The most reliable sign that a baby is eating enough is consistent weight gain over time, according to the Mayo Clinic. A baby who is getting sufficient food also typically acts satisfied after feedings, has regular bowel movements and produces at least six wet diapers a day.
Most babies are weighed three to five days after birth and again within 72 hours after leaving the hospital to assess growth, according to KidsHealth. At these initial appointments, the doctor and mother can address any complications that might be interfering with proper feeding and infant growth. Babies often lose weight immediately after birth, but steady weight gain commences after this initial loss and the baby typically reaches or surpasses his initial birth weight after one or two weeks, explains the Mayo Clinic.
Newborn babies tend to consume small amounts of breast milk or formula frequently, but as the baby grows, feedings become less frequent and the infant takes in more milk per feeding, according to KidsHealth.
Signs that a baby might not be getting enough to eat include consistent fussiness after feedings, excessive sleepiness without any alert and active periods between naps, the presence of urine that is dark yellow or orange, and dry or hard stools, states the Mayo Clinic.