Park Hyojun, Reither Eric N
Department of Sociology and Anthropology, Utah State University, Logan, Utah, United States of America.
PLoS One. 2025 May 29;20(5):e0323967. doi: 10.1371/journal.pone.0323967. eCollection 2025.
Empirical evidence with respect to the protective effect of breastfeeding on childhood obesity remains inconclusive, and studies on sex-specific associations are sparse. We investigated whether (H1) longer breastfeeding duration reduces the risk of entry into elevated body mass (EBM); and (H2) longer breastfeeding duration increases the likelihood of exit from EBM. Using the Early Childhood Longitudinal Study, Birth Cohort (ECLS-B), our sample comprised 10,550 mother-child pairs after excluding 100 non-biological pairs. The ECLS-B assessed children from 9 months of age through kindergarten, spanning infancy through 7 years of age. We used two transitions in weight status (i.e., entry to EBM and exit from EBM) as outcome variables. The main predictor was breastfeeding duration (i.e., never breastfed, up to 2 months, 3 to 7 months, and 8 months or longer). Multilevel discrete-time models for recurrent transitions were employed to examine bidirectional changes in weight status. Among girls, breastfeeding for 8 months or longer reduced the risk of transitioning into overweight (adjusted Hazard Ratio (AHR): 0.76, 95% CI: 0.64, 0.89) or obesity (AHR: 0.66, 95% CI: 0.53, 0.82). Breastfeeding duration increased the likelihood of exiting EBM in a dose-response fashion among girls. Among boys, breastfeeding for 3 to 7 months was associated with preventing overweight (AHR: 0.79, 95% CI: 0.67, 0.92) or obesity (AHR: 0.82, 95% CI: 0.68, 0.98), but it did not help overcome EBM, regardless of breastfeeding duration. Breastfeeding duration helped to prevent EBM or overcome it, but these effects varied by the child's sex. Further research should elucidate how the benefits of breastfeeding may differ for boys and girls, and explore the potential need for sex-specific public health policies.
关于母乳喂养对儿童肥胖的保护作用的实证证据仍然不明确，而且关于性别特异性关联的研究也很少。我们调查了：（H1）更长的母乳喂养持续时间是否会降低进入高体重（EBM）状态的风险；以及（H2）更长的母乳喂养持续时间是否会增加从EBM状态恢复的可能性。利用儿童早期纵向研究出生队列（ECLS - B），在排除100对非亲生母子对后，我们的样本包括10550对母子对。ECLS - B对从9个月大到幼儿园阶段的儿童进行评估，涵盖婴儿期到7岁。我们将体重状态的两个转变（即进入EBM状态和从EBM状态恢复）作为结果变量。主要预测因素是母乳喂养持续时间（即从未母乳喂养、长达2个月、3至7个月以及8个月或更长时间）。采用多水平离散时间模型来研究体重状态的双向变化。在女孩中，母乳喂养8个月或更长时间可降低转变为超重（调整后风险比（AHR）：0.76，95%置信区间：0.64，0.89）或肥胖（AHR：0.66，95%置信区间：0.53，0.82）的风险。母乳喂养持续时间在女孩中以剂量反应方式增加了从EBM状态恢复的可能性。在男孩中，母乳喂养3至7个月与预防超重（AHR：0.79，95%置信区间：0.67，0.92）或肥胖（AHR：0.82，95%置信区间：0.68，0.98）相关，但无论母乳喂养持续时间如何，都无助于克服EBM状态。母乳喂养持续时间有助于预防EBM状态或克服该状态，但这些影响因儿童性别而异。进一步的研究应阐明母乳喂养的益处对男孩和女孩可能有何不同，并探索针对性别的公共卫生政策的潜在需求。
