Clinical evaluation of two different protein content formulas fed to full-term healthy infants: a randomized controlled trial

BMC Pediatr. 2018 Feb 13;18(1):59. doi: 10.1186/s12887-018-1046-6.


Background: A high early protein intake is associated with rapid postnatal weight gain and altered body composition. We aimed to evaluate the safety of a low-protein formula in healthy full-term infants.

Methods: A randomized controlled trial was conducted. A total of 118 infants were randomized to receive two different protein content formulas (formula A or formula B (protein content: 1.2 vs. 1.7 g/100 mL, respectively)) for the first 4 months of life. Anthropometry and body composition by air displacement plethysmography were assessed at enrolment and at two and 4 months. The reference group comprised 50 healthy, exclusively breastfed, full-term infants.

Results: Weight gain (g/day) throughout the study was similar between the formula groups (32.5 ± 6.1 vs. 32.8 ± 6.8) and in the reference group (30.4 ± 5.4). The formula groups showed similar body composition but a different fat-free mass content from breastfed infants at two and 4 months. However, the formula A group showed a fat-free mass increase more similar to that of the breastfed infants. The occurrence of gastrointestinal symptoms or adverse events was similar between the formula groups.

Conclusions: Feeding a low-protein content formula appears to be safe and to promote adequate growth, although determination of the long-term effect on body composition requires further study.

Trial registration: The present study was retrospectively registered in (trial number: NCT03035721 on January 18, 2017).

Keywords: Body composition; Full-term infants; Growth; Low-protein formula; Safety.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Body Composition*
  • Child Development*
  • Dietary Proteins*
  • Female
  • Follow-Up Studies
  • Humans
  • Infant
  • Infant Formula / chemistry*
  • Infant, Newborn
  • Male
  • Prospective Studies
  • Single-Blind Method
  • Weight Gain*


  • Dietary Proteins

Associated data