PROJECT SUMMARY/ABSTRACT
Obesity affects 1 in 5 children and adolescents in the United States and prevalence of severe obesity is
worsening. Despite advances in treatment for obesity, primary prevention is essential to prevent morbidity and
early death. Infants who gain weight rapidly have over 4 times higher odds of developing obesity as a child or
adult, and rapid weight gain during infancy also explains a large percentage of the entrenched and worsening
racial and ethnic disparities in childhood obesity and subsequent cardiometabolic disease. Infants who are
predominantly bottle-fed are at higher risk for excessive infancy weight gain and childhood obesity, yet we do
not have effective interventions to reduce excessive weight gain among infants who are bottle-fed. Our
preliminary work suggest that two novel intervention strategies are feasible and may reduce excessive infancy
weight gain: reducing bottle size; and increasing bottle opacity. Both smaller size and increased opacity
attenuate the visual cues that may encourage overfeeding of bottle-fed infants and overriding infants’ hunger
and satiation cues. Our past observational work shows the size of the infant bottle is positively associated with
total formula fed, weight-for-age, and weight-for-length from 2 months through 12 months of life. Our past
experimental work shows that smaller bottles are a feasible intervention from the primary care setting. We
have also shown that caregivers using opaque bottles showed greater sensitivity to their infant’s hunger and
satiation cues and fed their infants less than when using clear bottles. Opaque bottles were acceptable and
feasible in a community-based intervention over 3 months. We aim to test the independent and joint efficacy of
these two intervention components among exclusively bottle-fed infants in a randomized, full factorial clinical
trial. We hypothesize that smaller and opaque bottles reduce conditional weight gain, decrease volume per
feed, and improve caregiver sensitivity to infant hunger and satiation cues. Our objective is to understand the
independent and joint efficacy of reduced bottle size and increased bottle opacity and to collect additional
feasibility and acceptability data in order to facilitate rapid translation and implementation of optimized bottle
feeding strategies. We plan to achieve our objectives by (1) assessing the independent and joint efficacy of
reducing bottle size and increasing bottle opacity to reduce excessive weight gain from birth to four months of
infant life, (2) determine the effects of reducing bottle size and increasing bottle opacity on changes in volume
per feed and on caregiver-infant dyad feeding interactions through video-recorded feeding observations, and
(3) quantify and describe factors associated with eligibility, enrollment, and adherence to bottle design
interventions. To achieve these aims, we have assembled a team of experts in obesity, primary care-based
clinical interventions, infant growth, caregiver-infant dyadic feeding behaviors, factorial designs, and
biostatistics. The results from this novel intervention strategy will be used to design a large, multicenter clinical
trial of a comprehensive bottle-feeding strategy to reduce the incidence of obesity in early childhood.