9 ms·

Again. Missing big fat disclaimer. "Correlation does not imply causation". It is wrong to jump from "Weight loss relapse associated with exposure to perfluoroal

Again. Missing big fat disclaimer. "Correlation does not imply causation". It is wrong to jump from "Weight loss relapse associated with exposure to perfluoroalkylate substances" to "Obesogenic PFASs may cause weight gain and thus contribute to the obesity pandemic". Here, the word "may" is correct but it should really be "we just don't know, it is possible". But "obesogenic" suggest that the link has been proven which it has not. I am not defending PFAS. But our history is full of missed opportunities and billions of people doing stupid shit for decades because somebody jumped to conclusions to fast. We have still not eradicated notion that fats are all wrong and need to be removed from the diet where it is exactly the opposite -- it is very likely that removal of fats from the diet is responsible for the large part of obesity epidemic. Right after people believing you need to eat multiple meals a day to be healthy. It is important to keep focus on stuff that we already know is detrimental to our health and these are excessive amounts of carbohydrates (filling the void when fats were removed from the diet), refined sugars and reduced time between meals not allowing people to exercise their lipid transport in reverse.

CoastalCoder 3y ago
> Again. Missing big fat disclaimer. "Correlation does not imply causation". It is wrong to jump from "Weight loss relapse associated with exposure to perfluoroalkylate substances" to "Obesogenic PFASs may cause weight gain and thus contribute to the obesity pandemic". That's correct, but it's interesting to ask: what should public policy be in light of these findings?
- gcheong 3y ago
  The findings of this one study should be rigorously evaluated and replicated first, not that much of our public policy is based on any kind of evidence but that would be the right way to go about it.
- marcosdumay 3y ago
  You mean, it's correct that the facts are not actionable, but what should we do?
- twawaaay 3y ago
  None? There is nothing actionable here. We already know PFAS are dangerous for other reasons and the war against them is warming up. And policy is not/should not be made based on just one study. Sadly, there are too many contradicting studies. Things like this need to be re-checked so that policymakers and societies don't waste time chasing things that don't bring any results. Even then, we need to understand what is magnitude of this effect, what level of PFAS translate to what increase in obesity risk, etc. Then put it in context of already planned PFAS reductions. Then if I was policymaker I would also look at what are potential projects we are not working on and where are highest return on investments. Just because there is something you can fix doesn't mean you should fix it. There might be another thing with more ROI where you should be spending your efforts. That is assuming the conclusions of this study are correct, which I don't believe they are.
now__what 3y ago
> reduced time between meals not allowing people to exercise their lipid transport in reverse. I hadn't heard of this before, but it's interesting; despite receiving guidance to consume smaller, more frequent meals, I've found the practice has a negative effect on my own energy levels and weight stability. Would you mind elaborating on this point, or providing links to further reading?
- twawaaay 3y ago
  It is called fasting. It has been practiced for entirety of human history in all societies except for last couple of decades. Fasting is an opportunity for the body to burn stored fats. Insulin is a hormone that tells every cell in the body to take sugars from the bloodstream and effectively prevents burning stored fats. When cells are used to burning sugars all the time, when given access to sugars and fats they will chose sugars preferentially. So as long as they have supply of sugar there is very little fat burning happening. What's more, when you stop eating for a moment, for whatever reason, your body still does not have ability to burn much fat for energy because the metabolic pathways to do it are too dormant to provide enough energy on a moments notice. You become hungry which is your body telling you it can't get energy and you resolve the only way to fix the issue is by putting more carbohydrate-rich food in your mouth. Fasting periods are necessary for the body to train those metabolic pathways. For example, by eliminating breakfast and not snacking in the evening you can easily double the time it takes between two meals giving couple of hours each day during which your body has to get energy from the fats. Over time your body relearns to burn fats and when you don't eat for a moment for whatever reason it is able to start burning fats faster and start providing more energy lessening the feeling of hunger and immediate need to put more food in your mouth. Fasting is the normal state of the human body. We have evolved in conditions where food was relatively scarce and when we finally caught something, we had to eat it here and now and then move on and wait until we are able to catch something else at unknown future time. This means we have evolved to accept food for a relatively short portion of time, be very good at storing energy as fat and then to use this fat for a long time until we could catch something else.
  - now__what 3y ago
legulere 3y ago
