Most infant formulas in the U.S. contain mostly added sugars instead of natural lactose, which experts say can harm early development, a new report from the University of Kansas shows.

“Infants may consume upwards of 60 grams of added sugars per day, or the equivalent of two soft drinks per day if they are entirely formula-fed,” researchers say in the study, published yesterday [Feb. 24, 2025] in the Journal of Food Composition and Analysis. 

The findings reveal “the staggering extent” to which sugar-laden U.S. formulas undermine federal healthy diet recommendations for infants—and cannot be easily avoided, they say.

“[Most] of the formulas that parents and caregivers feed their infants likely present a substantial risk to their infant’s health and development. Ultimately, caregivers and infants in the US deserve a formula market that promotes healthy infant development and does not promote early obesity risk.”

Added sugars provide energy but lack nutritional value, boosting the odds of rapid infant weight gain that can eventually lead to obesity, type 2 diabetes, cardiovascular disease, and other health problems. They may also make babies develop a stronger preference for sweet foods, increasing the risk of overeating and obesity later in life. And they do not support beneficial gut bacteria as well as lactose.

In contrast, lactose, which is naturally found in breast milk, cow and goat milk, is perfectly designed to support an infant’s nutrition, immune system, and gut health, researchers say. Because lactose digests slowly, it doesn’t cause the sharp spike in blood sugar that can set the stage for long-term health problems. It also satiates hunger and helps the body absorb minerals that are important for bone health.

Dr. David Ludwig, an endocrinologist and researcher at Boston Children’s Hospital who conducted some of the original studies linking sugar-sweetened beverages and fast food to obesity, calls infant formula spiked with added sugars a “metabolic nightmare for infants.”

“You lose the beneficial effects of what lactose does, and you get the harmful effects of what these fast-digesting sugars do,” Ludwig says. “Unless we’re talking about the very rare child who can’t take lactose, that should be the dominant carbohydrate.”

Out of 73 formulas available in the U.S. in 2022, the vast majority of which were for infants up to 12 months old, the researchers found only five contained mainly naturally occurring lactose—and those are no longer available in this country. It is unknown whether any formulas on the current U.S. market contain primarily naturally occurring lactose, they say.

The study also shows the quality and type of sugars in infant formulas varied by formula. Gentle (with marketing claims such as “gentle,” “soothe,” “sensitive,” or “acid reflux”) and lactose-free formulas contain less sugar than standard formulas but much more starch, the study shows.

“Our findings highlight a major problem with the infant formula supply,” says lead author Audrey Rips-Goodwin, who headed the analysis of data from the Nutrition Data System for Research for KU’s Health Behavior and Technology Lab. “Our infant formula market totally contradicts what experts in infant health recommend.”

Children under 2 years should not be given any foods or beverages with added sugars, since they need nutrient-rich diets and are developing taste preferences, according to the American Academy of Pediatrics and the Dietary Guidelines for Americans (2020–2025). Yet with few formula options free of added sugars, the researchers say parents and caregivers who can’t breastfeed or access breast milk face tough choices in terms of finding a nutritionally suitable formula due to lax government regulations.

Unlike adult food products, US regulations do not require that added sugars be reported on the nutrition label of infant formulas (only total carbohydrates). The FDA specifies 30 nutrients that must be included in infant formulas but does not regulate the types of carbohydrates or require their clear labeling. That means formula manufacturers can use any type of carbohydrate, including starches or added sugars such as corn syrup solids, fructose, and glucose.

“Consumers are blinded to the fact that added sugars may be present in infant formulas, and in what quantities,” the researchers say. “As a result, parents and guardians may unknowingly feed their infants formula that contains substantial quantities of added sugars.”

The study builds on others that revealed the high sugar content of infant formula. It also comes less than a year after news reports that two of Nestlé’s leading baby-food brands, promoted as healthy in Africa, Asia, and Latin America, contain high levels of added sugar.

To promote healthy development, the researchers say efforts should focus on requiring formula companies to produce products that contain naturally occurring lactose as the only sugar. The amount of lactose present in infant formula should also reflect that of human milk.

At the same time, societal barriers to breastfeeding, including a lack of parental leave and affordable early child care, should be removed, the researchers add.

“[The] focus on an individual-level solution (breastfeeding promotion to women and caregivers) is not well matched to addressing the systemic nature of the problem and places an unfair burden on women and families who are expected to navigate this systemic issue,” Rips-Goodwin says.

Senior author Tera Fazzino agrees.

“Even though breastfeeding is promoted as the best option, the lack of support makes it hard to do exclusively,” says Fazzino, associate director of the Cofrin Logan Center for Addiction Research & Treatment at KU’s Life Span Institute. “Most parents end up using formula, either as a supplement or completely. But our findings suggest that formula itself may pose a serious risk to infant health.”

Reference

Rips-Goodwin AR, Jun D, Griebel-Thompson A, Kong KL, Fazzino TL. US infant formulas contain primarily added sugars: An analysis of the infant formulas on the US market. Journal of Food Composition and Analysis. Published online February 2025:107369. doi:10.1016/j.jfca.2025.107369