Indeed, GS, you're right to hint that RS can help with metabolizing carbs, as it feeds GI bacteria that then help with the production or absorption of SCFAs, vitamin B6, zinc, Mg, calcium and other nutrients that assist in metabolizing carbs and blunting post-meal BG. And resistant starch is just one of multiple prebiotic elements of raw Paleo foods. (If anyone is interested in the research on this, it can be found pretty easily by Googling on any of these nutrients and "resistant starch").
One reason RS is an especially important prebiotic in Paleo circles is that raw RS intake (and raw animal starch intake) happens to be much lower in the diets of many "Paleo" (and SAD) dieters than in those of Stone Age ancestors (which accumulating scientific research has been documenting, even among Neanderthals--see the study that Tyler helpfully linked to at
http://www.rawpaleodietforum.com/general-discussion/humans-naturaloptimal-habitat/msg120122/#msg120122 -- whom some scientists mistakenly assumed in the past were essentially carnivorous), because starch phobia is so common in Paleo circles, due in part to the promulgation of the myth that all starch converts to sugar and that all sugar = poison at any intake level. On the bright side,
raw Paleo dieters likely consume more prebiotics than cooked Paleoists, because
raw plant
and raw animal foods contain the maximum levels of prebiotics. This is one reason why prebiotics are such a good selling point for the raw aspect of raw Paleo.
It's strange that no RPDers seem to be taking advantage of this prebiotic selling point in persuading others about RPD. It's also odd that cooked Paleo/Primal Blueprint/LC dieters talk about raw foods containing the highest prebiotic levels, and then go right on cooking the hell out of most of their foods, over-relying on the small amounts of retrograde prebiotics they can manage via cooling and reheating.
Another nice thing that the gut bug nutrients like SCFAs and B6 do is make the body more resilient to insults from toxins, such as from plant toxins/antinutrients and cooking toxins. This presumably could enable one to eat some cooked non-Paleo foods to be sociable without suffering significant ill effects as a result.
Another factor in the low intakes of RS in modern diets is that domesticated plants tend to contain less RS and other prebiotics than the wild foods of the past. Thus, it's not easy to consume as much as our ancestors did.
I have noticed that multiple Paleo/LC dieters who assumed the were getting enough RS and other prebiotics in their diets weren't getting anywhere near as much as Stone Agers reportedly did, and I have yet to see a single Paleo or LC dieter guess right about which foods contain plenty of RS. They typically guess foods that are rich in inulin. Inulin is another beneficial prebiotic, but it's separate and distinct from RS. Diversity in prebiotics enables bacteria cross-feeding that produces synergistic benefits.
Some LCers who thought they were super healthy also found that their GI microbiomes were subpar when they got them tested. So even if the body feels great, the GI bugs (Old Friends) may not be so well off.
Microbes reportedly account for around 90% of human cells. Not feeding those 90% well doesn't make sense.
It occurred to me that beneficial bacteria might also help with the digestion of fats, so I just Googled it, and sure enough:
"
Fungi and bacteria may secrete lipases to facilitate nutrient absorption from the external medium (or in examples of pathogenic microbes, to promote invasion of a new host)."
http://en.wikipedia.org/wiki/LipaseProbiotics are also important, to help increase the number of good microbes in the gut to eat the prebiotics, as Dr. BG pointed out:
Taking PS for some (like ANYONE WHO HAS HAD A SINGLE ROUND OF ANTIBIOTICS or eats CAFO antibiotic-laced meat/dairy)… is like a zookeeper feeding EMPTY ZOO CAGES. http://freetheanimal.com/2013/12/resistant-primer-newbies.html#comment-548895