b-vitamins

Broadly speaking, having UC doesn't mean you need to supplement across the board. I'd always recommend eating a healthy diet composed of foods rich in vitamins such as the B's. Always better than pill-based-supplements when possible.

Some of us are B-deficient (b12, D, or iron), and we can get blood tests to see if that's our case. In that situation, you might need food and supplements (whether oral or IV) can be useful. I wouldn;t over supplement unless there's reason to.

At the very least you should get your blood levels of vitamin D checked. Google 'vitamin D IBD' and you will find dozens of studies indicating how helpful it is. More and more doctors are making this a standard routine. The optimum range is 40-60 ng/ml with over 100 ng/ml flirting with overdose. If you are like most of us then you will find that you are deficient.

Many IBDers are deficient in folic acid and zinc so it wouldn't hurt to get your blood levels tested. Taking a daily multivite probably wouldn't hurt. There isn't much danger overdosing B vitamins since your body will excrete the excess.