First, you’ll want to consider the type of formula that your baby needs. Most infants drink a cow’s milk-based baby formulas that have been modified to be more digestible and safe for little ones. This is the most common type of baby formula, according to the AAP.
However, there are other types too: Partially hydrolyzed baby formulas have been partially digested, which can help babies who deal with colic or gas. Extensively hydrolyzed baby formula, also called predigested formula, contains broken-down milk proteins, making them easier for babies to digest; these are well-tolerated by most babies who are allergic to cow’s milk. Soy-based formula may be an option for your baby if she is intolerant to galactose, but this condition is very rare, so only make this switch under your pediatrician’s guidance. And some babies may require special formulas, such as preemies or babies with specific diseases.
In addition to type, you can also review a formula’s ingredients. However, all infant formulas marketed in the U.S. must meet strict nutrition guidelines from the Food and Drug Administration (FDA), so while every formula is unique, you can rest easy knowing all the choices on the shelf are regulated.
“I always describe the different formulas kind of like Coke and Pepsi: They're pretty much the same, but a little different,” says Dr. Feeley.
Dr. Abelowitz agrees. “We always tell parents that, same as different Tylenols and Motrins and brands, when you have dozens, or these days, maybe even hundreds of different types of options, there almost isn't one that's superior to the other,” he says.
In addition to all the ingredients the FDA requires in a baby formula, several formulas on the market also contain a few extra ingredients that may help your infant grow and develop, like DHA (docosahexaenoic acid) and ARA (arachidonic acid).
You may also find that some formulas include prebiotics or probiotics, which are designed to support immune health. (A common example you’ll probably see on formula labels is 2'-FL HMO, aka 2′-fucosyllactose human milk oligosaccharides, which are found in breast milk.) While these generally don’t have much evidence to support their use, they’re also not thought to hurt, Dr. Feeley says. “This is part of formulas trying to mimic human milk as much as possible,” she explains.