History is full of huge disasters where absence of proof of negative effects was seen as proof of absence of negative effects. PFAS are such an example. There are already proven negative effects, many correlations are probable causations because we have good explanations like endocrine disruption for them, and worst of all bioaccumulation means that we cannot turn the clock backwards and all the more reason to use the precautionary principle. All chemicals should be considered dangerous without any other knowledge. Coevolution of humans with chemicals (which has a big overlap with “natural” in contrast to synthetic chemicals) is just a prior that makes danger less likely.
- deleted 3y ago
  [deleted]
- tracker1 3y ago
  Yeah... I'd love to see a "reset" to foods that were generally available 150 years ago. Before industrialized foods were broadly available. Meat, Eggs, common veg, and pre-gmo grains and legumes. And kind of start over. I understand modern farming allows the world as it is to be fed... but there's plenty of room for states/countries that are able to financially to try to do much better.
scythe 3y ago
>Correlation does not imply causation Correlation does not guarantee causation. But the stronger the correlation, the more you suspect that two phenomena are causally linked somehow. In this case, three pounds over half a year is a surprisingly large effect. If it were to continue, even if it slowly approaches an equilibrium, it could be responsible for a substantial increase in total body weight in millions of people. It's very possible that PFAS is just acting as a proxy for exposure to packaged foods, but that would be interesting in itself. In this case, the best course of action is to study the phenomenon more closely, mostly because it is large.
- twawaaay 3y ago
  Causal link requires an investigation to understand what is the nature of the link. Is it possible that people who are likely to be more obese are also likely to eat garbage food delivered in low quality plastic packaging? And more healthy people are more likely to cook their food from higher quality ingredients like fresh produce that is not delivered in plastic? See, the above explanation, I think very reasonable (though requiring a proof), could explain why obese people could have higher PFAS? Another possible explanation (again, I am just sayin', no proof for it): imagine all food is contaminated with PFAS, but obese people have different chemistry that is worse at removing PFAS from their bodies. This is why we say "correlation does not imply causation". Yes, highly correlated things are interesting and require further investigation. Even if PFAS is not causing obesity we still might learn something interesting about either PFAS or obesity or something else that is connected to both.
tracker1 3y ago
Of course the switch off to the likes of margarine, seed oils and other high omega-6/3 ratio fats doesn't help. Was just looking up the cost of Beef tallow, say if someone did want to try to convince a restaurant to switch back and it's now 5x the cost of the "vegetable" seed based oils. It may last longer in a commercial setting, but that's a hard pill.
- twawaaay 3y ago
  You are right. Just because food is fatty doesn't mean it is healthy. I did not want to make the comment too long but there is the concern for the quality of fats which is pretty complicated problem. There are some simple rules -- for example you definitely want to stay away from highly processed fats. But further than that things get more complicated. As an example, we are told that fish is generally one of the healthiest fats around. But what people forget is that this is assuming wild fish and the kind that does not accumulate rare metals. Salmon is pretty health... unless we are talking farmed salmon. Farmed salmon is fed with highly processed, carbohydrate-rich feed which completely changes the fat content of the salmon making it very high omega 6 to 3 ratio. And God knows what else... Beef tallow -- I have simple solution for this at least for my home use. I buy lots of quality red meat. Whenever I may broth or render fats for any reason, I gather them all and store them for later.
  - tracker1 3y ago
    That's cool.. honestly, when I've made beef broth myself, it never really tastes that good. But I will do a filter through a fine mesh chinoise, and take the fat out as it settles to cook with. I do try to keep about half my meat/egg intake "clean" (pasture raised, etc) but it can be cost prohibitive sometimes.
    - twawaaay 3y ago
      I can make good tasting beef broth but I usually don't even bother. I make a huge, 15L pot of broth. I use various pieces of meat, especially ones that have a lot of collagen. If I think I have too little cartilage I will add achilles tendons which are pretty much pure collagen. I brown everything them either on a pan or in the oven and I simmer it for at least 12h until all meat disintegrates and all collagen and fats dissolve. I then remove and discard meat and bones and small particles by filtering it through fine mesh strainer, I remove (and store) the tallow. And then I reduce everything about four-five times to get the meatiest substance on Earth. Cool it down, it should completely congeal in room temperature. I cut it into cubes, throw it into plastic bags and into the freezer. Then whenever I want to make soup or a sauce or risotto or whatever else, I just take some cubes from the freezer and drop directly into the pan or pot. I also make and freeze other useful things. For example, I always keep a supply of bolognese sauce which I make 9L at a time and then lasts me for a year.

