To ensure a good breast milk supply, drink enough fluids to satisfy your thirst and prevent dehydration. You need at least 8 to 12 cups of fluids daily — more if you feel thirsty. Sip on a glass of water, milk or juice while you are nursing your baby. Milk and juice also supply some of the extra nutrients needed for breastfeeding. Limit the amount of caffeine beverages such as colas, teas and coffees to two servings or less each day. Too much caffeine may cause your baby to become active and lose sleep.