Obesogens

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shpalman
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Obesogens

Post by shpalman » Mon Jun 06, 2022 8:59 am

Environmental toxins are worsening obesity pandemic, say not-mainstream scientists
Chemical pollution in the environment is supersizing the global obesity epidemic, according to a major scientific review.

The idea that the toxins called “obesogens” can affect how the body controls weight is not yet part of mainstream medicine. But the dozens of scientists behind the review argue that the evidence is now so strong that it should be. “This is critical because the current clinical management of obese patients is woefully inadequate,” they said.
The reviews are
https://www.sciencedirect.com/science/a ... 522200106X
https://www.sciencedirect.com/science/a ... 5222001095
https://www.sciencedirect.com/science/a ... 5222001083

I looked at the one about the chemicals to see if there was anything tracking the increase in levels in the environment, to at least correlate it with the increase in obesity (not that such a correlation would necessarily tell us anything) but there doesn't seem to be anything like that. Instead it seems to be a list of chemicals which they reckon are obesogenic, and then a list of chemicals which they seem to be hoping will turn out to be obesogenic, like glyphosate.
“The focus of the clinical people is on calories – if you eat more calories, you’re going to be more fat,” says Dr Jerrold Heindel, lead author of one of the three review papers, and formerly at the US National Institute of Environmental Health Sciences. “So they wait untill you get obese, then they’ll look at giving you diets, drugs, or surgery.

“If that really worked, we should see a decline in the rates of obesity,” he said. “But we don’t – obesity continues to rise, especially in children. The real question is, why do people eat more? The obesogenic paradigm focuses on that and provides data that indicate that these chemicals are what can do that.”

Furthermore, the scientists say, the approach offers the potential to prevent obesity by avoiding exposure to pollutants, especially in pregnant women and babies: “Prevention saves lives, while costing far less than any [treatment].”
What pollutants?
... these chemicals are everywhere: in water and dust, food packaging, personal hygiene products and household cleaners, furniture and electronics.
So, we need to avoid... everything?
The review identifies about 50 chemicals as having good evidence of obesogenic effects, from experiments on human cells and animals, and epidemiological studies of people. These include BPA and phthalates, also a plastic additive...

Other obesogens are pesticides, including DDT and tributyltin, former flame retardants and their newer replacements, dioxins and PCBs, and air pollution. Several recent studies link exposure to dirty air early in life to obesity.

The review also names PFAS compounds – so-called “forever chemicals” due to their longevity in the environment – as obesogens. These are found in food packaging, cookware, and furniture, including some child car seats.
So... buy fewer packets of food, don't cook, and don't eat furniture?
The obesogen paradigm has not been taken up by mainstream researchers so far. But Prof Barbara Corkey, at Boston University School of Medicine and past president of the Obesity Society, said: “The initial worldview was that obesity is caused by eating too much and exercising too little. And this is nonsense.”
She obviously hadn't listened to the question properly but rants about "eat less and move more" by reflex, rather than getting the memo that these chemicals supposedly make the "eat less and move more" harder.
Prof Robert Lustig at the University of California, San Francisco, and lead author of one of the reviews, said: “Gluttony and sloth are just the outward manifestations of these biochemical perturbations that are going on beneath the surface.”
Lustig said, “If I had to guess, based on all the work and reading I’ve done, I would say obesogens will account for about 15% to 20% of the obesity epidemic. But that’s a lot.” The rest he attributes to processed food diets, which themselves contain some obesogens.

“Fructose is a primary driver of a lot of this,” he said. “It partitions energy to fat in the liver and is a prime obesogen. Fructose would cause obesity even if it didn’t have calories.” A small 2021 trial found that an ultra-processed diet caused more weight gain than an unprocessed diet, despite containing the same calories in the meals offered to participants.

(* - This article was amended on 20 May 2022. An earlier version referred to a small 2021 trial that found an ultra-processed diet caused more weight gain than an unprocessed diet, and said that both diets contained the same calories. To clarify: the meals offered for both diets contained the same calories, but participants could choose how much of each meal they consumed.)
Seems like fructose was sold as being a "natural" sugar like the one in fruit, when in the American market it was just a cheap source of sugar from maize.

Back in 2018, the Guardian wrote the truth about obesogens...

I'm all for removing harmful things from food and the environment, but not for "oh no chemicals!"

Most of us now live in this obesogenic environment and there's little we can do about our "early years of child development" or our personal "transgenerational epigenetic obesity".

The fact that people are getting more overweight is complicated.
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Al Capone Junior
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Re: Obesogens

Post by Al Capone Junior » Sun Jun 19, 2022 2:54 pm

I'm betting on fructose as being a major player in the obesity epidemic. Dr Robert Lustig is pretty convincing.

But while I have some coursework which allows me to understand the science on this topic pretty well, I am not a researcher, and have not spent years of my life studying obesity.

So it will not surprise me if something else turns out to be the major causative factor in the obesity problem.

The notion of obeseogens seems at least plausible, but I can understand there being lots of skepticism at this point. Just as there seems to be plenty of skepticism about fructose's link to obesity

But then science is always skeptical of new ideas, by design. So let's see if the evidence supports this or that hypothesis, or a different one

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Re: Obesogens

Post by shpalman » Tue Oct 11, 2022 12:31 pm

Fat chance of escaping obesogens in Nature Physics of all places uncritically summarizes those three articles.

