According to the document, infants have evolving nutritional needs from birth through their first year. At birth, they require milk through breastfeeding or formula. By 4 weeks, they can have orange juice or vitamin C supplements, and fluoridated water by 3 months. Cereals are introduced at 3 months to provide iron, B vitamins, and different tastes. Pureed foods like eggs, fruits, vegetables, and meats are gradually added between 4-7 months to supply necessary proteins, vitamins and minerals. By their second year, infants can eat chopped adult foods containing a variety of nutrients.