{"id":3048,"date":"2026-05-24T01:29:26","date_gmt":"2026-05-24T05:29:26","guid":{"rendered":"https:\/\/haidut.me\/?p=3048"},"modified":"2026-05-24T03:05:24","modified_gmt":"2026-05-24T07:05:24","slug":"vitamin-b1-thiamine-may-improve-gut-motility-and-relieve-constipation-ibs","status":"publish","type":"post","link":"https:\/\/haidut.me\/?p=3048","title":{"rendered":"Vitamin B1 (thiamine) may improve gut motility and relieve constipation\/IBS"},"content":{"rendered":"

Gut motility is perhaps the single most important factor controlling\u00a0endotoxin absorption<\/strong>\u00a0from the gut into the bloodstream. Constipation increases gut transit time, allowing Gram-negative bacteria to proliferate and release large quantities of\u00a0lipopolysaccharide (LPS)<\/strong>\u00a0. Endotoxin then triggers systemic inflammation, serotonin release (90% of serotonin is in the gut), and a host of chronic diseases. Ray Peat has long recommended\u00a0raw carrot salad<\/strong>\u00a0(with coconut oil and vinegar) as a gentle, fiber-based way to bind endotoxin and improve motility. I have written extensively about antibiotics (such as penicillin or doxycycline) for more severe cases. Now, a large genetic study published in\u00a0Gut<\/em>\u00a0has identified that\u00a0vitamin B1 (thiamine) metabolism<\/strong>\u00a0is a key determinant of gut motility and IBS risk. While the article focuses on the genetic associations, the real mechanism \u2014 which the authors do not discuss \u2014 is the\u00a0bioenergetic role of B1<\/strong>\u00a0in supporting oxidative metabolism and raising CO\u2082 levels.<\/p>\n

As the study below demonstrates, researchers analyzed data from\u00a0more than 268,000 people<\/strong>\u00a0across six biobanks (European and East Asian) and identified\u00a021 genetic locations<\/strong>\u00a0associated with stool frequency (SF) \u2014 a proxy for gut motility. The top variant affects\u00a0SLC35F3<\/strong>, a gene that transports\u00a0vitamin B1 (thiamine)<\/strong>\u00a0into cells. Another variant affects\u00a0XPR1<\/strong>, a phosphate exporter that is essential for converting thiamine into its biologically active form,\u00a0thiamine pyrophosphate (TPP)<\/strong>\u00a0. Observational dietary data confirmed that\u00a0higher thiamine intake was associated with higher stool frequency<\/strong>\u00a0(i.e., less constipation), and the effect depended on which gene variants a person carried.<\/p>\n

The study concludes that vitamin B1 metabolism plays a “surprising role” in gut motility and opens possibilities for dietary or drug interventions targeting thiamine pathways. But the mechanism is not surprising at all to anyone familiar with bioenergetics.\u00a0Vitamin B1 (thiamine)<\/strong>\u00a0is the essential cofactor for three critical enzymes:<\/p>\n

    \n
  1. \n

    Pyruvate dehydrogenase (PDH)<\/strong>\u00a0\u2014 the rate-limiting enzyme for carbohydrate oxidation. PDH converts pyruvate to acetyl-CoA, allowing glucose to enter the TCA cycle and be oxidized to CO\u2082. Without sufficient B1, pyruvate is instead converted to\u00a0lactate<\/strong>\u00a0(the Warburg effect), producing far less ATP and creating a reductive, inflammatory state.<\/p>\n<\/li>\n

  2. \n

    Alpha-ketoglutarate dehydrogenase (KGDH)<\/strong>\u00a0\u2014 another key enzyme in the TCA cycle, also dependent on B1.<\/p>\n<\/li>\n

  3. \n

    Carbonic anhydrase<\/strong>\u00a0\u2014 B1 is a known\u00a0carbonic anhydrase inhibitor<\/strong>. By inhibiting carbonic anhydrase, B1\u00a0raises CO\u2082 levels<\/strong> in the body. Ray has written extensively about CO\u2082 as a metabolic signaling molecule<\/strong>\u00a0with anti-inflammatory, vasodilatory, antioxidant, anti-serotonin, and anti-estrogen effects. Mainstream medicine still ridicules CO\u2082 as a mere “waste product” \u2014 yet elevated CO\u2082 relaxes smooth muscle, improves blood flow, and reduces inflammation, all of which would directly improve gut motility.<\/p>\n<\/li>\n<\/ol>\n

