“Levothyroxine therapy and impaired clearance are the strongest contributors to small intestinal overgrowth “ by Brechmann, Sperlbaum & Schmiegel, 7 Feb 2017.
Having battled SIBO for years, looking back it definitely got worse after I went on Levothyroxine. I had no idea that Levothyroxine itself is even more associated with SIBO than hypomotility , and that Levo is a stronger predictor of SIBO than hypothyroidism. And I have been deluding myself then in thinking that if I get my Levo dose optimal my gut symptoms will improve! Instead, every dose increase has made the SIBO worse!!!
Unbelievable.
[edited by admin to add a clickable link to the paper]
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bluejourney
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I’ll throw a theory into the ring but I’m not wedded to it, I skimmed the study very briefly.
Maybe levothyroxine can make people more prone to continued SIBO because it under replaces us? Many people find that they do better on their declining natal thyroid hormones over levo replacement (I know I did) because T4 mono dictated by TSH is basically a recipe for undermedication. It’s compounded by the fact that instead of just giving people T3 too or suppressing TSH, they give people PPIs to cope with reflux from chronic low stomach acid... a common product of being hypothyroid. (I saw PPIs were also positively correlated in the study with SIBO.)
To correct SIBO I would do -
- Optimize thyroid hormone replacement
- 3 months LOW FODMAP
- Encourage gastric juices & enzymes using bitters and digestive supplements
- Use gentle laxatives such as Magcarbonate and watch the sunrise as far as possible to ensure daily elimination and healthy peristalsis
- Include raw carrot salad daily
As a side note - this study really shocks me, when I worked at the Royal Free in 2019 as a nutritionist they wouldn’t even accept that SIBO was a real condition.
All my prayers go on a super-thyroid-bug plague sweeping all the ignorant endo offices (endos who are protected need only pin their given T3 prescriptions above their doors and the plague will leave them alone) rendering them “subclinical” raising their TSH no faster than 0.01 every 2 weeks until they are depressed, fat, balding, anaemic, cold, dry, constipated, fatigued, anxious, nutrient-depleted husks pleading for help, only to be turned away by the TSH.
I’ll spare a few extra prayers for a SIBO plague 👍
This is so interesting. Are you able to elaborate on the benefits of daily carrot salad? Is it to do with the vitamin C content? And would carrot salad basically be grated carrot?
Use gentle laxatives such as Magcarbonate and watch the sunrise as far as possible to ensure daily elimination and healthy peristalsis
Can you please expand on the ‘watch the sunset’ part of this…..am I to read this literally or is it a metaphor? Thanks 🙏
The daily carrot salad is coconut oil, vinegar and grated length ways carrots with some salt. There are no studies to back this up, (only patient reports on Ray Peat forums) but it is said that the carrot fibre can act as an intestinal pipe cleaner 🧼 dragging out toxins (estrogen in particular - but again, no studies to back this, just women with estrogen dominance in RP forums). It’s a pretty low risk investment, so even if it doesn’t help you’ll still reap the benefits of eating something generally healthy.
Watching sunrise - Jack Kruse argues that watching sunrise provides input through the eyes to the suprachiasmatic nucleus (like a pacemaker in the hypothalamus) to trigger circadian-dependent processes. All our cells have a clock on them, they all secrete and expect different substances and processes at different times of day (eg. Healthy person secretes T3 around midnight, cortisol around 4am etc etc.) and one of the greatest inputs that triggers these time-dependent processes is light. Sunrise has a particular spectrum of light that triggers processes. Peristalsis is said to be deeply connected to light, hence why most people have their bowel movement in the morning. 🙂
Woah! I feel compelled to bust out the following: 🤯 🤯🤯
Thanks very much for the thorough response. I’ll certainly try the carrot salad, as you say, even if the benefit in terms of gut health is benign, I’ll have incorporated something delicious into my day.
Living on the east coast, I’m uniquely located to observe the sun rising before the rest of the country….if only I could persuade my groggy headed self to comply!
Start with sunset, it’s a lot easier at that end of the day 🙏 get some blue light blocking glasses on after you watch the sunset, don’t have any artificial light input into your eyes after sunset, candles are allowed 🕯️Victorian style. Do it for a month and watch how your sleep transforms - it’s brilliant. The coast sounds an idyllic place to begin experimenting 🌅
I would agree with Hidden many thousands of thyroid patients are either under replaced with levothyroxine and/or poor converters of Ft4 to Ft3 and/or very low vitamin levels
Standard treatment of hypothyroid patients frequently results in low stomach acid……and far too frequently this is made worse by medics prescribing PPI lowering stomach acid further and resulting in even lower vitamin levels
What shocked me was the finding that Levothyroxine was more associated with SIBO than being hypothyroid. All those other things you mention would be factors whether you were under replaced and still hypothyroid or undiagnosed and hypothyroid, but it was being on Levo that was the strongest predictor of SIBO.
Interestingly, my stomach acid is too high, (got it tested on the Heidelberg test, in which they give your stomach an alkali challenge ), so I can’t blame low stomach acid for the SIBO, and I don’t take any other Meds except for a low dose of Fludrocortisone for low BP. I do still feel under replaced though, but I’m not sure now that an increased dose of Levo is the answer. Still waiting for a printout of my latest NHS hospital test results. Endo says I’m over replaced because TSH suppressed, I’m saying I’m under replaced because my FT3 is only 27% through reference range. Will post my results when I get the printout.
I expect he did. The majority of endos don't even know what T3 is - and a lot of them are dead set against prescribing it! They say 'it doesn't work', which doesn't even make sense. But, they'd say anything to avoid prescribing it.
This NHS endo knew what T3 is, but didn’t know what SIBO is. As well as many consultants being antagonistic towards T3, I’ve found most doctors are totally ignorant about SIBO. The last NHS gastroenterologist I saw had never heard of methane SIBO, which is what I’ve got, diagnosed 2017. Could only offer me a hydrogen breath test. So it’s pretty much hopeless expecting they’ll see the connection between SIBO and hypothyroidism actually. I’ve found to save disappointment it’s best to go to an NHS appointment with no expectations whatsoever.
I was very surprised this study uses the term SIBO/concedes its exists, I expected the journal to be alternative or fringe but it’s mainstream reputable (not that that means that much really but it means something to others). I’ve never met a gastro who accepts it, I’m sorry. What have you tried for it?
Things that have helped my SIBO: going lactose free and gluten free, the low fodmap diet - works but a bit of a cut-de-sac - a course of caprylic acid plus (wise Owl), a course of Metronidazole, Dr William Davis’s Super Gut SIBO yoghurt (from his book Super Gut), and currently on a course of Rifaximin, am also taking curcumin and NAC at the same time.
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