CoastalCoder 3y ago

> Again. Missing big fat disclaimer. "Correlation does not imply causation". It is wrong to jump from "Weight loss relapse associated with exposure to perfluoroalkylate substances" to "Obesogenic PFASs may cause weight gain and thus contribute to the obesity pandemic". That's correct, but it's interesting to ask: what should public policy be in light of these findings?

gcheong 3y ago
The findings of this one study should be rigorously evaluated and replicated first, not that much of our public policy is based on any kind of evidence but that would be the right way to go about it.
marcosdumay 3y ago
You mean, it's correct that the facts are not actionable, but what should we do?
twawaaay 3y ago
None? There is nothing actionable here. We already know PFAS are dangerous for other reasons and the war against them is warming up. And policy is not/should not be made based on just one study. Sadly, there are too many contradicting studies. Things like this need to be re-checked so that policymakers and societies don't waste time chasing things that don't bring any results. Even then, we need to understand what is magnitude of this effect, what level of PFAS translate to what increase in obesity risk, etc. Then put it in context of already planned PFAS reductions. Then if I was policymaker I would also look at what are potential projects we are not working on and where are highest return on investments. Just because there is something you can fix doesn't mean you should fix it. There might be another thing with more ROI where you should be spending your efforts. That is assuming the conclusions of this study are correct, which I don't believe they are.

now__what 3y ago

> reduced time between meals not allowing people to exercise their lipid transport in reverse. I hadn't heard of this before, but it's interesting; despite receiving guidance to consume smaller, more frequent meals, I've found the practice has a negative effect on my own energy levels and weight stability. Would you mind elaborating on this point, or providing links to further reading?

twawaaay 3y ago
It is called fasting. It has been practiced for entirety of human history in all societies except for last couple of decades. Fasting is an opportunity for the body to burn stored fats. Insulin is a hormone that tells every cell in the body to take sugars from the bloodstream and effectively prevents burning stored fats. When cells are used to burning sugars all the time, when given access to sugars and fats they will chose sugars preferentially. So as long as they have supply of sugar there is very little fat burning happening. What's more, when you stop eating for a moment, for whatever reason, your body still does not have ability to burn much fat for energy because the metabolic pathways to do it are too dormant to provide enough energy on a moments notice. You become hungry which is your body telling you it can't get energy and you resolve the only way to fix the issue is by putting more carbohydrate-rich food in your mouth. Fasting periods are necessary for the body to train those metabolic pathways. For example, by eliminating breakfast and not snacking in the evening you can easily double the time it takes between two meals giving couple of hours each day during which your body has to get energy from the fats. Over time your body relearns to burn fats and when you don't eat for a moment for whatever reason it is able to start burning fats faster and start providing more energy lessening the feeling of hunger and immediate need to put more food in your mouth. Fasting is the normal state of the human body. We have evolved in conditions where food was relatively scarce and when we finally caught something, we had to eat it here and now and then move on and wait until we are able to catch something else at unknown future time. This means we have evolved to accept food for a relatively short portion of time, be very good at storing energy as fat and then to use this fat for a long time until we could catch something else.
- now__what 3y ago

legulere 3y ago

History is full of huge disasters where absence of proof of negative effects was seen as proof of absence of negative effects. PFAS are such an example. There are already proven negative effects, many correlations are probable causations because we have good explanations like endocrine disruption for them, and worst of all bioaccumulation means that we cannot turn the clock backwards and all the more reason to use the precautionary principle. All chemicals should be considered dangerous without any other knowledge. Coevolution of humans with chemicals (which has a big overlap with “natural” in contrast to synthetic chemicals) is just a prior that makes danger less likely.