    Thus, the benefits of B1 for gut motility are likely mediated by two synergistic bioenergetic mechanisms: (1)\u00a0improved oxidative metabolism<\/strong>\u00a0(via PDH and KGDH), which increases ATP production and powers the smooth muscle contractions of peristalsis; and (2)\u00a0elevated CO\u2082<\/strong>\u00a0(via carbonic anhydrase inhibition), which relaxes the gut, reduces inflammation, and counteracts serotonin’s constipating effects.<\/p>\n

    The human-equivalent dose is not explicitly stated in the article, as this was a genetic study, not an intervention trial. However, based on the literature and my previous writings,\u00a0therapeutic doses of thiamine for gut motility are typically in the range of 300\u20131,500 mg per day of thiamine HCl or allithiamine (a fat-soluble form)<\/strong>\u00a0. For those with genetic variants in SLC35F3 or XPR1, higher doses may be required to overcome reduced transport or activation efficiency.<\/p>\n

    This study is a perfect example of how mainstream genetics is finally catching up to what bioenergetic researchers have known for decades:\u00a0vitamins are not just for preventing deficiency diseases. They are powerful metabolic therapies that can treat a wide range of conditions, including common digestive disorders like constipation and IBS.<\/strong>\u00a0The researchers mention “repurposing” existing drugs, but the simplest repurposing is already available over the counter:\u00a0vitamin B1 supplements<\/strong>.<\/p>\n

    https:\/\/gut.bmj.com\/content\/early\/2026\/01\/05\/gutjnl-2025-337059<\/a><\/p>\n

    https:\/\/www.news-medical.net\/news\/20260123\/Genetic-study-links-vitamin-B1-metabolism-to-gut-motility-and-IBS-risk.aspx<\/a><\/p>\n

    “…By analyzing bowel movement frequency in more than 268,000 people<\/strong>\u00a0, researchers uncover how\u00a0thiamine-processing genes shape gut motility<\/strong>\u00a0, link constipation and diarrhea to shared biology, and point to new therapeutic possibilities for IBS and related disorders.<\/p>\n

    “…The top variant affects SLC35F3<\/strong>\u00a0, a gene that transports\u00a0vitamin B1 into cells<\/strong>\u00a0, influencing expression in the brain and digestive tract and potentially integrating central and enteric nervous system control of motility.<\/p>\n

    “…The second variant affects XPR1<\/strong>\u00a0, a phosphate exporter… Phosphate export by XPR1 is\u00a0essential for converting thiamine into its biologically active form, thiamine pyrophosphate (TPP)<\/strong>\u00a0.<\/p>\n

    “…Analysis of 98,449 participants confirmed that higher thiamine intake was associated with higher stool frequency<\/strong>\u00a0in observational dietary data, with the effect depending on which gene variants a person carried. This suggests these genes regulate how the body uses\u00a0vitamin B1 to control gut motility<\/strong>\u00a0rather than acting through a single organ or pathway.<\/p>\n

    “…The study uncovered a surprising role for vitamin B1 metabolism in gut motility<\/strong>. This discovery opens possibilities for\u00a0dietary or drug interventions targeting thiamine pathways<\/strong>.<\/p>\n

    “…Many existing medications, particularly cardiovascular drugs, could be repurposed to treat IBS and other gut motility disorders<\/strong>\u00a0, but further experimental and clinical investigation is required.<\/p>\n","protected":false},"excerpt":{"rendered":"

    Gut motility is perhaps the single most important factor controlling\u00a0endotoxin absorption\u00a0from the gut into the bloodstream. Constipation…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[868,2017,104,1355,97,939,204,203],"class_list":["post-3048","post","type-post","status-publish","format-standard","hentry","category-science","tag-co2","tag-constipation","tag-gut","tag-ibs","tag-metabolism","tag-motility","tag-thiamine","tag-vitamin-b1","wpcat-2-id"],"_links":{"self":[{"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/posts\/3048","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/haidut.me\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3048"}],"version-history":[{"count":2,"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/posts\/3048\/revisions"}],"predecessor-version":[{"id":3056,"href":"https:\/\/haidut.me\/index.php?rest_route=\/wp\/v2\/posts\/3048\/revisions\/3056"}],"wp:attachment":[{"href":"https:\/\/haidut.me\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3048"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/haidut.me\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3048"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/haidut.me\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3048"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}