List of diseases that include unintentional weight loss as a symptom. Any major, well-known medical conditions associated with unintentional weight loss are included below, listed alphabetically with photos when available. Any maladies, sicknesses or illnesses with unintentional weight loss as a symptom can be seen below. For any real, further diagnosis of something you feel you might have, please consult a doctor. This list includes information about each disease, such as what risks are associated with it. Illnesses on this list include Crohn's disease and Peptic ulcer.This list answers the questions, "What risks are associated with unintentional weight loss?" and "What disease can I have if I have unintentional weight loss?"