4 ms·

sample size n=37 of which recruitment only happened in Shanghai without any real control for confounders, only evaluated over a period of two weeks with no long

by paimapi 2mo ago

sample size n=37 of which recruitment only happened in Shanghai without any real control for confounders, only evaluated over a period of two weeks with no longterm follow-ups, the dosage of 40g RS/d is very high (would take about 4-5 large potatoes daily for equivalency or ingesting likely expensive supplement), the crossover compares RS vs CS in the same participants with only a 4 week washout which is a weakness since fermentable fiber persists >4 weeks, also the supplement they used was industry-provided by a starch manufacturer which was weirdly not disclosed this is a great study if you are an overweight/obese adult without overt metabolic disease, willing and able to consume 90 g/d of starch supplement within a controlled diet, and living in Shanghai with similar baseline fiber intakes endemic to that population. it is extremely not generalizeable to you or even me though I fit more of those characteristics than I care to admit stay skeptical of small studies like this, friend

lluisantoni 2mo ago
Also, the authors claim the starch "inhibited lipid absorption." They do not argue why they used surrogate blood biomarkers instead of residual energy output in fecal samples (which is a better measurement). sample size is 37, number of authors 29
dudisubekti 2mo ago
> not generalizable But there's already a general advise on this: eat more fiber. https://med.stanford.edu/news/all-news/2017/08/hunter-gatherers-seasonal-gut-microbe-diversity-loss.html https://med.stanford.edu/news/all-news/2017/08/hunter-gather... We're a great ape, our body evolved to process a lot of fiber from fruits and starches. It's the modern fiber-deficient diet that's really weird. 90g/day of fiber is similar to the Hadza tribe diet, where they can consume 100-150g of fiber per day.
- iamacyborg 2mo ago
  Fiber’s the new fad supplement.
  - dudisubekti 2mo ago
    I hope you're not being serious, but they're not "supplements", they're food. You can easily get them from fruits and vegetables. While they're not essential in short-term survival, they're essential for long-term health: https://www.ncbi.nlm.nih.gov/books/NBK559033/ https://www.ncbi.nlm.nih.gov/books/NBK559033/ We have enough peer-reviewed studies on this.
  - arcanemachiner 2mo ago
    I thought we were onto protein now?
    - iamacyborg 2mo ago
      It’s on its way out, fiber’s the new thing.
    - adrian_b 2mo ago
      Eating enough protein is also important, especially for older people, to prevent the loss of muscular mass, but that does not change the fact that the food must also include enough "fiber". The US had for a long time a much too low recommendation of around 0.8 g of protein per kilogram of body weight per day. That has been discredited by various studies. It is an amount that is sufficient to keep you alive, but it is not sufficient to keep you in good health until an old age. It is not known with any certainty which is the optimum amount of protein intake. On certain lab animals protein restriction lengthens life, but for now there is no evidence that this also works for humans. Too much protein is known with certainty to be harmful for humans. I believe that it is likely that the optimum protein intake is somewhere between 1.2 and 1.5 grams of protein per day and per kilogram of body weight, for a person with no overweight. For an overweight person, the protein needs do not increase proportionally to the total mass, i.e. the extra fat does not need much protein. I wonder whether the so low protein recommendation of USA was actually intended for average Americans, which are likely to be overweight, in which case that number might provide an adequate protein intake.
  - PunchyHamster 2mo ago
    it has been for a while, a lot of foods advertise fiber
- amanaplanacanal 2mo ago
