At 3 months of age, babies usually do not need to drink water because the water obtained through breast milk is sufficient to meet the needs of the body. After drinking extra water, it will affect the baby’s milk intake because the digestive juices will be diluted after drinking water, thus affecting the baby’s digestion and absorption function. There is also the phenomenon of occupancy, which causes a reduction in the baby’s breast milk intake, and this can lead to malnutrition in the long term. Only after 6 months of age or more, after the beginning of the addition of complementary foods baby to consider the appropriate increase in water, but the amount should also be controlled. The guidelines recommend not to exceed 200mL, that is, not to drink too much water. Otherwise, it will cause dilution of digestive juices, poor digestion, and reduced breast milk intake, which can lead to malnutrition.