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Do foods with preservatives stay digestible for longer in the gut by not rotting as much (producing less toxins)?

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Hi @Jo Rijo, I edited your question to have better grammar and is now clearer. I'm not sure what you meant by the last sentence, from "doesn't start becoming toxic as fast thus the gut doesn't expel it as fast?" Can you clarify this please? Also, conservative is a poltical party, and preservatives prevent food spoilage. ;) – user560 Oct 27 '12 at 23:29
Please note that expulsion of feces is NOT at all due to food spoiling and becoming toxic. – nico Oct 28 '12 at 15:56
@leonardo thx, I edited again, hoping it's clearer now. to clarify what you requested: I mean if the food has preservatives, then maybe it prevents the food decomposing as much as it would if it didn't have preservatives, thus not becoming as toxic as fast, thus the gut doesn't expel it as soon. hope that is clearer. But in the mean time nico has said what he said, but I don't really agree, I thought it was common knowledge that the intestines expel "stuff" that is sufficiently toxic, at least certain toxins, so... – Jo Rijo Oct 28 '12 at 19:45
@JoRijo no, that isn't the case :-) I think your question is interesting but you might not get the answer you're looking for as your premise is incorrect. – Rory M Oct 28 '12 at 20:11
what a mess :P I've done some more research and it was believed that food in the gut putrified and became toxic up until early 20th century when advances in science showed no evidence of such. – Jo Rijo Nov 12 '12 at 18:35

Do foods with preservatives take longer to digest?

Food preservatives are either antimicrobials (e.g. sorbate, sulfite) or antioxidants (free radical scavengers such as butylated hydroxyanisole).

Digestion is initiated in the stomach by hydrochloric acid and pepsin. It continues in the small intestine with the action of numerous other enzymes including amylases, lipases and proteases. There is no obvious way that these digestive processes would be inhibited by preservatives.

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Can you please provide any proof of this? It is by no means obvious that and antimicrobial could not have an effect say, on intestinal blood flow... – nico Oct 28 '12 at 14:10
You can only exclude specific effects. And you're right in suspecting that not all is well with food additives. Lots of people have intolerance/allergies to them. In general however, the answer is correct and if it weren't, the food industry would be buried with paper by lawyers. – rwst Oct 28 '12 at 14:45
@rwst: not necessarily. An additive can modify absorption of food without having necessarily negative effects. For instance, EDTA is sometimes used as a preservative, and it does halve absorption of non-heme iron. – nico Oct 28 '12 at 15:59
Absorption isn't digestion. – Alan Boyd Oct 28 '12 at 16:02
Hum... well the antimicrobials, if they kill some of the helpful gut bacteria then It'd be expected that they affect the absorption rate negatively, right? – Jo Rijo Oct 28 '12 at 19:37

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