As a result, you may be thinking about changing his formula, or perhaps digestive issues like fussiness, gas and spitting up triggered the thought. No matter what, it’s best to speak with your doctor before switching your baby’s formula, while keeping these next few pointers in mind:
- Don’t worry about alternating or combining the new formula with the formula you’ve been using: Baby’s transition to the new formula can happen right away.
- Avoid mixing different formulas! Here’s why it’s not recommended: Formulas aren’t meant to be combined. Plus, if your baby experiences digestive issues, you won’t be able to identify the cause.
- Give your baby 3 to 5 days to get used to the new formula: It may take him some time to adapt. (Though he may even adjust right away. Yay!) While you’re transitioning, your baby may go through some other slight changes—mainly to his stool pattern, gas and how often he spits up. Don’t worry, though, this is normal!
Remember, you should consult with your baby's doctor before switching formulas, so you can always raise any other questions or concerns at that time.
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Choosing a feeding method can weigh on any parent’s mind—so here’s what you can consider when it comes to meeting your baby’s nutrition needs.

Why choose Nestlé® Good Start®?
GOOD START formulas are tummy friendly and easy to digest*. Designed with baby’s comfort in mind, only GOOD START formulas have comfort proteins, which are 100% whey proteins that have been partially broken down using our unique process for small tummies.
Whenever you may decide it’s time for formula, choose GOOD START PLUS. It’s our closest formula to breast milk and the only non-GMO** baby formula with Comfort Proteins™, Probiotics^.
Our Most Tummy Sensitive Formula
Designed to give sensitive tummies extra comfort, GOOD START SOOTHE is easy to digest* and has 30% less lactose compared to other GOOD START milk-based formulas. It is our most advanced formula that contains L. reuteri, a good bacteria that helps GOOD START SOOTHE give fussy babies what no other formula can.
Over 90% of parents who switched to GOOD START SOOTHE said their baby was less fussy after the first feed †,1.
* Like all infant formulas
† Infants were exclusively formula fed; Canadian formulation differs slightly from the GOOD START SOOTHE formula used in the study.
1 Czerkies L et al., 2019. Journal of Pediatric Health And Nutrition. 1(1):19-26.
**Ingredients not genetically engineered.
^Probiotics only in powder format.