This statement proposes recommendations toward increasing the practice of breast feeding. Specific recommendations made for standards of infant formulas as to calorie, protein, fat, vitamin, and mineral levels apply to both milk-based and milk-substitute infant formulas. Such formulas, when used in place of breast-feeding, must supply most or all of the nutrients infants require during the first weeks or months of life. The minimum levels of nutrients per 100 kcal recommended for formulas provide good growth and development in healthy, full-term infants; distinct hazards may be encountered at levels below these. However, no significant advantage is to be gained by providing levels in excess of these minima in normal infants. Recommendations for maximum levels are made only where quantities in excess lead to toxicity; generally, levels near the minima recommended are most desirable because they are the most likely to reflect the composition of human milk, and the least likely to result in any undesirable nutrient to nutrient interaction. The recommendations also can be used as reference standards for formulas for special dietary uses of "medical" formulas. The Committee recommends that "medical" formulas be classified by FDA into a special group under the paragraph dealing with infant formulas.