Can diverticulitis cause weight loss?

Yes, because: Of the general illness of infection and limited oral intake during treatment. However, if weight loss persists, it could be from occult cancer, so it is best to consult with a GI specialist.

I guess but...: any time you are ill, especially if you are bloated or nauseous you can lose weight . But if the weight loss has been going on even when you do NOT have an active attack you need to look for another cause. Many bad diseases (cancer) can cause unexplained weight loss

It can: The pain and inflammation of this condition which affects the colon can cause weight loss. I would be concerned about cancer in this case also. Please be sure your doctor has ruled out cancer of the colon. It would be rare in someone as young as you, but it is not unheard of. If your doctor does not seem interested in checking for cancer, get another opinion. Better safe than sorry.

It can: It can do so secondarily. The disease itself doesn't cause weight loss, but it can make you feel sick and weak and decrease your appetite, which can consequently cause weight loss.