  We shouldn't assume that because we are a great ape that we eat the same as other great apes. Humans spent two million years away from the jungle evolving in the savanna, with very different food sources. Our guts changed quite a bit in that time, and our digestion doesn't work the same.
  - dudisubekti 2mo ago
    Good thing we're not just assuming, we're actually studying it too: https://www.ncbi.nlm.nih.gov/books/NBK559033/ https://www.ncbi.nlm.nih.gov/books/NBK559033/ Also savannah human diet is chock full of fiber too: baobab pulp, grass seeds, tuber plants, etc
    - adrian_b 2mo ago
      Their is no doubt that for millions of years the humans have eaten much less fiber than their ape ancestors. You just have to look to the belly of a healthy, non-obese human and compare it with the bellies of the apes. The bellies of the apes are much bigger, despite not having the fat of humans, because they have much longer intestines, which are packed in there, which are required for the fermentation of the large amount of fiber included in their diets. The intestines of humans are not so reduced as those of the obligate carnivores, but they are still much shorter than of most apes or monkeys. Our health is still dependent on eating a decent amount of "fiber", but the amount we need is not comparable with what an ape needs.
      - dudisubekti 2mo ago
        I mean yeah, of course. We don't need as much as fiber as gorilla. My point is just modern diet is severely lacking in fiber, when our gut evolved to process them. It's not a surprise this evolutionary mismatch will cause so many problems in our body.
        adrian_b 2mo ago
        I agree.
- paimapi 2mo ago
  a starch is not fiber and generally not broken down the same way in digestion afaik fiber is great and under-consumed (especially soluble) and is very well-studied on modern populations [0]. we don't really need to make mechanistic reasonings about evolutionary adaptations that occurred hundreds of thousands of years ago or rely on studies of a small, homogenized population whose lived realities are far from yours and mine plus, following the the hierarchy of evidence, mechanistic guesses are considered extremely low quality, only ranking above things like mouse studies [1] [0] https://www.uptodate.com/contents/healthy-diet-in-adults#H617032519 https://www.uptodate.com/contents/healthy-diet-in-adults#H61... [1] https://en.wikipedia.org/wiki/Hierarchy_of_evidence https://en.wikipedia.org/wiki/Hierarchy_of_evidence
  - adrian_b 2mo ago
    "Fiber" is a vague term that is used for the carbohydrates that cannot be digested by humans, so they reach the large intestine, where they are fermented by bacteria. This includes a part of the "resistant starch", which is poorly digested by humans, so a big part of it reaches the large intestine. So yes, the "resistant" starch counts as "fiber", but not all of it, because some part of it is hydrolyzed into glucose, which is absorbed.
    - paimapi 2mo ago
      this is bordering on pedantry but aren't there classifications by different regulatory and medical institutions of what fibers are and aren't? as far as I'm aware, a starch isn't a fiber unless a special exemption is carved out for it and only if that starch meets certain criteria for how it behaves looking into RS's in general, it seems like there is a special carve-out after a lot of industry lobbying for very specific forms of RS's to be classified as fibers and only if they have physiological effects similar to the classic definition of fiber: https://www.fda.gov/media/113663/download https://www.fda.gov/media/113663/download for practical reasons, I suppose I'm just not understanding why you don't eat more 'classical' fibers. psyllium husk, for eg, which is cheap and effective and has been utilized as a digestive aid in Chinese traditional medicine for centuries (one of the few to survive rigorous empirical evaluation, naturally)
anon84873628 2mo ago
Well, fortunately it's not the only such study: https://prebioticassociation.org/resistant-starch-research-update/ https://prebioticassociation.org/resistant-starch-research-u... Several of those are reviews themselves.

