I have been reading some here lately that vitamin D deficiency is thought now to be related to ibd/ibs and other gut issues. I got my levels tested earlier this year and mine were very low so I started taking 1000ius daily. Not sure if it's helping my gut because I'm still having issues but it definitely helps my energy which is why I went to the Dr when they found my deficiency. I asked Dr why my levels would be low and he wasn't sure but said maybe leaky gut? I think I may need to take my dosage down because it may be irritating my gut. I'm getting levels tested again in December and will see.
Anyway i think there is a connection and is interesting. Has anyone else experienced something related to this or read about it? Here is one article. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6116667/