强化钙与维生素D牛奶对北京城区小学女生骨量的影响

目的 :　探讨饮用钙与维生素 D强化牛奶对北京城区青春前期女生骨量的影响。方法 :　为期一年设有对照的双盲干预研究。将来自北京市西城区 9所小学平均年龄为 1 0 .1岁的女生 75 7名随机分为对照组 (n=2 5 9) :保持日常饮食 ;实验 1组 (n=2 3 8) :除日常饮食外 ,饮用钙强化牛奶 1 3 7ml/d,含钙 2 3 3 mg;实验 2组 (n=2 6 0 ) :除日常饮食外 ,饮用钙和维生素 D强化牛奶 1 3 7ml/d,其中钙 2 3 3 mg,VD 3 .3μg。使用 2 4 h回顾法了解食物摄入、体力活动问卷了解体力活动情况 ,用双能 X线吸收仪 (DEXA)测定全身和前臂骨量。结果 :　与干预前相比 ,实验组 2全身骨矿物密度 (BMD)的增长率显著高于实验 1组和对照组 (9.6 %、8.3 %和 8.0 % ,P=0 .0 0 2 ) ;实验 1组、实验 2组桡骨远端 1 /3处 BMC和骨面积的增长率显著高于对照组 (BMC:1 3 .0 %、1 2 .9%和1 1 .7% ,P=0 .0 1 6 ;骨面积 :2 .3 %、2 .0 %和 1 .5 % ,P=0 .0 1 0 ) ;实验 1组前臂远端 1 /1 0处 BMC和BMD的增长率显著高于对照组 (P=0 .0 0 7)。结论 :　饮用钙与维生素 D强化牛奶能促进青春前期女生骨量的增长 ,饮用钙和维生素 D强化牛奶促进骨量增长的作用比饮用钙强化牛奶明显     

饮用强化牛奶对青春期女生发育状况的影响研究

目的观察补充强化钙与维生素D的牛奶对青春期女生体格发育的影响,为促进青春期女生体格发育的研究提供依据。方法选取北京市9所小学498名女生(平均年龄10.1岁),分为对照组(保持日常饮食)、实验A组(除日常饮食外,饮用钙强化牛奶144 mL/d)和实验B组(除日常饮食外,饮用钙和维生素D强化牛奶144 mL/d),干预2 a及停止干预3 a后,进行追踪调查。结果干预2 a后,实验A组、实验B组学生身高、体重、骨密度增长值均明显高于对照组;停止干预3 a后,实验B组的身高、体重增长值明显低于对照组,实验A组身高、体重的增长值与对照组差异无统计学意义,且3组骨密度增长值均呈负增长。结论保证持续、充足的钙和维生素D摄入,有利于促进青春期女生的生长发育。     

儿少卫生

050384　强化钙与维生素D牛奶对北京城区小学女生骨量的影响/马冠生…∥营养学报2002,24(4)420～425探讨饮用钙与维生素D强化牛奶对北京城区青春前期女生骨量的影响。为期1年设有对照的双盲干预研究。将来自北京市西城区9所小学平均年龄为101岁的女生757名随机分为对照组(n=259):保持日常饮食;实验1组(n=238):除日常饮食外,饮用钙强化牛奶137mld,含钙233mg;实验2组(n=260);除日常饮食外,饮用钙和维生素D强化牛奶137mld,其中钙233mg,VD33μg。使用24h回顾法了解食物摄入、体内活动问卷了解体力活动情况,用双能X线吸收仪(DEXA)测定全身和…     

补钙16个月对青春期男女生骨量的影响

目的探讨不同钙摄入量对我国青少年骨量的影响。方法对北京郊区337人(平均年龄为13.6岁)开展为期16个月的双盲对照干预研究,每天给予3次不同剂量碳酸钙片,每片含60IU维生素D,用双能X线吸收仪(DXA)测定全身、腰椎和前臂骨量。结果女生全身骨矿物密度的年增长率由低钙摄入组到高钙摄入组逐渐升高,调整混杂因素后差异消失。女生前臂远端1/3处和男生前臂远端1/10处的骨矿物含量年增长率和骨面积年增长率均以每天钙摄入900～1100mg/d的人群(平均钙摄入量984mg/d)最高,其中调整混杂因素后男生差异消失。结论青春期钙摄入量达到1000mg/d以上可促进青少年骨量增长,此结果有性别差异。     

