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0 pointsdredmorbius12y ago0 comments

It's not merely the quantity, but the rate of assimilation, including gastric emptying, which matters.

So, yes, qualitatively there is a difference not only between eating an apple and a glass of apple juice representing 8 apples, but even when you're juicing a single apple, because that fructose hits your bloodstream immediately.

Useful if you're a bonking cyclist or a runner who's hit the wall. Not so much if you're leading a sedentary lifestyle.

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pvnick12y ago

You didn't specify the effect you're talking about, you were very hand-wavey and just said "matters," which is so broad and general that you could be literally anything. I'm talking about calories. Whether you drink 500 calories of apple juice or eat 500 calories of apples you're still taking in 500 calories [1]. So insofar as caloric retention is concerned, no, that does not "matter."

[1] http://www.bodyrecomposition.com/fat-loss/the-energy-balance...

dredmorbiusOP12y ago

you were very hand-wavey and just said "matters"

Affects insulin levels, insulemic effects etc.

The point is that quantity alone is not sufficient consideration, quality also must be taken into account.

I could be arsed to dig up a bunch of references, but frankly I'm not ego-attached to this issue right now. That said:

https://duckduckgo.com/?q=effects+of+gastric+emptying+on+ins... https://duckduckgo.com/?q=effects+of+insulin+levels+on+morta... https://duckduckgo.com/?q=effects+of+insulin+levels+on+fat

... might give you some interesting starting points.

What matters when you ingest those 500 calories is what they're allocated to, and there endocrine responses (as well as body store availability) does matter.

500g of carbohydrate dumped in the bloodstream of an individual with depleted skeletal muscle and hepatic glycogen stores will have a different response (glycogen uptake in these tissues) than in an individual whose glycogen stores are already saturated (conversion to triglycerides and storage as fat).

Gastric emptying and rate of release matters as you're consuming roughly 15-25g of carbohydrate hourly in your brain (and a few more grams in other tissues). So that an ingested bolus of 500g cho released over the course of 5 hours is going to _largely_ simply result in uptake to tissues with an existing demand, rather than lipogenesis.

No, you can't say fuck you to thermodynamics, but you can dance the funky chicken around it.

darkarmani12y ago

Your link talks about the thermic effect of food. The TEF of apples vs apple juice is definitely different. But maybe that's what your are saying -- calories aren't the important piece?

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