Overweight and obese infants present lower cognitive and motor development scores than normal-weight peers.

Camargos et al. (2016) compared Bayley-III scores in overweight or obese infants with scores in normal-weight peers.

The team used a quasi-experimental design. All babies were 18-24 months old.

Heavier babies scored lower on both the thinking and the moving parts of the Bayley-III.

The gap was big enough to flag possible delays.

Mas et al. (2019) saw the same pattern, but in preterm infants who had too few calories. Both studies show Bayley-III dips when nutrition is off—too much or too little.

Howe et al. (2016) push the story further. They show that early Bayley scores, plus mom’s education, predict later IQ and motor skills in very low birth weight kids. This tells us the low scores Resende found may echo into preschool.

Akhtar et al. (2022) add a warning: only seven small studies test weight-loss programs for kids with intellectual disability. We can spot the risk early, yet we still lack ready-made treatments.

If you weigh and measure babies during assessment, add a quick Bayley-III screener when weight is high. A low score gives you an early heads-up to start motor or language goals before the gap widens. Pair this with parent coaching on healthy feeding routines—you do not need a special obesity protocol, just earlier, sharper ABA targets.