Summary: In children aged 2–6 with overweight or obesity, a parent-based lifestyle intervention reduced BMI, BMI z-score, and energy/macronutrient intake more than standard care; salivary AMY1 gene copy number related to baseline carbohydrate intake and adiposity but did not predict who responded.
PICO Summary
| Element | Detail |
|---|---|
| Population | 90 children aged 2–6 with overweight or obesity (9-month intervention). |
| Intervention | Parent-based lifestyle support targeting nutrition and BMI through behaviour change. |
| Comparison | Standard care (general advice without structured parental involvement). |
| Outcome | Intervention reduced BMI, BMI z-score, and energy/macronutrient intake more than control. Higher AMY1 copy number correlated with higher baseline carbohydrate intake and BMI z-score and greater post-intervention PUFA reduction, but showed no association with BMI z-score change. |
Expert Commentary
There are really two studies bundled here, and they deserve different verdicts. The lifestyle arm is the solid part: parent-based behaviour change beat standard advice in preschoolers, which is exactly what paediatric obesity guidance already tells me to do, so that finding reassures rather than surprises. The AMY1 genetics is the seductive part, and I am deliberately cool on it. The honest result is that copy number tracked with baseline carbohydrate intake and adiposity but did not predict who actually responded to the intervention, which is the only thing that would make it clinically useful. That fits the wider literature, where early excitement about AMY1 and obesity has been tempered by larger studies and by how notoriously hard the copy number is to measure. Gene-by-intervention analyses like this are also usually underpowered to trust a null. Can I use this with my patients? The lifestyle message, yes, immediately; the genetics, no, AMY1 testing has no place in selecting or tailoring treatment today. I would treat the genotype angle as hypothesis-generating and keep my focus on engaging parents and tracking BMI z-score.
References
Monserrat-Mesquida M, Bouzas C, Cardoso H, et al. Salivary amylase gene copy number relates with BMI z-score and with response to lifestyle intervention for children with overweight and obesity. Int J Mol Sci. 2025;26(18):9059. doi:10.3390/ijms26189059