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Galacto-oligosaccharides (GOS)

Your enzymes in the small intestine can’t digest GOS, but your colon bacteria can. When the bacteria ferment GOS, they produce short chain fatty acids. You absorb some of those. Not much, but not zero.

Rough numbers:

• If you digest a normal carb enzymatically: you get almost all the calories.
• If bacteria ferment it: you get maybe five to ten percent.

So beans and lentils do give you calories. Just not from the GOS. Most of the calories come from the protein and starch in the legumes, which you enzymatically digest the normal way.

If GOS were the whole bean, no one would eat legumes for energy. Luckily for humans, the part you can’t digest is small compared to the part you can.

GOS passes through the small intestine undigested, then gets fermented by colon bacteria, which produces gas and short chain fatty acids. Those fermentation products change the osmotic balance in the colon, pulling in water. The mix of gas pressure and extra fluid is what creates bloating, urgency and loose stools in people who react strongly.

Everyone fails to enzymatically digest the GOS in beans and lentils, but people react differently because if your colon bacteria ferment GOS more aggressively, then more symptoms.

So I’ve got more aggressive bacteria which is different to the old story of an underperforming digestion. I can’t say I don’t digest beans anymore.

Chicken goes straight through me because it has almost no fat, almost no bulk, so it empties quickly from the small intestine and the enzymes barely get started before the leftovers hit the colon.

The bacteria finish the job and make the sulfur smell. This never happens with red meat because it breaks down slowly in my small intestine, leaving nothing downstream.

Other people get away with chicken because their stomach holds it longer, their enzymes chew through it faster or their colon bacteria are less dramatic.

So I did an experiment. I hadn’t eaten for over 12 hours. Then I ate a chicken wrap. 35 minutes later I did my first chicken fart. For most people that passage through to the colon takes 2 hours or more. So I’m quick for whatever reason.

In summary, the GOS intolerance informs me that my bugs are very active. Which probably also explains the chicken issues, compounded by fast passage of said chicken.