"It is the position of The American Dietetic Association that vegetarian diets are healthful and nutritionally adequate when appropriately planned."
Position of the American Dietetic Association: Vegetarian Diets - technical support paper", Suzanne Havala, R.D. and Johanna Dwyer, D.SC., R.D. Journal of the American Dietetic Association, March, 1988, Volume 88, Number 3, pp. 352-355.