obesity rates



The world has gotten fatter. Why?

It's definitely related to chemicals. People with the same diets have gotten fatter. People with the same jobs have gotten fatter. Laboratory animals have gotten fatter.

Whatever happened started around 1970 in America.



So, what chemicals?

You can look at correlations, and this is useful information, but everything is correlated with everything else. It's very easy to find these correlational studies, which is why you should search for them yourself to make sure they're not being cherry-picked by an article's author.

For example, people at higher altitude have lower obesity rates. Now, is this due to population differences? Less oxygen? Or is it because water flows downhill, and people at lower altitudes have water that accumulated more contaminants? Studies disagree!

There are so many variables and cross-correlations that it's impossible to distinguish correlation from causation without some understanding of the mechanisms. The human proteome is far from understood, so you just have to have a general understanding of the kinds of proteins in cells, the kinds of things they bind to, and what molecules could bind to them in problematic ways or be metabolized into something harmful. Fortunately (?) I'm probably in the top 100 people worldwide when it comes to the relevant molecular toxicology; I wrote this 6 years ago and my understanding has gotten better since then. And I'm here to tell you, it's past time to start banning some stuff.



For obesity in particular, there's a good correlation between soda consumption and obesity. Drinks would not be carbonated if it wasn't somehow important. Normally people stop eating sugary things instead of having too much sugar at once. Carbonation interferes with that; my basis for saying this is drinking some soda and thinking about it. That may happen because prehistorical humans needed to eat fermenting fruits before they became inedible, but really the reason doesn't matter.

So, if you're trying to lose weight, maybe start by not drinking soda. Don't drink diet soda with artificial sweeteners either: that messes with your insulin regulation and you can get diabetes. If this is too much for somebody to do, then I guess they don't really care that much.



Now then, on to those chemicals. There's a fairly standard list of concerning chemicals that many scientists have been metaphorically shouting about as loud as they can:

- trans fats
- bisphenols
- phthalates
- fluorosurfactants
- brominated diphenyl ethers


There are also some other problems that are probably caused by synthetic chemicals that recently became widespread, including:

- declining testosterone levels in men
- earlier puberty in girls


Which problems are caused by which chemicals? Here's a better question: does it matter? They're all bad, ban them all and see what happens.

It's very easy to replace trans fats with precipitated palm oil solids. But companies took decades to do that. They lobbied against requirements, and only went ahead when governments started banning trans fats anyway. Corporate leadership hates changing their working formula, even if it's easy.

When Americans started being concerned about bisphenol A in polycarbonate, the FDA assured people it's actually safe, and eventually then banned it in certain products while still saying it's actually probably safe - not because of anything related to science, just due to public pressure. Receipts still have lots of BPA in them, except for the BPA-free ones - which use BPS instead which is just as bad. If you work a retail job and handle a lot of receipts, maybe you want to wear gloves.

Even when the EPA bans something, it's a narrow ban that deliberately excludes other bad stuff that companies say they want to use instead. The EPA started restricting PFOA and PFOS usage and DuPont just started selling slightly different fluorosurfactants. The correct thing was a more categorical ban, but the EPA wasn't going to do that because it would've annoyed DuPont and top EPA people want to get jobs there later.

Anyway, the FDA and EPA generally won't ban stuff unless it's not used yet or there's massive public pressure. At this point I don't even care about the scientific validity of the articles that create that pressure; go write some posts about how fluorosurfactants disrupt natural leylines and crystal formations if that's what people are into.



I'm sure lobbyists for chemical companies would whine about all the important applications of these chemicals, so let's look at some.


Fluorosurfactants are used to increase the stain resistance of things like carpets and pants. This application is a net negative. Ban it! Ban all deliberate inclusion of fluorosurfactants in consumer products!

They're used in some firefighting foams. This is completely unnecessary for fighting forest fires. Ban it! For extinguishing oil spills in eg airports, AFFF is quite effective. It's possible to replace fluorinated AFFF with hyperbranched hydrocarbon surfactants; this is a worthwhile research project.

They're used for emulsion polymerization of teflon. This is the hardest application to replace, and whether or not it's worthwhile depends on what you're doing with it.

Teflon coatings for cooking appliances are a net negative. Ban it!

Teflon tape is pretty useful for plumbing, and the amount used is pretty small. Allow it!

If you convert perfluoro fatty acids to ethoxylated perfluoro fatty alcohols, those are much less hazardous. However, they eventually biodegrade to perfluoro fatty acids, so this doesn't solve the environmental problem, it just mitigates direct exposure from consumer products.

Logically, branched fluorosurfactants might be less problematic. So, I did a google search for that and found Tivida which is supposedly less bad. If you need fluorosurfactants for AFFF or emulsion polymerization, I guess those branched ones are likely to be somewhat better environmentally. Maybe governments should even buy out their patents on that.

hydrogenated vegetable oil

Ban it! There are already alternatives in place for every application so further discussion is a waste of time.


Polycarbonate drink bottles? Unnecessary and bad for you. Ban it! Polycarbonate is sometimes useful but there's absolutely no need to use it in food containers. They're also getting replaced by PET copolymers in many applications; their advantage over PET was often just greater transparency.

Bisphenols are used in thermal paper for receipts. They're just weak acids with a certain melting point range and low volatility. If you banned them companies would figure something out, but they won't unless bisphenols are banned. Also, inkjet printers are cheap enough for receipts if the ink isn't overpriced; tank inkjets are cheap enough per page that receipt-sized ones would be cheap enough for receipts printing.


Probably my most radical position here: I think every application of PVC has alternatives that are better overall, and PVC usage should be categorically banned.

fire retardants

PBDEs are probably the most-discussed hazardous additive, but there are other hazardous ones too. A complete list would be long.

They're often added to polyurethane foam, largely because of regulations in California that existed because of concerns about cigarattes starting fires. If you need soft and flexible polyurethane you want to use polyethers which are flammable, but for most polyurethane foam applications it should work to instead use polycaprolactone or even isophthalate polyester polyols which are less flammable. Or you could use a different foam, maybe ionomer foam. Then you can add mineral particles instead of organic fire retardants, maybe precipitated calcium carbonate. Ban it!

Lots of PBDEs are added to plastics in aircraft because the FAA has extreme requirements regarding flammability of stuff in aircraft. There are other plastics that can be used instead; those are just more expensive than adding lots of PBDEs. Ban it!



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