Can following formula-feeding recommendations still result in infants who are overweight or have obesity?

Abstract

Background: Studies show that by 3 months, over half of US infants receive formula, and guidelines play a key role in formula feeding. The question then is, what might happen if caregivers follow guidelines and, more specifically, are there situations where following guidelines can result in infants who are overweight/have obesity?

Methods: We used our "Virtual Infant" agent-based model representing infant-caregiver pairs that allowed caregivers to feed infants each day according to guidelines put forth by Johns Hopkins Medicine (JHM), Children's Hospital of Philadelphia (CHOP), Children's Hospital of the King's Daughters (CHKD), and Women, Infants, and Children (WIC). The model simulated the resulting development of the infants from birth to 6 months. The two sets of guidelines vary in their recommendations, and do not provide studies that support amounts at given ages.

Results: Simulations identified several scenarios where caregivers followed JHM/CHOP/CHKD and WIC guidelines, but infants still became overweight/with obesity by 6 months. For JHM/CHOP/CHKD guidelines, this occurred even when caregivers adjusted feeding based on infant's weight. For WIC guidelines, when caregivers adjusted formula amounts, infants maintained healthy weight.

Conclusions: WIC guidelines may be a good starting point for caregivers who adjust as their infant grows, but the minimum amounts for JHM/CHKD/CHOP recommendations may be too high.

Impact: Our virtual infant simulation study answers the question: can caregivers follow current formula-feeding guidelines and still end up with an infant who is overweight or has obesity? Our study identified several situations in which unhealthy weight gain and/or weight loss could result from following established formula-feeding recommendations. Our study also suggests that the minimum recommended amount of daily formula feeding should be lower for JHM/CHOP/CHKD guidelines to give caregivers more flexibility in adjusting daily feeding levels in response to infant weight. WIC guidelines may be a good starting point for caregivers who adjust as their infant grows. In order to understand how to adjust guidelines, we can use computational simulation models, which serve as "virtual laboratories" to help overcome the logistical and ethical issues of clinical trials.

Figure 1.. Validation of Simulation Model.

This figures compares outputs from the Virtual Infant model when infants were fed calories to meet required energy needs derived from Butte (24) (dotted line) to real world data from WHO reference curve (solid line).

Figure 2.. Assessing impact of formula-feeding recommendations on infant BMI for 6 Months, Exclusive Formula-feeding.

Panel A: Food consumption based on Children’s Hospital of Philadelphia (CHOP)/Johns Hopkins Medicine (JHM)/Children’s Hospital of the King’s Daughters (CHKD) recommendations in female infants. Panel B: Food consumption based on Children’s Hospital of Philadelphia (CHOP)/Johns Hopkins Medicine (JHM)/Children’s Hospital of the King’s Daughters (CHKD) recommendations in male infants. Panel C: Food consumption based on Women Infants and Children (WIC) in female infants. Panel D: Food consumption based on Women Infants and Children (WIC) in male infants. Two-dashed lines (– – – –) represent virtual caregivers adjusting to the infants’ weight trajectory by feeding in the lower or upper quartile of feeding amounts in response to significant weight gain or loss, respectively. Solid lines (——) represent virtual caregivers adjusting to infants’ weight trajectory by feeding in the lower or upper half of feeding amounts in response to significant weight gain or loss, respectively. Dotted lines (·······) represent virtual caregivers feeding only within the bottom quartile of feeding amounts. Dashed lines (– – –) represent virtual caregivers feeding within the full range of feeding amounts with no adjustment responding to infant weight trajectories.