Larc400 wrote:Elliot, do you have any deficiencies?
Part of the reason I suspect SIBO in my case is that I have a B12 deficiency for which they have not found the cause in spite of performing numerous tests (gastro+coloscopy etc). I'm also verging on low Iron. Both of these despite an average diet.
I also get incredibly tired, and I mean incredibly, 1-2h after eating, even though glucose levels are okay.

Hi there. I literally just made an account to respond to your post. I know it's oooold but this could be still useful to you or someone else.
Please look into hypochlorhydria, AKA low stomach acid. All the things you listed are its symptoms (tiredness after meals, b12 and iron deficiencies), along with other deficiencies despite sufficient dietary intake, lack of appetite in the morning, belching for hours after meals, constipation/diarrhea, nausea, reflux, lack of appetite for meat, undigested food in stool... and bad breath, obviously.
Basically, without stomach acid food sits in your stomach undigested for hours so you're not hungry in the mornings because you still haven't digested your evening meal. Until the ph gets to a certain level, the stomach won't empty which raises pressure and causes reflux, both bile and acid. You're unable to absorb nutrients like iron, b12, vit. d and others, and because pepsin (necessary to break down proteins into aminoacids) also needs a proper environment to work, meat and other high-protein products make people with this problem feel particularly bad so they often cut out meat from their diet completely. It may also cause SIBO. I've been looking into this lately as my years-long GI issues are worse than ever and so is my bb lately. Apparently betaine supplements work as digestive acids when taken with meals, I just got one and hope it will work, as I'm feeling really f**king awful and losing weight. Mine is with digestive enzymes too. Not sure if there are meds for this, the page I read about it (some doctor's blog, will post a link once I'm on my laptop) said gastroscopy won't diagnose lack of stomsch acid and neither will most doctors because they're so fixated on its OVERproduction, due to PPIs being pushed everywhere. Apparently most people who take thrm actually have too little, not too much acid. Hopefully this helps someone.