RD, LDN, CBS
Certified in Maternal and Infant Nutrition from Cornell, Angela’s mission is to help people reach their wellness goals. She also helps run a program that teaches pregnant women about how a healthy lifestyle optimizes prenatal and postnatal care.
The First Month
Gassiness and spitting up is normal in newborns, and while there are individual variations, for the most part it’s due to an immature digestive system. It’s normal for babies to strain and turn a little red when having a bowel movement, even when passing watery breast milk stool.
Constipation (infrequent and hard bowel movements) is common in formula-fed babies in the first month or so, and is usually due to the large amount of iron in most formulas. It typically resolves after 4-6 weeks of age. Gently pulling and pushing baby’s legs in and out, bicycling her legs, and light belly massage can all help to get things moving. Speak with baby’s doctor if the constipation isn’t getting better or stools are bloody, or if you have any other concerns.
Beyond the First Month
Spit up and gassiness continue to be normal. Once solid foods are introduced, you will see further changes in baby’s bowel habits.
Red Flags that baby may not be tolerating their current formula:
Most of the time allergy or intolerance issues are due to the milk or soy proteins present in cow’s milk and soy-based formulas, although other ingredients could be the culprit. It’s rare for a baby to be lactose intolerant.
When to switch formulas
It’s always important to consult with baby’s pediatrician when you feel that you need to switch baby’s formula. If an allergy or significant intolerance is suspected, soy formula is often bypassed for a partially hydrolyzed formula or occasionally a different form (concentrate versus powder versus ready-to-feed) or brand. Severe allergies are dealt with using hypoallergenic formulas.
When transitioning your baby from one formula to another due to an allergy, intolerance, or medical condition, an immediate switch is usually recommended (as opposed to a slow transition). Confirm the appropriate formula transition timing and switch with your baby’s pediatrician.
In the absence of an allergy, intolerance or medical condition that would warrant switching formulas cold turkey, some parents choose to transition between formulas slowly.
If you decide on the slower course, use the guide below and transition to the next step every 1-2 days.
Assuming baby takes 4 oz of formula:
In the end, it’s important to recognize what’s normal and what’s a red flag with regard to baby’s digestion. Before considering a formula switch, double-check to make sure you are preparing the formula properly and that you are following baby’s hunger and fullness cues. Sometimes encouraging a full baby to finish their bottle can cause baby to be gassy or to spit up quite a bit. Always work with baby’s doctor to find the best formula for your little one!
“Choosing an Infant Formula.” American Academy of Pediatrics. Date accessed 25 July 2018. “Infant Food and Feeding.” American Academy of Pediatrics. Date accessed 25 July 2018. Mohrbacher IBCLC, FILCA Nancy. “Breastfeeding Answers Made Simple.” 2010.