Infant feeding is the practice of feeding children who are below two years of age. The World Health Organization recommends that infants be exclusively breastfed for the first 6 months of life, followed by continued breastfeeding and gradual introduction of complementary foods. Breastfeeding is beneficial for both the mother and the infant. Breast milk is safe, sterile, and contains antibodies that protect infants against many childhood illnesses. In the US, infants who are not breastfed have a 21% higher risk of post-neonatal infant mortality. It is recommended that mothers who cannot breastfeed exclusively feed their infants with breast milk for at least four months before introducing complementary foods. Infant formula cannot be an absolute substitute for human breast milk, and the use of infant formula must be the last option to feed infants if mothers cannot breastfeed. Although breast milk continues to be an important source of nutrition for growing infants, at six months and beyond breast milk becomes insufficient to provide all the nutrient needs of infants. Therefore, infants must be introduced to complementary foods in addition to breast milk. Complementary foods should provide sufficient energy, protein, essential fats, oils, and particularly, micronutrients to meet the nutritional needs of infants.