some personal research led me to this study: http://www.ncbi.nlm.nih.gov/pubmed/9843779
It connects the SCFA concentration inside the colon with bowel transit time. And it appears that SCFAs have an inhibiting effect and significantly reduce colonic motility.
My take: The gut tries to absorb as many butyrate as possible and therefore slows down the transit process, what do you say?
I actually wanted to mimic this effect with constant butyrate supply and ate lots of ghee with every meal. And indeed - it slowed things down. Maybe someone has experienced similar effects?
Is it possible that dietary MCT and SCFA induce ketone body production and therefore inhibit thyroid function which decreases colonic motility? (http://www.ncbi.nlm.nih.gov/pubmed/15788986) But I'm not sure whether ketones reduce thyroid function, that's just a guess - still looking for a study.
asked byThomy (2384)
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on February 29, 2012
at 08:25 PM
SCFA are present in the colon, but probably only as fermentation by-products. Thus, the slowing transit time probably has more to do with your body trying to ensure that, when it senses fermentation is taking place, it gives the fermentation process enough time to extract every available calorie from otherwise indigestible fiber.
By the way, slow transit time might not be all good. I know it may slow any spike in blood sugar post meal, with the result that it may help diabetics manage their blood sugar. But, it's not clear longer digestion times are otherwise that good. One problem that I know of personally is that it increases GERD.