I know I certainly feel a lot better when I have lots of veggies. I remember reading about one doc who said he could dramatically improve many kinds of intestinal disorder (e.g. celiac, IBS, chrohns), simply with a regimen of eating nothing but a plate full of greens every morning. Apparently this works wonders for gradually detoxing the bowel, and it certainly seems to have helped me in the past.
I also speculate that the sometimes hard-to-chew fibrous parts in green beans, etc might act as little scrubbing brushes for the intestine, perhaps wiping any candida away, which might otherwise cling on for dear life!