- MAC - microbiota accessible carbohydrate
- SCFA - short chain fatty acids
- NNS - non-nutritive sweeteners
- FODMAPs - fermentable oligosaccharides, disaccharides, monosaccharides & polyols
We do have an enzyme called sucrase which splits white-p'ison cane sugar into its constituent glucose and fructose. Every living thing we know about can get energy from glucose, some more efficiently than others. If a large fraction of the carbohydrate intake is sucrose, and it is, then a small fraction of the microbes streak ahead, over-grow and leave nothing for the slower, but biochemically more versatile, bacteria. That limits the amount of interesting compounds that we can harvest or which can encourage a diverse flora capable of withstanding the invasion of a wide variety of pathogens. It's like a metaphor for a healthy society: we all benefit if, rather than subsistence hunter-gatherers, there are pianists, blacksmiths, telephone-sanitisers, life-coaches, bankers, bakers, bus-drivers, PE teachers and rocket-scientists. If we all went out foraging like hunter-gatherers and came back with a variety of leaves, fruit and fungi for dinner then eating would be more interesting and minority bugs would be given a leg up in the struggle for existence in the dark-down-there.
We are subject to a lot of faddy nonsense recommending named diets with supposed but largely untested and aspirational benefits: Atkins, lactose-free, gluten-free, Ketogenic, Lutefisk, Veggie, Vegan, Palaeo, Mediterranean etc. One trouble is that you can make 'bread' without gluten but only with the help of food engineers who lurry in the emulsifiers, stablisers, guar-gum, anti-oxidants to make something that looks like the real thing. The emulsifier polysorbate-80 induced obesity and intestinal inflammation in experimental mice; which is a worry when you consider how widely used the stuff is in value-added packaged food.
Plant-based foods [aka 'food'] are the most likely source of MACs which will help keep your microbial flora a) diverse and b) stable. Diversity probably providing a buffer against the slings and arrows of outrageous incoming bacteria [aka 'disease']. But plants are also a rich source of their own weird metabolism. The same P who recommended this Gentile and Weir article spent a couple of years in Australia studying plant secondary compounds and their effect on fertility in kangaroos. In an attempt to deter herbivory some australian grasses produce phyto-estrogens which trick about with the fertility of female red kangaroos Macropus rufus. Actually, the 'roos have subverted this defensive chemical warfare and seem, after drought-break triggers a flush of new vegetation, to use a jolt of phyto-estrogens to start gestating their young. Move - counter-move: the dance of evolutionary imperative drives us all around the ballroom of life.
Exec summ: "Eat food, not too much, mostly plants" then you can largely forget about the detail of diet.