As you read along, you'll find out that most health conditions developed by vegans are related to vitamin B12 deficiency. Without the familiar sources of vitamin B12, certain bodily functions can be disrupted, leading to anemia, gastritis, stroke, Crohn's disease, and Celiac disease.

Beer and Wine Isinglass, a gelatin-based substance derived from fish, is used as a clarifying agent in some beer and wine. Other non-vegan ingredients sometimes used are casein (from milk) and egg whites.

Vegan diets have also been shown to help in the treatment of type 2 diabetes by lowering total and LDL cholesterol and by controlling lipid levels, for example by reducing triglycerides, a type of fat that is also associated with a greater risk of heart disease (Jenkins et al.