Characterization of infant energy balance to optimize early life growth

The National Institute of Diabetes and Digestive and Kidney Diseases awarded Pennington Biomedical Research Center $731,916 on August 10, 2026, under the Diabetes, Digestive, and Kidney Diseases Extramural Research program (CFDA 93.847) to conduct a prospective longitudinal study characterizing infant energy balance from one to twelve months of age.

The study will enroll 100 healthy infants and assess them at one, three, six, nine, and twelve months using gold-standard methods adapted for infants. Researchers will objectively measure energy intake using the intake-balance method and quantify free-living total daily energy expenditure, sedentary energy expenditure, and physical activity energy expenditure. Assessments will integrate physiological biomarkers (T3, leptin, epinephrine), behavioral factors (feeding patterns, milk type, timing of complementary foods, accelerometry), and developmental milestones to identify drivers of accelerated versus appropriate growth. The research addresses the gap in longitudinal energy balance phenotyping data; current infant energy intake reference standards rely on decades-old data and produce mean prediction errors of 16 percent, reaching up to 71 percent in some cases, leading to unintentional overfeeding during a critical window of metabolic programming in infants one to three months old.

Performance occurs in Baton Rouge, Louisiana, with a period of performance through April 30, 2031. Pennington Biomedical Research Center is a Louisiana State University-affiliated research institution.

Abstract

One in four U.S. Children enter kindergarten with overweight or obesity, yet the fundamental determinants of infant energy balance (i.e., the interplay of intake and expenditure) are poorly defined. Current reference standards for infant energy intake rely on decades-old and limited data. Our preliminary data demonstrates large errors (mean 16%, up to 71%) in predicted energy needs among 1-3-month-old infants, showing that such standards promote unintentional overfeeding during a critical window of metabolic programming. This highlights the lack of longitudinal energy balance phenotyping studies to understand the drivers of a more positive energy balance, thus, accelerated growth. Here we propose, characterization of infant energy balance to optimize early life growth, a first-of-its-kind prospective observational study healthy infants (n=100) longitudinally assessed from one to 12 months of age; at one, three, six, nine, and 12 months. Using gold-standard, rigorously adapted methods for infants, we will objectively assess energy intake (intake-balance method) and quantify free-living total daily energy expenditure (tdee), sedentary energy expenditure, and physical activity energy expenditure. We will combine these with other physiological measures including biomarkers T3, leptin, and epinephrine, behavioral factors (feeding patterns, milk type, timing of complementary foods, accelerometry) and developmental progression (gross motor milestones) to precisely phenotype infants and identify drivers of growth. The principal aims are to objectively assess components of energy balance throughout the first year of life and compare between those with accelerated and appropriate growth. This is novel because while we propose a prospective study design, we have opportunities to perform retrospective analyses at each three-month assessment to utilize point estimates along each of the three months to predict growth using newly identified drivers. This allows for identification of vulnerable periods for excess growth, such as specific ages or developmental milestones such as the introduction to complementary foods or periods of delayed gross motor achievements. This study will generate the first robust dataset on infant energy balance and its mechanistic underpinnings. By revealing physiological and behavioral drivers of early growth and updating imprecise energy standards, findings will directly inform strategies to prevent youth- onset obesity.