Vitamin B is not absorbed in the colon, it's absorbed in the terminal ileum. I have my vitamin B levels checked every year with my CBC and have not lacked vitamin B in the past six years. Vitamin K is abosrbed in the colon. Best to ask your GI about the need to supplement/replace that.
dx proctitis in 1987
dx UC in 1991, was stable until 1998
1998 started prednisone, asacol, pentasa, nortriptylene, ativan, 6MP, rowasa enemas and suppositories, hydrocortisone enemas, tried the SCD diet, being a vegetarian, omega 3s, flax, pranic healing, yoga, acupuncture, probiotics
2000 lost all my B-12 stores and became anemic
2001 opted for j-pouch surgery- now living life med-free