补充钙剂对青春期骨矿含量的影响

为研究补充钙剂对青少年骨矿含量以及体格发育的影响 ,选取 1 61例 9～ 2 0岁健康青少年 ,按性别和性发育程度分为补钙组和对照组。实验前后评价两组膳食钙摄入量、运动量水平、性发育程度 ,并测定两组青少年身高、体重和桡骨远端 1 3处骨矿含量、骨宽和血清总碱性磷酸酶水平。结果表明本组青少年膳食钙摄入量低于每日膳食钙参考摄入量的适宜摄入量水平 ,补充钙剂对青少年身高、体重无明显影响 ;骨矿含量增长除女性青春期后期有显著性差异外 ,其余各组增长与对照组比较无显著性。结果提示 ,青春期存在体格快速发育和骨量迅速积累的特点 ,补充钙剂对骨矿含量的增长作用有限 ,对体格发育也无明显影响 ;在女性骨量增长较少阶段补充钙剂则可能有助于骨矿含量的增加 ,且这种作用可能通过降低骨代谢率实现     

饮用强化牛奶改善小学女生营养状况的研究

目的 了解饮用强化牛奶对小学女生营养状况的影响情况,为学生饮用奶的推广实施奠定基础.方法 抽取黑龙江省密山市3所小学四年级学生300名,随机分成实验组1(每人每天饮用含钙400 mg的伊利纯牛奶250 mL)、实验组2(每人每天饮用含钙400 mg的伊利牛奶250 mL,添加维生素D8μg)和对照组(无干预措施),实验时间为2005年3月1日至12月10日.于干预前后进行营养学及人体指标的各项检测.结果 膳食中总能量、蛋白质、碳水化合物摄入量均以实验组2最高,实验组1居中,对照组最低.干预前后3组学生身高增长率差异无统计学意义,体重增长率实验组2高于实验组1和对照组.结论 在补充钙的同时补充维生素D对骨量增长的促进作用比单纯补充钙明显.补充牛奶可能会促进体重的增长,对身高增长影响不显著.     

强化钙与维生素D牛奶对10～12岁女童体格发育的影响

目的 探讨补充强化钙与维生素D牛奶对我国10－12岁女童体格发育的影响。方法 1999年3月至2001年3月,我们进行了为期2年、设有对照的双盲干预实验。将北京市9所小学757名平均年龄10.1岁的女童分为对照组（259人,保持日常饮食）、A组（238人,除日常饮食外,饮用钙强化牛奶144ml/d)和B组（260人,除日常饮食外,饮用钙和维生素D强化牛奶144ml/d)。调查其食物摄入和体力活动情况。干预前、中、后测定研究对象的体重、身高、坐高及膝高。结果 干预2年后,A组和B组的身高增长率（9.52%和9.26%)显著高于对照组的8.59%;A组和B组的体重增长率（34.53%和35.38%)显著高于对照组的30.91%;A组的坐高增长率为9.21%,显著高于B组的8.58%,又高于对照组的7.87%;A组膝高的增长率为9.00%,显著高于B组（8.37%)和对照组（8.44%)。结论 长期补充强化钙与维生素D的牛奶可能会促进我国10－12岁女童的体格发育。     

雌激素受体基因XbaI多态性与补钙对青春期少女骨骼发育作用的关系

目的研究雌激素受体(ER)基因XbaI多态性与补钙对青春期少女骨骼发育作用的关系,为制定钙膳食参考摄入量提供科学依据。方法从志愿者中选取88名13~15岁青春期少女,随机分为补钙组和对照组,并按XbaI多态性分成不同的亚组,进行为期1年的补钙实验。在补钙前后测定全身各部位骨密度、骨钙素(BGP)、骨碱性磷酸酶(BAP)、抗酒石酸酸性磷酸酶(TRACP)、雌二醇(E2)及维生素D水平。比较不同基因亚型间补钙后骨密度增长或骨生化指标变化的差异。结果共72人完成了整个研究。经过1年的干预,补钙组BGP的增长及前臂远端1/10处的骨密度增长均大于对照组;补钙组内的Xx亚型反映骨形成的指标BAP的增长大于xx亚型,且全身各测量部位的骨密度增长值均大于xx亚型,但无显著性差异;而对照组内各XbaI亚型上述各指标的增长值未见统计学差异。结论XbaI多态性中Xx较xx亚型具有更好的补钙反应性,在今后的补钙干预中应考虑该遗传因素的影响。     

