veganism: I've heard and read omnivores say that they cant be vegan or vegetarian due to a certain disease or food allergy... Is there any disease or food allergy/allergies (some have more than one) that makes vegetarianism or veganism impossible? I understand it may make it more difficult, but is there any disease or food allergy that makes it downright impossible that they absolutely must have meat and/or dairy?|||No. That's the most ridiculous thing I've ever heard. An allergy or disease that forces them to eat meat, fish, eggs & dairy? Allergies usually prevent someone from eating a certain thing, not force the person to include specific foods in their diets. As for diseases, a certain disease may mean you need to consume more, for example, calcium, because of a bone disease. However, as long as you can get your calcium from non-dairy sources, and still get the amounts you need (depending on your disease), you will be perfectly fine. People who say they have an allergy or disease that forces them to eat fish, meat, dairy or eggs, are either terribly naive, simply not willing to put in the effort, or bullsh!tting you. For every vitamin and nutrient, there is more than one source to obtain it from. Sure, it might not be the most apetizing, splendid, tasteful thing, but it is a source of a certain vitamin or nutrient. If veganism really means that much to someone, I think you'd put in the effort and remember your moral reasons for going vegan when you have to eat the distateful food. Bottom line? You're never stuck with simply getting your ___x___ from source y.|||no anyone can be vegan with a blanced diet