Switching to a tummy friendly formula can help. If a baby is born lactose intolerant, it’s usually discovered within the first day or two after birth. It’s extremely rare that babies are born lactose intolerant. Lactose intolerance is apparent shortly after birth. This major energy source may play roles in calcium absorption and promoting growth of healthy bacteria in the gut. People can forget that lactose is the primary carbohydrate in breast milk, accounting for 40% of its calories. In reality, it’s probably not lactose intolerance. Tummy issues are common at this age, and some moms perceive them as lactose sensitivity or intolerance. When your baby has tummy discomfort, it’s stressful for both of you. But lactose intolerance is probably not the cause. Many babies have tummy discomfort during their first year. Enfamil A+ Gentlease ® can help you and your baby feel calm and comfortable during feeding time and after.