性激素对青春早期学生骨量的影响

探讨不同性激素水平对青春早期学生的骨量增长的影响,为了解性激素与青春期骨骼发育关系提供理论依据.方法 整群抽取北京市怀柔区学生共197名,采用连续3d的24h膳食问卷回顾法了解膳食钙摄入情况.采用双能量X线骨密度测量仪(DEXA)测量全身骨量并计算出骨量年增长值及骨量年增长率,同时测定男生血清睾酮与女生血清雌二醇水平,按性激素水平P25和P75为界限将研究对象分为性激素水平高、中、低3组,比较3组间的骨量年增长值及年增长率.结果 男、女生不同性激素水平组间的膳食钙总摄入差异均无统计学意义(P值均>0.05).男生低睾酮组全身骨密度的年增长值和年增长率低于中睾酮组和高睾酮组(P值均<0.01),不同睾酮组间的骨矿物含量的年增长值和年增长率差异均无统计学意义(P值均>0.05).女生高雌二醇水平组全身骨密度、骨矿物含量的年增长值和年增长率显高于中雌二醇组和低雌二醇组(P<0.05).结论 青春早期学生性激素水平对骨量增长作用有性别差异,男生体内睾酮水平较高,骨密度年增长率也较高;女生体内雌二醇水平较高者的骨量年增长率较低.     

四川阿坝州藏羌汉族儿童青少年骨量比较研究

目的 分析四川省阿坝藏羌自治州藏、羌和汉族儿童少年的骨量状况，为西部少数民族地区儿童青少年生长发育的研究提供依据。方法 用双能X线前臂骨密度测量仪（pDEXA）测量1822名7-19岁藏、羌、汉族男女学生前臂远端1／10处和近端1／3处尺骨和桡骨（Dist．R＋U，Prox．R＋U）以及近端1／10处桡骨（Prox．R）的骨矿物密度（BMD）、骨矿物含量（BMC）、骨面积（BA）。结果 11，16，18岁女生和12，16，17岁男生的前臂骨量各项指标民族间差别无统计学意义；其他多个年龄段，藏族学生前臂远端骨量（特别是9～12岁男生 Dist．R＋U BMD及Dist．R＋U BMC）、前臂近端骨面积（Prox．R＋U BA）和近端桡骨骨面积（Prox，R BA）显著高于汉族和羌族；羌族学生骨量水平处于藏族和汉族之间；汉族13岁女生Dist．R＋U BA和Prox．R BMD显著高于本族同龄男生．羌族11岁女生Prox．R＋U BMC和Pwx．R BMC以及1l，12岁女生Dist．R＋U BA显著高于本族同龄男生，藏族15岁女生Dist．R＋U BA显著高于本族同龄男生，在其他年龄段各项骨量指标均为男生大干或等于女生。不同民族出现骨量性别差异的年龄不尽相同；男生在13-18岁、女生在11～16岁，Prox．R＋U BMD增长幅度明显大于Dist．R＋U BMD。结论四川藏、羌、汉族儿童青少年骨量存在差异。是否为遗传因素起作用尚需进一步深入研究。     

钙摄入量对青春前期女童骨量增长的影响—两年随机干预实验

目的研究不同钙摄入量对于青春前期女童骨量增长的影响,为该人群钙适宜摄入量的修订提供科学依据。方法以年龄10.0±0.7岁的241名青春前期健康女童为对象,设计普通膳食组、牛奶补充组和钙剂补充组三组,总钙摄入量分别为600、900和1200mg/d,进行2年干预,采用多次称量及3d膳食询问法获得2年间日均膳食钙摄入量,使用双能X线骨密度仪测量干预前后全身、腰椎及近端股骨骨矿物密度和骨矿物含量。结果2年间三组的平均钙摄入量分别为552±61、864±139和1166±207mg/d;日均钙摄入量与全身、多位点骨矿物含量和骨矿物密度显著正相关;当日均钙摄入量达到864mg/d时,全身骨矿物含量增加值显著高于钙摄入量为552mg/d膳食组;当日均钙摄入量达到1166mg/d时,股骨颈骨矿物含量及骨矿物密度和腰椎骨矿物密度的增加值显著高于未达到1166mg/d的干预组。结论9～11.5岁的青春前期女童钙摄入量达到1166mg/d,全身特别是负重部位能获得较高骨矿物含量和骨矿物密度增长,提示青春前期钙适宜摄入量可能为1200mg/d。     

Effects of two years' milk supplementation on size-corrected bone mineral density of Chinese girls

