was more oriented around infection than contagion, but similar in terms of structure - the more people you put close together the more likely they are to cross-contaminate with some substance that makes them obese, and the clearer difference we have between baseline humanity ~100y ago and modern ones suffering from the obesity epidemic. I think the claim two hypothesis is a little bit weaker, but it's interesting that they have 3 proposed mechanisms that range from known effect, known presence (antibiotics), known presence but unknown effect (PFAS), and unknown presence but known effect (lithium), so I think they roughly descend in order of likelihood of explaining the obesity epidemic. I would guess, obviously, the answer is "all three", based just on the severity of the epidemic, but I'd guess it's quite likely antibiotics have a small effect, and also somewhat likely PFAS have a large effect, while I think the lithium hypothesis is the weakest of the three, but would be interesting to analyze further.

kilotaras 5y ago

> This might have been covered in some part I skimmed over, but they never seemed to offer a mechanism for contaminated water in a drainage basin entering the local food supply via processed foods in a way that wouldn’t also impact a plant-based (e.g. potato-only) diet. The higher the food chain you go - the higher amount of contaminants deposited. One of the most famous examples of this is mercury levels is higher in large fish as the food chain is longer.

frompdx 5y ago

One point that the paper does cover is what states in the United States have the greatest rates of obesity. These states are those situated between the Rocky Mountains and Appalachian mountains. Particularly those along the Mississippi river (page 20). The states that produce the most potatoes are on the other side of the Rocky Mountains, separated from the Mississippi, and have lower obesity rates. I did not see that this was made explicit in the paper though.