I am sure there are those out there that can navigate strict veganism - but that has not been my experience with vegans. The key is - proteins in sufficient quantity. Most strict vegans I have dealt with over the years find it almost impossible to meet their protein needs over the long haul by diet alone - especially if they are also into some kind of extreme exercise routine as with runners. They need supplementation to keep up with the demand. Very few people that I have treated make it past a 20 to 25 year practice with strict vegan diets without a very similar wasting of muscle and bone mass. Research shows that vegans are at higher risk for bone fractures than people that consume animal products and I can verify that claim by my own patients. They seem to be much more prone to severe shattering type of fractures than their non vegan counterparts - and at a much younger age.

Vegans must monitor the deficiencies known to come with the lack of animal products in the diet - and I mean good organic animal products. There can be several mineral deficiencies as well as things such as CLA and B12. Carnitine and taurine are two non essential amino acids that vegans can have deficient states because of a possible inability of the body to make adequate amounts or a lack of the precursor amino acids, such as cysteine, in order to make other non essential amino acids. They usually need supplementation. In my experience as a clinician, vegans that do consume some kind of good clean animal products occasionally do seem to fair better over the years.