deleted 3y ago
[deleted]
tracker1 3y ago
Yeah... I'd love to see a "reset" to foods that were generally available 150 years ago. Before industrialized foods were broadly available. Meat, Eggs, common veg, and pre-gmo grains and legumes. And kind of start over. I understand modern farming allows the world as it is to be fed... but there's plenty of room for states/countries that are able to financially to try to do much better.

scythe 3y ago

>Correlation does not imply causation Correlation does not guarantee causation. But the stronger the correlation, the more you suspect that two phenomena are causally linked somehow. In this case, three pounds over half a year is a surprisingly large effect. If it were to continue, even if it slowly approaches an equilibrium, it could be responsible for a substantial increase in total body weight in millions of people. It's very possible that PFAS is just acting as a proxy for exposure to packaged foods, but that would be interesting in itself. In this case, the best course of action is to study the phenomenon more closely, mostly because it is large.

twawaaay 3y ago
Causal link requires an investigation to understand what is the nature of the link. Is it possible that people who are likely to be more obese are also likely to eat garbage food delivered in low quality plastic packaging? And more healthy people are more likely to cook their food from higher quality ingredients like fresh produce that is not delivered in plastic? See, the above explanation, I think very reasonable (though requiring a proof), could explain why obese people could have higher PFAS? Another possible explanation (again, I am just sayin', no proof for it): imagine all food is contaminated with PFAS, but obese people have different chemistry that is worse at removing PFAS from their bodies. This is why we say "correlation does not imply causation". Yes, highly correlated things are interesting and require further investigation. Even if PFAS is not causing obesity we still might learn something interesting about either PFAS or obesity or something else that is connected to both.

tracker1 3y ago

Of course the switch off to the likes of margarine, seed oils and other high omega-6/3 ratio fats doesn't help. Was just looking up the cost of Beef tallow, say if someone did want to try to convince a restaurant to switch back and it's now 5x the cost of the "vegetable" seed based oils. It may last longer in a commercial setting, but that's a hard pill.

twawaaay 3y ago
You are right. Just because food is fatty doesn't mean it is healthy. I did not want to make the comment too long but there is the concern for the quality of fats which is pretty complicated problem. There are some simple rules -- for example you definitely want to stay away from highly processed fats. But further than that things get more complicated. As an example, we are told that fish is generally one of the healthiest fats around. But what people forget is that this is assuming wild fish and the kind that does not accumulate rare metals. Salmon is pretty health... unless we are talking farmed salmon. Farmed salmon is fed with highly processed, carbohydrate-rich feed which completely changes the fat content of the salmon making it very high omega 6 to 3 ratio. And God knows what else... Beef tallow -- I have simple solution for this at least for my home use. I buy lots of quality red meat. Whenever I may broth or render fats for any reason, I gather them all and store them for later.
- tracker1 3y ago
  That's cool.. honestly, when I've made beef broth myself, it never really tastes that good. But I will do a filter through a fine mesh chinoise, and take the fat out as it settles to cook with. I do try to keep about half my meat/egg intake "clean" (pasture raised, etc) but it can be cost prohibitive sometimes.
  - twawaaay 3y ago
    I can make good tasting beef broth but I usually don't even bother. I make a huge, 15L pot of broth. I use various pieces of meat, especially ones that have a lot of collagen. If I think I have too little cartilage I will add achilles tendons which are pretty much pure collagen. I brown everything them either on a pan or in the oven and I simmer it for at least 12h until all meat disintegrates and all collagen and fats dissolve. I then remove and discard meat and bones and small particles by filtering it through fine mesh strainer, I remove (and store) the tallow. And then I reduce everything about four-five times to get the meatiest substance on Earth. Cool it down, it should completely congeal in room temperature. I cut it into cubes, throw it into plastic bags and into the freezer. Then whenever I want to make soup or a sauce or risotto or whatever else, I just take some cubes from the freezer and drop directly into the pan or pot. I also make and freeze other useful things. For example, I always keep a supply of bolognese sauce which I make 9L at a time and then lasts me for a year.