Abstract：
The impact of milk on bone health in rural preschoolers is under-researched. This study, through a clinical trial and a meta-analysis, finds that milk supplementation enhances forearm and calcaneus bone acquisition in children, supporting the benefits of daily milk consumption.
OBJECTIVE: This study evaluated the impact of dairy supplementation on bone acquisition in children\'s limbs through a cluster-randomized controlled trial and a meta-analysis.
METHODS: The trial involved 315 children (4-6 year) from Northwest China, randomized to receive either 390 ml of milk daily (n = 215) or 20-30 g of bread (n = 100) over 12 months. We primarily assessed bone mineral density (BMD) and content (BMC) changes at the limbs, alongside bone-related biomarkers, measured at baseline, the 6th and 12th months. The meta-analysis aggregated BMD or BMC changes in the forearm/legs/calcaneus from published randomized trials involving children aged 3-18 years supplemented with dairy foods (vs. control group).
RESULTS: Of 278 completed the trial, intention-to-treat analysis revealed significant increases in BMD (4.05% and 7.31%) and BMC (4.69% and 7.34%) in the left forearm at the 6th and 12th months in the milk group compared to controls (P < 0.001). The calcaneus showed notable improvements in BMD (2.01%) and BMC (1.87%) at 6 months but not at 12 months. Additionally, milk supplementation was associated with beneficial changes in bone resorption markers, parathyroid hormone (- 12.70%), insulin-like growth factor 1 (6.69%), and the calcium-to-phosphorus ratio (2.22%) (all P < 0.05). The meta-analysis, encompassing 894 children, indicated that dairy supplementation significantly increased BMD (SMD, 0.629; 95%CI: 0.275, 0.983) and BMC (SMD, 0.616; 95%CI: 0.380, 0.851) (P < 0.05) in the arms, but not in the legs (P > 0.05).
CONCLUSIONS: Milk supplementation significantly improves bone health in children\'s forearms, underscoring its potential as a strategic dietary intervention for bone development. Trial registration NCT05074836.
OBJECTIVE: This study evaluated the impact of dairy supplementation on bone acquisition in children\'s limbs through a cluster-randomized controlled trial and a meta-analysis.
METHODS: The trial involved 315 children (4-6 year) from Northwest China, randomized to receive either 390 ml of milk daily (n = 215) or 20-30 g of bread (n = 100) over 12 months. We primarily assessed bone mineral density (BMD) and content (BMC) changes at the limbs, alongside bone-related biomarkers, measured at baseline, the 6th and 12th months. The meta-analysis aggregated BMD or BMC changes in the forearm/legs/calcaneus from published randomized trials involving children aged 3-18 years supplemented with dairy foods (vs. control group).
RESULTS: Of 278 completed the trial, intention-to-treat analysis revealed significant increases in BMD (4.05% and 7.31%) and BMC (4.69% and 7.34%) in the left forearm at the 6th and 12th months in the milk group compared to controls (P < 0.001). The calcaneus showed notable improvements in BMD (2.01%) and BMC (1.87%) at 6 months but not at 12 months. Additionally, milk supplementation was associated with beneficial changes in bone resorption markers, parathyroid hormone (- 12.70%), insulin-like growth factor 1 (6.69%), and the calcium-to-phosphorus ratio (2.22%) (all P < 0.05). The meta-analysis, encompassing 894 children, indicated that dairy supplementation significantly increased BMD (SMD, 0.629; 95%CI: 0.275, 0.983) and BMC (SMD, 0.616; 95%CI: 0.380, 0.851) (P < 0.05) in the arms, but not in the legs (P > 0.05).
CONCLUSIONS: Milk supplementation significantly improves bone health in children\'s forearms, underscoring its potential as a strategic dietary intervention for bone development. Trial registration NCT05074836.
摘要：
牛奶对农村学龄前儿童骨骼健康的影响研究不足。这项研究,通过临床试验和荟萃分析，发现补充牛奶可以增强儿童的前臂和跟骨骨骼的获取，支持日常牛奶消费的好处。
目的：本研究通过一项整群随机对照试验和一项荟萃分析，评估了乳制品补充剂对儿童四肢骨获取的影响。
方法：该试验涉及来自中国西北地区的315名儿童（4-6岁），在12个月内随机接受每日390毫升牛奶（n=215）或20-30克面包（n=100）。我们主要评估四肢骨矿物质密度（BMD）和含量（BMC）的变化，与骨骼相关的生物标志物，在基线测量，第6个月和第12个月。荟萃分析汇总了前臂/腿/跟骨的BMD或BMC变化，这些随机试验涉及3-18岁儿童补充乳制品（与对照组)。
结果：在完成试验的278人中，意向治疗分析显示,与对照组相比,牛奶组患者在第6个月和第12个月时,左前臂BMD(4.05%和7.31%)和BMC(4.69%和7.34%)显著增加(P<0.001).跟骨在6个月时BMD（2.01％）和BMC（1.87％）显着改善，但在12个月时未见改善。此外,补充牛奶与骨吸收标志物的有益变化有关，甲状旁腺激素（-12.70%），胰岛素样生长因子1（6.69％），钙磷比(2.22%)(均P<0.05)。荟萃分析，包括894名儿童，表明乳制品补充显着增加骨密度(SMD，0.629；95CI：0.275，0.983）和BMC（SMD，0.616；95CI：0.380，0.851）（P<0.05），但不在腿部（P>0.05）。
结论：补充牛奶可显著改善儿童前臂的骨骼健康，强调其作为骨骼发育战略饮食干预的潜力。试验注册NCT05074836。
目的：本研究通过一项整群随机对照试验和一项荟萃分析，评估了乳制品补充剂对儿童四肢骨获取的影响。
方法：该试验涉及来自中国西北地区的315名儿童（4-6岁），在12个月内随机接受每日390毫升牛奶（n=215）或20-30克面包（n=100）。我们主要评估四肢骨矿物质密度（BMD）和含量（BMC）的变化，与骨骼相关的生物标志物，在基线测量，第6个月和第12个月。荟萃分析汇总了前臂/腿/跟骨的BMD或BMC变化，这些随机试验涉及3-18岁儿童补充乳制品（与对照组)。
结果：在完成试验的278人中，意向治疗分析显示,与对照组相比,牛奶组患者在第6个月和第12个月时,左前臂BMD(4.05%和7.31%)和BMC(4.69%和7.34%)显著增加(P<0.001).跟骨在6个月时BMD（2.01％）和BMC（1.87％）显着改善，但在12个月时未见改善。此外,补充牛奶与骨吸收标志物的有益变化有关，甲状旁腺激素（-12.70%），胰岛素样生长因子1（6.69％），钙磷比(2.22%)(均P<0.05)。荟萃分析，包括894名儿童，表明乳制品补充显着增加骨密度(SMD，0.629；95CI：0.275，0.983）和BMC（SMD，0.616；95CI：0.380，0.851）（P<0.05），但不在腿部（P>0.05）。
结论：补充牛奶可显著改善儿童前臂的骨骼健康，强调其作为骨骼发育战略饮食干预的潜力。试验注册NCT05074836。