Buchanan, M. Fat chance of escaping obesogens. Nat. Phys. 18, 1136 (2022). https://doi.org/10.1038/s41567-022-01786-7
The most common view of the cause is a modern imbalance in diets, with many people taking in and storing more calories through eating than they spend through metabolism and exercise. In one sense — from the perspective of fundamental energy accounting — this must be true. Yet this ‘personal failing’ view of obesity is also profoundly misleading, because it’s just not true, empirically, that people today are eating more calories and burning less in exercise than people did decades ago [except it obviously is, like you just said]. In the US, for example, studies find that people have largely followed the medically recommended diets over the past 50 years (see Evan Cohen et al.,Nutrition 5, 727–232; 2015).
That's self-reported though isn't it?
The epigenetic mechanisms of some obesogenic effects are of particular relevance to the obesity epidemic because they imply the possibility that obesity often has origins in utero, as organisms inherit epigenetic influences that trigger life-long behaviours, such as a predilection to seek out foods high in sugar or fat, or overconsuming food calories even after no longer hungry. This indicates that the cause of obesity can sometimes look like an issue of simply eating too many calories, when it is actually a problem of deep-seated chemical metabolic disruption [which leads people to eat too many calories].
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Re: Obesogens

Post by IvanV » Tue Oct 11, 2022 3:56 pm

If I might stick my ignorant nose in here. I have had the following thoughts for a long time, and not encountered anyone who can help me refine out what might be rubbish, and what might be possible.

I start from the observation that sometimes people need to have their gut flora repopulating, via a "fecal transplant." (I've often wondered how it is delivered, I'm guessing in a soluble capsule you swallow whole.) There seems to be some evidence that if you give them gut flora from an obese person, the recipient then puts on a lot of weight. So a change in gut flora can make the same person more or less fat, other things being equal. I have heard it suggested that perhaps fecal transplants should be made more widely available to give people more beneficial flora.

What is driving this? Are the gut flora changing the efficiency of the breakdown of the food, so that you discard different amounts of potential calorie intake out your rear end? Are they changing your metabolism so you burn hotter, emit more heat and keep yourself warmer for example, and need a larger energy intake to achieve daily life? Or are they changing your craving for food so you eat more? Or are they changing your activity levels, for example by making you feel more tired?

Energy accounting is mentioned. My understanding is that there is quite a wide band of caloric consumption that does not tend to change your weight for a given level of activity. You have to consume beyond that stable band to put weight on. This is part of why it is hard to lose weight by dieting. If you eat a bit less than you were eating to put weight on, that will just put you back in the stable weight band.

So energy accounting is not as absolute. One calorie of excess consumption does not make you 1g fatter (seems to be the approx exchange rate.) The body can stabilise its weight within some fairly broad band of food consumption. So there is some process for using up excess calories, either by burning them to warm you up, or excreting them unused, in some range, before you start putting on weight. Similarly this tends to mean that you have to eat an awful lot less than you ate when you put on weight if you want to lose it by dieting. Part of why dieting is so difficult, I guess.

These ideas seem to present a number of possible mechanisms obesogens, as well as various gut flora, might have. We have mentioned the possibility that the make you hungrier, or less active. But they could also make your food processing more efficient, or change your metabolism. And perhaps the obesogens might achieve that by operating on the gut flora.

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Re: Obesogens

Post by IvanV » Tue Oct 11, 2022 5:59 pm

My mistake, the exchange rate is about 10 calories per 1g of fat.

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Re: Obesogens

Post by Millennie Al » Tue Oct 11, 2022 10:39 pm

IvanV wrote:
Tue Oct 11, 2022 3:56 pm
Are the gut flora changing the efficiency of the breakdown of the food, so that you discard different amounts of potential calorie intake out your rear end? Are they changing your metabolism so you burn hotter, emit more heat and keep yourself warmer for example, and need a larger energy intake to achieve daily life? Or are they changing your craving for food so you eat more? Or are they changing your activity levels, for example by making you feel more tired?
Possibly multiple effects. You might be interested in these:

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Re: Obesogens

Post by shpalman » Wed Nov 09, 2022 11:50 am

Meanwhile it seems there's a drug which causes weight loss by causing you to absorb less microplastic making food "repulsive".
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Re: Obesogens

Post by RoMo » Thu Nov 10, 2022 7:16 am

shpalman wrote:
Wed Nov 09, 2022 11:50 am
Meanwhile it seems there's a drug which causes weight loss by causing you to absorb less microplastic making food "repulsive".
I'm on semaglutide for diabetes and haven't found it's made food repulsive (I know it's a higher dose for weight management). When I first started it I had all of the GI side-effects listed so nausea meant I didn't want to eat much but now it just makes me feel full a lot of the time. Blood sugar is back under control and binge-eating issues have disappeared, so yay for Ozempic.

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Re: Obesogens

Post by shpalman » Sun Dec 04, 2022 12:04 pm

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Re: Obesogens

Post by shpalman » Sun Dec 04, 2022 12:06 pm

RoMo wrote:
Thu Nov 10, 2022 7:16 am
shpalman wrote:
Wed Nov 09, 2022 11:50 am
Meanwhile it seems there's a drug which causes weight loss by causing you to absorb less microplastic making food "repulsive".
I'm on semaglutide for diabetes and haven't found it's made food repulsive (I know it's a higher dose for weight management). When I first started it I had all of the GI side-effects listed so nausea meant I didn't want to eat much but now it just makes me feel full a lot of the time. Blood sugar is back under control and binge-eating issues have disappeared, so yay for Ozempic.
It would indeed seem that this is what semaglutide is actually for, and that it works for that, and I'm glad it's working for you.
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