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Comment by tsimionescu

2 days ago

You'll find many people claiming almost the exact opposite, just as confidently. Plant fats are generally seen as much healthier, especially olive oil and similar fats. This idea that the combination of macronutrients that a food contains also seems highly suspect - generally people tend to think that macronutrients work independently of each other.

The reality is, of course, that we just don't know. Nutrition "science" is almost entirely bogus (the only real part of it is the discovery of the nature and functioning of the various vitamins, and thus the elimination of scurvy and similar diseases - plus a few other extremes). Even the existence and importance of dietary fiber in many foods was a very recent discovery (resistant starch and oligosaccharides were only identified as dietary fiber in the 2000s, for example) - meaning that even the base caloric contents of many foods were wrongly measured as late as the 2000s (and who knows what else we're missing here).

"generally people tend to think that macronutrients work independently of each other"

Well, that is obviously the wrong idea. Even basic logic speaks against it: people lose weight on keto diet, people lose weight on vegan diet... so neither protein, fat nor carbs can be causing obesity. But what do foods that we know are obesogenic have in common? 1) They are highly processed and/or 2) they combine fats and carbs into single package.

But it is true that we don't know for certain. What we do know is that this dietary experiment we have had going since 1970s at the latest has failed completely. As I tend to say: paleo diet should be the basis of any diet, and then you further adjust it based on how your body responds.

  • People lose weight, temporarily, on all sorts of diets, restricted or not. It is the nature of specific diets that they tend to reduce appetite, and simply following a diet tends to reduce snacking - by virtue of selection bias, mostly (that is, people who are successfully following a diet are by definition people who aren't overeating).

    Very traditional diets also tended to include lots of foods that are both highly processed and contain both sugars and fats, like cheese or sweet nut cakes. Paleo diets are a modern invention, and have little in common with the concept of what our ancestors ate. They often have deeply anachronistic ideas, like favoring raw foods, when the use of fire has been a core part of our ancestors consumption since way before Homo Sapiens existed.

    • I haven't found any paleo dieter that promotes eating solely or even primarily raw foods. That idea seems to be more common in carnivore and vegan communities.

      Traditional diets however are still diets that came after the advent of agriculture.

  • That is not correct.

    People lose fat on calorie restricted diet. How will you get to it, either by counting them or by improving metabolism or by changing insulin levels, is a different thing.

    Vegan or keto diet can both be calorie restricted, as much as any macronutrient mixture. However, it doesn't mean its sustainable. If you are hungry all the time, you can stay on the diet for some time, but not forever. Since insulin is the primary storage hormone, reducing it will make you less fat (just look at type 1 diabetics). We now know that carbs are the highest promoters of insulin, that fat has 0 influence, and protein some. We have drugs like metformin or GLP-1 that brute force some of it and they are working.

    So, we know that sugar is mostly bad and that fat and protein are not. Ofc, some fats are bad for other reasons (by promoting inflamation) but that has nothing to do with obesity.

    • Thing about the keto diet is that "hungry all the time" simply... doesn't happen. In fact, bigger problem for keto dieters tends to be being satiated all the time and consequently undereating.

      "Hungry all the time" is actually vegan thing, but plants have so few calories and pass through so quickly that vegans end up being skinny despite eating literally all the time.

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  • The big question with such foods is are they worse for you just in and of themselves, or do they tend to promote obesity through inducing people to eat more? For the most part, research seems to suggest that as far as weight gain is concerned, calorie is a calorie (whether from fat, carbs, or protein), but some foods seem to induce people to eat more in general, compared to others. (highly processed and high-sugar food seeming to be some of the worst in this regard, but it's not clear exactly what it is about highly processed food that promotes this).

    • From what I have gathered (through research and by using myself as a guinea pig), there are two things about highly processed food that promote overeating: 1) high carbohydrate content 2) lack of nutrients

      High carbohydrate content causes sugar spikes, which leads to insulin spikes, and insulin spikes both a) cause hunger and b) promote storage of energy in the form of body fat: https://pubmed.ncbi.nlm.nih.gov/3894001/

      Second issue is as I said lack of nutrients. Your body needs nutrients, and will force you to eat until nutritional requirements had been satisfied. Since processed foods have very few nutrients, your organism compensates by increasing dietary intake... which means increasing caloric intake.

  • I'm skeptical that paleo diet would be healthy for long term. There are studies where they find atherosclerosis in pre-industrial hunter-gatherer remains. It's called HORUS study.

    • From what I've managed to find in the newest research, it apppears that diet does not appear to have any impact on atherosclerosis itself. But, as they say, more data needed.

This. The amount of faith in nutrition "science" indicates severe science illiteracy in the public.

In general there are way too many confounds, and measurement is far too poor and unreliable (self-report that is wrong in quality and quantity; you can't track enough people for the amount of time where supposed effects would manifest), there is almost zero control over what people eat (diets and available foods even considerably over a decade for whole countries, never mind within individuals), and much of the things being measured lack even face/content validity in the first place (e.g. "fat" is not a valid category, and even "saturated vs. unsaturated" is a matter of degree, and each again with different kinds in each category).

We are missing so much of the basics of what are required for a real science here I think it is far more reasonable to view almost all long-term nutritional claims as pseudoscience, unless the effect is clear and massive (e.g. consumption of large amounts of alcohol, or extremely unique / restrictive diets that have strong effects, or the rare results of natural experiments / famines), or so extremely general that it catches a sort of primary factor (too much calories is generally harmful, regardless of the source of those calories).

Maybe it'll become actual science one day, but that won't be for decades.