Although scurvy is seldom seen in breast-fed babies it is believed that an infant who is nursing at the breast of a woman whose diet is lacking or deficient in fresh milk, oranges and leafy vegetables will suffer a certain degree of starvation and thus be sickly and susceptible to infection without actually having scurvy. The significance to you, of this complicated and enormously important question of nutrition may be summed up as follows: 1. There are five recognized diseases resulting from faulty nutrition, which may be either prevented or cured by a diet which contains the protective substances, called vitamines, which are now regarded as essential to normal growth, development and well-being. 2. These essential substances are not necessarily provided in adequate amounts by a diet that is satisfactory in bulk or in its balance of fats, carbohydrates, proteins, salts and water or that yields the requisite number of calories. The familiar diet of meat, potatoes, peas, beans, bread, pie and coffee is so far from providing complete nourishment that those who are limited to it are in a state of partial starvation. 3. Although the breast tissues are capable of converting into milk certain substances which they extract from the blood, they cannot create the protective substances which we have been considering. They can merely excrete these substances if they are contained in the mother’s diet. The absence, or shortage of these food essentials in the mother’s diet, and therefore in her milk, may result in rickets or other malnourished conditions in the baby, or in a degree of faulty nutrition which is not marked enough to be diagnosed, but enough to keep him frail; enough to give him the poor start that is so likely to put him, ultimately, in the class of those adults who are more or less unfit, though not actually ill. 4. The great protective foods are milk and leafy vegetables and any diet which is poor in these is incapable of nourishing satisfactorily. By =milk= we mean fresh milk, first and foremost and also cream, butter, buttermilk, cream soups and sauces, custards, ice-cream and all dishes and beverages made of milk. By =leafy vegetables= we mean lettuce, romaine, endive, cress, celery, cabbage, spinach, onions, string beans, asparagus, cauliflower, Brussels sprouts, artichokes, beet greens, dandelions, turnip tops and the like. Other foods which are rich in protective substances are fresh fruit, egg-yolks and glandular organs, as liver and sweetbreads.