by paimapi 2mo ago

lluisantoni 2mo ago

Also, the authors claim the starch "inhibited lipid absorption." They do not argue why they used surrogate blood biomarkers instead of residual energy output in fecal samples (which is a better measurement). sample size is 37, number of authors 29

dudisubekti 2mo ago

> not generalizable But there's already a general advise on this: eat more fiber. https://med.stanford.edu/news/all-news/2017/08/hunter-gatherers-seasonal-gut-microbe-diversity-loss.html https://med.stanford.edu/news/all-news/2017/08/hunter-gather... We're a great ape, our body evolved to process a lot of fiber from fruits and starches. It's the modern fiber-deficient diet that's really weird. 90g/day of fiber is similar to the Hadza tribe diet, where they can consume 100-150g of fiber per day.

iamacyborg 2mo ago
Fiber’s the new fad supplement.
- dudisubekti 2mo ago
  I hope you're not being serious, but they're not "supplements", they're food. You can easily get them from fruits and vegetables. While they're not essential in short-term survival, they're essential for long-term health: https://www.ncbi.nlm.nih.gov/books/NBK559033/ https://www.ncbi.nlm.nih.gov/books/NBK559033/ We have enough peer-reviewed studies on this.
- arcanemachiner 2mo ago
  I thought we were onto protein now?
  - iamacyborg 2mo ago
    It’s on its way out, fiber’s the new thing.
  - adrian_b 2mo ago
    Eating enough protein is also important, especially for older people, to prevent the loss of muscular mass, but that does not change the fact that the food must also include enough "fiber". The US had for a long time a much too low recommendation of around 0.8 g of protein per kilogram of body weight per day. That has been discredited by various studies. It is an amount that is sufficient to keep you alive, but it is not sufficient to keep you in good health until an old age. It is not known with any certainty which is the optimum amount of protein intake. On certain lab animals protein restriction lengthens life, but for now there is no evidence that this also works for humans. Too much protein is known with certainty to be harmful for humans. I believe that it is likely that the optimum protein intake is somewhere between 1.2 and 1.5 grams of protein per day and per kilogram of body weight, for a person with no overweight. For an overweight person, the protein needs do not increase proportionally to the total mass, i.e. the extra fat does not need much protein. I wonder whether the so low protein recommendation of USA was actually intended for average Americans, which are likely to be overweight, in which case that number might provide an adequate protein intake.
- PunchyHamster 2mo ago
  it has been for a while, a lot of foods advertise fiber
amanaplanacanal 2mo ago
We shouldn't assume that because we are a great ape that we eat the same as other great apes. Humans spent two million years away from the jungle evolving in the savanna, with very different food sources. Our guts changed quite a bit in that time, and our digestion doesn't work the same.
- dudisubekti 2mo ago
  Good thing we're not just assuming, we're actually studying it too: https://www.ncbi.nlm.nih.gov/books/NBK559033/ https://www.ncbi.nlm.nih.gov/books/NBK559033/ Also savannah human diet is chock full of fiber too: baobab pulp, grass seeds, tuber plants, etc
  - adrian_b 2mo ago
    Their is no doubt that for millions of years the humans have eaten much less fiber than their ape ancestors. You just have to look to the belly of a healthy, non-obese human and compare it with the bellies of the apes. The bellies of the apes are much bigger, despite not having the fat of humans, because they have much longer intestines, which are packed in there, which are required for the fermentation of the large amount of fiber included in their diets. The intestines of humans are not so reduced as those of the obligate carnivores, but they are still much shorter than of most apes or monkeys. Our health is still dependent on eating a decent amount of "fiber", but the amount we need is not comparable with what an ape needs.
    - dudisubekti 2mo ago
      I mean yeah, of course. We don't need as much as fiber as gorilla. My point is just modern diet is severely lacking in fiber, when our gut evolved to process them. It's not a surprise this evolutionary mismatch will cause so many problems in our body.
      - adrian_b 2mo ago
        I agree.
paimapi 2mo ago
a starch is not fiber and generally not broken down the same way in digestion afaik fiber is great and under-consumed (especially soluble) and is very well-studied on modern populations [0]. we don't really need to make mechanistic reasonings about evolutionary adaptations that occurred hundreds of thousands of years ago or rely on studies of a small, homogenized population whose lived realities are far from yours and mine plus, following the the hierarchy of evidence, mechanistic guesses are considered extremely low quality, only ranking above things like mouse studies [1] [0] https://www.uptodate.com/contents/healthy-diet-in-adults#H617032519 https://www.uptodate.com/contents/healthy-diet-in-adults#H61... [1] https://en.wikipedia.org/wiki/Hierarchy_of_evidence https://en.wikipedia.org/wiki/Hierarchy_of_evidence
- adrian_b 2mo ago
  "Fiber" is a vague term that is used for the carbohydrates that cannot be digested by humans, so they reach the large intestine, where they are fermented by bacteria. This includes a part of the "resistant starch", which is poorly digested by humans, so a big part of it reaches the large intestine. So yes, the "resistant" starch counts as "fiber", but not all of it, because some part of it is hydrolyzed into glucose, which is absorbed.
  - paimapi 2mo ago
    this is bordering on pedantry but aren't there classifications by different regulatory and medical institutions of what fibers are and aren't? as far as I'm aware, a starch isn't a fiber unless a special exemption is carved out for it and only if that starch meets certain criteria for how it behaves looking into RS's in general, it seems like there is a special carve-out after a lot of industry lobbying for very specific forms of RS's to be classified as fibers and only if they have physiological effects similar to the classic definition of fiber: https://www.fda.gov/media/113663/download https://www.fda.gov/media/113663/download for practical reasons, I suppose I'm just not understanding why you don't eat more 'classical' fibers. psyllium husk, for eg, which is cheap and effective and has been utilized as a digestive aid in Chinese traditional medicine for centuries (one of the few to survive rigorous empirical evaluation, naturally)

anon84873628 2mo ago

Well, fortunately it's not the only such study: https://prebioticassociation.org/resistant-starch-research-update/ https://prebioticassociation.org/resistant-starch-research-u... Several of those are reviews themselves.