There is a lot of evidence that vegan diet isn't so healthy as the mass media presents. It's true that we as people eat too much meat and it is also true that some meat is toxic, but not eating meat at all has its own risks. People who eat fish and eggs on a weekly basis and from time to time pork or chicken are in average healthier than vegans (if they let out fast food, chips, sweets etc.). Moderation is the key to healthy life and I think that applies to literally everything. :)