Hydrogen Sulfide SIBO: Ending the Toxic Gas Attack in my Gut
Like many people with chronic digestive issues, I’ve been through multiple cycles of treating methane SIBO — only to have it return again and again. It wasn’t until I followed a chain of clues through test results, failed treatments, homemade yogurt, sulfur compounds, and genetic variants that I finally uncovered a key breakthrough: hydrogen sulfide SIBO.
A Rough Start With a Standard Protocol
My doctor ordered a breath test and confirmed that I had methane-dominant SIBO. That part wasn’t a surprise — I’d had it before, and it always seemed to come back. We started a standard herbal anti-SIBO protocol, but after just one dose, I developed severe gas and acute diarrhea. My digestion didn’t bounce back quickly — it took nearly a month to stabilize.
Clearly, this treatment was far too strong for me. So I switched gears.
Probiotic Yogurt: A Gentler Approach
I went back to something I had read about before: an anti-SIBO yogurt recommended by Dr. William Davis (of Super Gut fame). You make it yourself using a mix of specific probiotic strains. I took it for about a month, and it seemed to help — my symptoms improved more gently and consistently.
But something still didn’t add up. The gas I had experienced had a strong hydrogen sulfide, rotten-egg smell — and I remembered reading that hydrogen sulfide can feed methane SIBO. That connection stuck in my mind.
Connecting the Clues: Hydrogen Sulfide
I discussed the situation with ChatGPT and explained my symptoms and history. It suggested trying a low-sulfur diet for a few weeks — something I hadn’t ever thought of. We worked around my dietary restrictions and created a low-sulfur plan I could actually follow. I also stopped taking sulfur-heavy supplements like NAC-ET.
The results were rapid and dramatic. Within a week, I noticed a huge improvement — not just in digestion, but across multiple systems. My skin, which is usually a strange yellowish tone unless I’m doing regular sauna sessions or taking NAC-ET, actually looked like a normal person's. I felt clearer-headed and far less inflamed — as though a cloud had lifted. It felt like a reduction in oxidative stress, if that can be sensed viscerally.
A New Layer: Genetics and Detox
As often happens, fixing one thing revealed another imbalance. My muscle pain began increasing again, and I suspected it was due to stopping NAC-ET entirely. I restarted it cautiously.
At the same time, I learned that I have a genetic variant affecting molybdenum uptake (MOCS1). Molybdenum is critical for sulfur detoxification. Without enough of it, excess sulfites can build up and get metabolized by sulfur-loving bacteria into hydrogen sulfide gas — which then feeds other bacterial overgrowth in the small intestine. Meanwhile, this internal gas attack was happening entirely inside my gut and went unnoticed for years.
I also discovered a variant affecting glutathione recycling (GSR), which may explain why I was drawn to eating high-sulfur foods like broccoli and supplementing with NAC-ET (which promotes new glutathione production). In hindsight, I was unknowingly adding fuel to the fire — trying to combat the effects of oxidative stress with sulfur-based tools that were worsening the root problem.
I’ve since restarted molybdenum, which supports the sulfite-to-sulfate conversion pathway and may help buffer the effects of sulfur overload.
Where I Am Now
This was a major breakthrough — identifying and addressing hydrogen sulfide SIBO helped resolve long-standing symptoms that had never improved with conventional treatments. My thinking is clearer, my skin is visibly healthier, and my digestion is significantly more stable. This was a massive source of toxic load that had been completely invisible until now.
I’m still optimizing. With chronic illness, progress often means fixing one thing and watching something else shift or break. But this time, the direction feels right.