Freddy,
YES, there is a big correlation between low vit.d3 and IBD.
Lots of studies out there too.
How low was your vit. d3?
When I first got tested, mine was at 29.
Since then, the doc prescribed 100,000 I.U. of D3 every 10 days.
Thereafter testing resulted in levels of 65-69, which is great.