Soluble fiber, or apples, or the simple sugar in apples, or all of these things could plausibly affect stool composition directly via bulk, and indirectly by regulating peristalsis. I think there may even be an indirect-indirect effect via the mind. Mental state is known to affect IBS and motion of the gut. If the apple made you feel good and/or you believed it was helpful, then you could get a reduction in IBS like symptoms (like stool formation), even though the UC was unaffected. This is not a simple placebo effect, but a manipulation of the brain-gut connection.
However, even if the idea of mind-gut is used to affect peristalis more quickly than the bola of food moving thorough the GI tract, we would also need to posit that not only motion, but the rate of absorbing water was affected. IT is possible, we know rather little about
the mind-gut connection. But now the theory is getting more complex.
It is also possible that someone eating apples regularly, after noticing some benefit, is eating apples every day at about
the same time. It might be that the "benefit" observed a few hours after eating an apple is actually the benefit of yesterday's apple, and that there will be a similar benefit tomorrow form today's apple.
one website said ... said...
Physiology of Peristalsis
Peristalsis begins when a bolus, or mass of chewed food, is swallowed, triggering a reflex of smooth muscle action. Nerves are stimulated in the digestive tract that cause smooth muscles to contract above and relax below the descending food, pushing it through the system. The bolus moves from the mouth to the esophagus to the stomach, where it mixes with digestive juices and other digestive agents. From there it descends to the small intestine, where it mixes with bile and becomes chyme. In the small intestine, chyme is processed in the duodenum, passed to the jejunum, where carbohydrates and proteins are absorbed, and to the ileum, where iron and other nutrients are absorbed. It then passes to the large intestine, where water is extracted, and out of the body through the rectum.
Read more: http://www.livestrong.com/article/517213-foods-that-stimulate-peristaltic-motion/#ixzz2CItaG0Ja
I am glad stereo has something that seems to help. But comments like Quincy's ("They wouldn't have an impact on your stool a few hours later") are really, really, (did I mention really) valuable.
There is no magic. If something "works" faster than physiologically/biologically possible then it is either coincidence, something else working, or it is working in some way other than commonly thought (e.g., like the mind-gut scenario I mentioned above).
I remember when stereo posted that a shot of aloe vera juice could stop painful symptoms in 20 minutes. I never said it didn't, but I did discuss that the usual topical anesthetic and anti-inflammatory action could not travel to the colon in 20 minutes. This would require a theory that the drug worked internally in some manner different from the way it worked externally. Or a theory that this was more of a mind-gut thing.
Anyway, always think about
"how" something is supposed to be helping.