Study · Nutrients · 2024Conflicts declared

Lactose content and nutrient profile of infant formulas

What it found

In 88 US infant formulas, those with less lactose had more added sugar, protein, and a higher glycemic index.

This was a database analysis, not a study in infants.

What they found

Added sugar

Lactose-free formulas had more added sugar per 100 g than lactose-reduced or 100% lactose formulas. For each 1 g decrease in lactose per 100 g, added sugar rose by 19%.

Glycemic index

Formulas with less lactose had a higher glycemic index. For each 1 g decrease in lactose per 100 g, glycemic index rose by 10.1%.

Protein

Lower lactose formulas had more protein. For each 1 g decrease in lactose per 100 g, protein rose by 5%.

Polyunsaturated fats

Polyunsaturated fatty acids, including omega-3 and omega-6, increased as lactose decreased. For each 1 g decrease in lactose per 100 g, these fats rose by 2%.

Saturated fat

Saturated fatty acids were highest in the 100% lactose formulas.

What the authors conclude

“Lactose-reduced and lactose-free formulas had higher protein, added sugars, GI, and certain PUFAs compared to lactose-based formulas.”
Mokhtari P, Schmidt KA, Babaei M, Goran MI, 2024

Also in their conclusions

  • They say that lactose-reduced and lactose-free formulas had higher protein, added sugars, glycemic index, and certain polyunsaturated fatty acids compared to lactose-based formulas.
  • They advise that these changes could have significant implications for infant growth, metabolic responses, and long-term health.
  • They call for further research on the long-term consequences of lactose replacement to guide infant formula composition.

How it was done

The authors wanted to see whether the nutrient profile of infant formulas differs by lactose content, since many healthy infants may be given lactose-reduced or lactose-free formula without a medical need.

They used a nutrient database to compare 58 nutrients and glycemic index across 88 infant formulas sold in the US, grouped as lactose-free, lactose-reduced, or 100% lactose.

What it can’t tell you

  • This study looked at nutrient labels in a database, not at infants drinking the formulas.
  • It cannot show what health effects these nutrient differences have in real babies.

The paper

Title
Altered Nutrient Composition of Lactose-Reduced Infant Formula
Type
Study
Summarised from
Full text
Cite
Mokhtari P, Schmidt KA, Babaei M, Goran MI (2024). Altered Nutrient Composition of Lactose-Reduced Infant Formula. Nutrients. doi:10.3390/nu16020276Free full textPubMed 38257168DOI

Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error