No personal experience but I had read Geezy and Bob's experiences sometime back. My son's best friend has had colitis issues since he was about 12-13. He has been in and out of hospitals throughout middle and high school. He has been to the point where a colostomy bag was looking like the next step. At 29 he recently had a really bad bout that left him hospitalized for a couple-three days. I didn't preach carnivore to him but I did tell him if he didn't do all out carnivore to cut out everything processed, fast foods, soft drinks, sugary type foods, eat mostly meat and do the fruits and vegetables sparingly. He says he feels better after a month or so and hadn't had any issues. I think, one it takes time for it to work, but it also takes time to see if it is working as the issues can sort of come and go. Good luck, Thoughts and prayers for your kid and your family. Tough deal for most anyone, even more so for a 12-year-old. Scott