The vegetarians who eat milk and eggs are not vegetarians, strictly speaking. No diet including milk and eggs is a deficient diet, provided always that enough of them is taken. Meat and fish need never be eaten and perfect health may still be maintained.

But the problem is a difficult one with the true vegetarian who would eat neither milk nor eggs. From what has already been said, we must consider milk as the most important of our foods. It is the protective food which makes up for various deficiencies in other foods. To make up such deficiencies without the use of milk, particularly where meat and fish are also excluded, is not only difficult but dangerous. Theoretically, there is no reason why a complete diet cannot be formed from a mixture of cereals, vegetables and fruit. If chemical and physiological analysis had proceeded far enough, we might have been able to select all the necessities from even such a restricted diet.

But though we know much more to-day than we did a generation ago, the science of nutrition is still far from complete.