It's a B vitamin that your body needs to make healthy new cells. In women, it also protects against birth defects of the baby's spine or brain. And it can lower your risk of colon cancer, which is higher in people with ulcerative colitis.
When you have UC you may find it hard to eat folate-rich dark leafy vegetables and may end up with low levels of the vitamin. Those levels can go even lower if you need certain medications. Ask your doctor if you should be taking a folic acid supplement.