Posted on Mon, 8 Aug 16
Vitamin D supplements could be a very effective way to relieve digestive symptoms according to the first study in people with irritable bowel syndrome.
Irritable bowel syndrome (IBS) is the name for “unexplained” digestive symptoms such as abdominal pain, bloating, distension, diarrhoea and/ or constipation. Although IBS is considered an enigma it actually has several overlooked possible (and treatable) causes, and vitamin D deficiency can now be added to the list.
Vitamin D deficiency is very common, affecting around 30% of the general population, which, incidentally, is about the same frequency of people that have symptoms of IBS. Previously people have reported feeling much better when they take vitamin D, but no clinical studies had yet tested these anecdotal reports.
A double-blind, randomized, placebo-controlled study looked at whether or not a dose of 50 000 IU vitamin D3 fortnightly (just under 3000 IU per day) for a period of 6 months would help and it did, surprisingly well.
Vitamin D supplements resulted in significant improvements in IBS symptoms such as abdominal pain and distention, flatulence, rumbling, and overall gastrointestinal symptoms (except dissatisfaction with bowel habits), when compared to the placebo group. Abdominal pain responded better than any other symptom. And overall IBS symptom scores as well as quality of life scores significantly improved.
Perhaps not so surprising, most (65%) of the participants were vitamin D deficient at the beginning of the study but only the group taking vitamin D had a better blood level at the study end. And, importantly, those with lower blood vitamin D tended to respond better to the supplements, suggesting that vitamin D may help those who are deficient the most.
The study authors hypothesize that vitamin D might reduce symptoms by lowering mucosal inflammation in the gut, “which can perturb the sensory– motor system of the gut, alter gut function, and cause visceral hypersensitivity responsible for IBS symptoms.”
Abbasnezhad A, Amani R, Hajiani E, et al. Effect of vitamin D on gastrointestinal symptoms and health-related quality of life in irritable bowel syndrome patients: a randomized double-blind clinical trial. Neurogastroenterol Motil. 2016 May 7. doi: 10.1111/nmo.12851. [Epub ahead of print]