短期增加饮奶对生长突增期女孩骨密度和身高的影响

Effect of short term milk drinking on bone mineral density in healthy girls during spurt growth period

目的了解生长突增期女孩短期(2年)增加饮用牛奶后其骨密度(BMD)和身高的变化情况。方法对375例发育正常女孩行全身扫描和左前臂扫描,随机分为实验组(添加牛奶组)和对照组,1年和2年后,用同一台双能X线骨密度仪再次测量,观察两组间BMD的变化。结果首次测量:实验组与对照组各部位BMD值、全身总的骨矿含量(BMC)值和身高无差异(P>0.05)。1年和2年后测量结果均显示:两组间各部位BMD、BMC值比较仍无明显差异(P>0.05),两组在两年中平均身高增长速率几乎一样(12和11.9cm)。分别将两组3次测量结果进行自比:各部位的BMD值第2次高于第1次(P<0.01～0.001),第3次与第2次相比,仅前臂远端1/10处的BMD值有显著性增加(P<0.001),而前臂远端1/3处BMD值和全身总的BMD值却明显下降(P<0.001)。全身总的BMC值总是随年龄增加而逐渐增长(P<0.001)。结论生长突增期女孩短期(2年)饮用牛奶其BMD值无显著性改变,且与身高的增长无关。

Objective To observe changes in bone mineral density (BMD) and the speed of height growth in healthy girls during spurt growth period after a short term milk drinking (a period of two years).Methods 375 healthy girls having under gone whole body and left forearm scanning for BMD were divided into milk drinking group(255) and control group(120).The second and the third measurement had been done by same dual energy X ray bone densitometer after one and two year.Results The primary measurement results showed that there were no significant difference in BMD and bone mineral content (BMC) and height between milk drinking and control group(P >0.05). The second and the third measurement results showed that there were no significant difference in BMD and BMC between two groups(P >0.05).The speed of height growth was the similarity in two groups (12 and 11.9cm).The second measurements were higher than the first measurements in both groups(P< 0.01～0.001).BMD of the distal 1/10 left forearm in the third measurements were significantly higher than the second measurements(P< 0.001),but BMD of the distal 1/3 left forearm and BMD of total body decreased significantly in the third measurement(P< 0.001).However,BMC of total body were always increased significantly with their age.Conclusion Milk products given in a short term did not affect the BMD quantity, and had no correlation with the speed of height growth.