Thiamine (Vitamin B1) improves fatigue in patients with IBD.
Thiamine (Vitamin B1) improves fatigue in patients with IBD.

Thiamine (Vitamin B1) improves fatigue in patients with IBD.

By Marianne Otterstad, Trainee GI physiologist

Fatigue is common in patients with inflammatory bowel disease (IBD), even when the disease is in remission up to 50% of patients still report it (1).

The cause of fatigue in these patients can be related, for example, to iron, vitamin B12 or folate deficiency, anaemia, and hypothyroidism. However, most patients have not identified an underlying cause and few pharmacological drugs have a documented effect on fatigue in IBD patients (1).

A recently published study found a significant decrease in fatigue in patients with IBD in remission who were receiving high-dose oral thiamine (2). The 40 patients enrolled did not have any underlying cause of fatigue and were given 600-1800mg thiamine hydrochloride (dose dependant on gender and body weight) for 4 weeks. The study was a double blinded, placebo-controlled crossover trial. Improvement in fatigue (decrease of ≥3 points in Inflammatory Bowel Disease-Fatigue Questionnaire) was seen in 55-75% of participants whilst on thiamine (2).

The mechanism behind thiamine helping fatigue in IBD is unknown, but it is hypothesised that IBD patients have impaired thiamine transport from blood to mitochondria, hence taking thiamine supplements increases cellular carbohydrate metabolism. Thiamine is a water-soluble vitamin, also known as vitamin B1, that is found in meat, legumes, and dairy products. Bager and colleagues concluded that thiamine was well tolerated, and only mild side effects were reported. Also, thiamine accumulation is not a risk in patient with normal kidney function.

A smaller unblinded pilot study with 12 participants was published in 2013 and found the same effect of thiamine on IBD patients in remission (3). This study also reported an improvement in bowel symptoms after 20 days of high-dose thiamine. Bowel symptoms like abdominal pain and bloating are commonly reported by patients with IBD in remission. This is often caused by small intestinal bacterial overgrowth (SIBO) or lactose intolerance (4). Both SIBO and lactose intolerance can easily be diagnosed from a hydrogen and methane breath test.

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  1. Borren NZ, van der Woude CJ, Ananthakrishnan AN. Fatigue in IBD: epidemiology, pathophysiology and management. Nat Rev Gastroenterol Hepatol. 2019;16(4):247-59.
  2. Bager P, Hvas CL, Rud CL, Dahlerup JF. Randomised clinical trial: high-dose oral thiamine versus placebo for chronic fatigue in patients with quiescent inflammatory bowel disease. Alimentary Pharmacology & Therapeutics. 2021;53(1):79-86.
  3. Costantini A, Pala MI. Thiamine and fatigue in inflammatory bowel diseases: an open-label pilot study. J Altern Complement Med. 2013;19(8):704-8.
  4. Shah A, Morrison M, Burger D, Martin N, Rich J, Jones M, et al. Systematic review with meta-analysis: the prevalence of small intestinal bacterial overgrowth in inflammatory bowel disease. Aliment Pharmacol Ther. 2019;49(6):624-35.