Yes, it does. Saying that it does not enter the equation at all
I think we have a failure to communicate here. For the second time you fail to acknowledge the sentence "or perhaps only insofar as a fraction of the appetite is concerned". Are you doing it on purpose ?
is saying that it makes no difference how much is absorbed, even in severe malabsorption conditions. You claim that people with a lower absorption rate compensate by eating more, and that it therefore does not enter the equation at all, is claiming that the absorption rate can be safely ignored. I don't think there is any evidence that are able to compensate a lower absorption rate in this way.
1. You said I ignored the absorption rate's contribution to appetite, which I clearly didn't. However, I still maintain that its contribution is minimal. Yes, for Ed's sake, you can completely leave it out of the equation as far as any practical diet is concerned.
2. You mentioned malabsorption, when I clearly said I don't talk about such conditions.
3. If (and that's a completely hypothetical "if") absorption rates were significantly different, then yes, I claim those people with lower absorption rates would compensate by eating more. It's pretty simple: They would be needing more energy.
I can't find any large measurements of individual differences of nutrient absorption rates, but it would be weird if they don't exist; all other phenotypical properties show significant variation.
However,
here is a study about differences between enthnicities and possible influence of light levels in carbohydrate digestion.
here is a study that indicates that it changes with age.
Not only you won't be finding any meaningful measurements of the kind, but even if you did this wouldn't mean much. Because it would still be only relevant to the very small fraction of appetite that is relative to the volume of the food. We've had a similar discussion in the past with Blutoski, during which he suggested the book "Volumetrics" by Barbara Rolls, based on that very idea. I got and read the book and was rather underwelmed. I may offer some critique on the studies she cites vs the conclusions she draws.
Besides, it doesn't take a genious to realize that increased food volume hasn't worked very well for dieters so far. And it's not like it's a new idea either.
BTW, there's one more inacurracy which I haven't brought forward so far because the whole point is rather insignificant. But in any case, absorption is primarily a function of the gut, while appetite control via food volume is focused on the stomach.
It is also well known that how much is absorbed also depends on what you eat. Some substances increase or inhibit the absorption of other substances.
Not in any way that would be useful to a dieter. Unfortunately, the most valid way to reduce the absorption rate of macronutriets is to overeat in a small period of time, which defeats the purpose.
How much nutrients are available to the body also depends on the intestinal flora.
Here is some evidence from animal studies that suggests that your weight is partly dependent on which bacteria are living inside you, because they influence how much nutrients are available to absorb.
You are attaching too much importance to factors that may be responsible for a a very small percentage of the total dietary deviations in one person's diet. Even in the last study you cited the researcher admits that "The amount of calories you consume by eating, and the amount of calories you expend by exercising are key determinants of your tendency to be obese or lean".
That's not quite true. Obesity surgery still has a fairly high failure rate because people can eat more. It just makes it really uncomfortable to eat more in one go, but unfortunately that does not stop all people.
On the contrary, this is exactly why what I said is VERY true. Stomach stapling makes people sick when they overeat, and this is why they end up taking less calories. The fact that they can gradually re-adjust to increased intake is totally different.
"They CAN'T eat more, that's why they don't." is misrepresenting how it works.
Boy, I don't know what to say. You've completely twisted the meaning of my sentence. "They CAN'T" was meant to have the same meaning as your (revised) statement "It just makes it really uncomfortable ". I already said "The main way this works is by making people feeling ill when they eat more". It's not "CAN'T" like "it's physically impossible". As opposed to what you previously said "That doesn't necessarily cause people to feel hungry and eat more."
If filling the stomach was adequate in reducing appetite, then nothing would be much easier. People have been unsuccesfully trying such methods for ages. Fiber that absorbs water, salads, water, etc. We've already tried this.
Obviously. It also suggests that there is more to the control of appetite than how much nutrients are absorbed, which is why you can't say that the absorption rate "doesn't enter the equation at all".
Not in any worthwhile degree, no matter what you say.
If you still have a point to make, please make it consice: Are you saying that different absorption rates are an important factor in determining whether one will develop obesity ? Yes or No ? Because I have the feeling that you are trying to find something to disagree with me. I have never questioned that appetite varies greatly between people. Hell, even my own appetite would only be satisfied at about 800-100 kcals above my maintenance level. But food volume and absorption rates are only very minor contributors to this, if at all. Do you disagree with my basic position that there's nothing in a healthy person's metabolism preventing him/her from losing fat (even hypothyroidism is responsible for only a 5-10% reduction in basal metabolism) ? Do you know that the number 1 reason diets fail is underestimating of ingested calories ? Because it seems to me a little strange that "absorption rates" is all you have to comment on, out of everything that has been said here.
