This is a very balanced scientifical review from the American Dietary Association. Lots of references from technical literature I strongly reccomend its reading. If a physician says vegetarian diets are not advised, he or she should be referenced to the ADA review. It is stressed that the vegetarians, especially so the vegans, should be made aware of the potential issues deriving from their diet, providing adequate solutions. In the case of the B12 vitamins, the only advised solution for vegans is supplements or fortified foods, whereas in lacto-ovo-vegetarians the only issue is if an adequate amount of foods containing B12 is consumed.
http://www.vrg.org/nutrition/2009_ADA_position_paper.pdfIt is the position of the American Dietetic
Association that appropriately
planned vegetarian diets, including
total vegetarian or vegan diets, are
healthful, nutritionally adequate, and
may provide health benefits in the prevention
and treatment of certain diseases.
Well-planned vegetarian diets
are appropriate for individuals during
all stages of the lifecycle, including
pregnancy, lactation, infancy, childhood,
and adolescence, and for athletes.