Much existing data on the effects of calcium or milk products on bone mineral accretion are based on bone mineral content (BMC) or areal bone mineral density (aBMD), neither of which accounts for changing bone size during the growing period. The aim of this study was to investigate the effects of 2-year milk supplementation on total body size-corrected BMD in Chinese girls with low habitual dietary calcium intake. Chinese girls aged 10 years were randomised, according to their school, to receive calcium fortified milk (Ca milk), or calcium and vitamin D fortified milk (CaD milk) for two years or act as unsupplemented controls. Dual-energy X-ray absorptiometry total body bone measures were obtained from 345 girls at baseline and 2 years. Size-corrected total body and regional BMD was calculated as: BMDsc = BMC/BApc, where pc was the regression coefficient of the natural logarithm transformed total body BMC and bone area. After 2 years, both supplemented groups had significantly greater gain in BMDsc of total body (3.5-5.8%, p < 0.05) and legs (3.0-5.9%, p < 0.05) than did the control group. Milk supplementation showed positive effects on bone mineral accretion when accounting for the changing skeletal size during growth. The effects were mainly on the lower limbs.     

Effects of dairy food supplements on bone mineral density in teenage girls

Summary Background Bone mineral density (BMD) is largely genetically determined and this influence is most powerful in the period of rapid skeletal development in childhood and late adolescence but environmental factors such as exercise and dietary calcium intake may influence up to 20%. Aims of the study The aims of the study were to examine healthy late adolescent females for the effects and benefits of a high calcium intake from dairy product foods on bone mineral density, body composition, lipids and biochemistry. The secondary aim is determine whether a high intake of dairy product foods in the diet is acceptable for this age group long term. Methods Ninety-one teenage girls who participated in a two-year randomised controlled study on the effect of dairy food supplementation on dietary patterns, body composition and bone density in post-pubertal teenage girls were approached one year after the cessation of the study to determine the effects of the cessation of dairy supplements on bone mineral density, dietary habits, biochemical markers, body composition and blood lipids. Bone mineral density and bone mineral content were assessed at the hip, spine and total body. Anthropometric data were collected, and exercise, Tanner, dietary assessment, preference and compliance questionnaires were administered. Lipid profiles, hydroxyproline excretion and urinary calcium and sodium excretion measurements were performed. Results There were no significant differences between the 2 groups for height, weight, lean and fat mass. The supplemented group had significantly higher calcium, phosphorus and protein intake during the supplementation period (p<0.001). No differences were seen between the groups 12 months after supplementation finished. There were no significant differences in exercise level, preference or acceptability of dairy products or in the lipids and bone markers between baseline the end of supplementation and 1 year follow-up. There was a significant increase in trochanter (4.6%), lumbar spine (1.5%) and femoral neck (4.8%) BMD (p<0.05) in the high calcium group at the end of supplementation. There was an increase in bone mineral content at the trochanter (p<0.05) and lumbar spine; however the latter was not statistically significant, in the high calcium group at the end of supplementation. There was no difference in vertebral height or width at any stage of the study, indicating no influence on bone size. Conclusions In this 3 year study (2 years of supplementation, 1 year follow-up), teenage girls, aged 15–18 years, were able to significantly increase their BMD at the trochanter, femoral neck and lumbar spine when supplemented with dairy product foods to a mean calcium intake of 1160 mg/d. There was also an effect seen on the BMC particularly at the trochanter and to a lesser extent at the lumbar spine. The dietary calcium intake achieved did not adversely affect body weight, fat and lean mass or blood lipid profiles. Twelve months after the supplementation finished the girls had returned to their baseline diet, indicating self-selection of a high dairy product diet may be hard to achieve. Received: 5 June 2000, Accepted: 5 September 2000     

Calcium supplementation and bone mineral accretion in adolescent girls: an 18-mo randomized controlled trial with 2-y follow-up

BACKGROUND: A recent meta-analysis raised doubt as to whether calcium supplementation in children benefits spine and hip bone mineral density (BMD). OBJECTIVE: We used state-of-the-art measures of bone (fan-beam dual-energy X-ray absorptiometry and 4 bone turnover markers) to determine whether girls with low habitual calcium intake benefited from supplementation with a soluble form of calcium (calcium citrate malate dissolved in a fruit drink). DESIGN: The trial was an 18-mo randomized trial of calcium supplementation (792 mg/d) with follow-up 2 y after supplement withdrawal. Subjects were 96 girls (mean age: 12 y) with low calcium intakes (mean: 636 mg/d). The main outcome measure was change in total-body, lumbar spine, and total hip bone mineral content (BMC) during supplementation and 2 y after supplement withdrawal. Changes in BMD and bone turnover markers were secondary outcome measures. RESULTS: The mean additional calcium intake in the supplemented group was 555 mg/d. Compared with the control group, the supplemented group showed significantly (P < 0.05) greater gains in BMC (except at the total hip site) over the 18-mo study. BMD change was significantly (P < 0.05) greater for all skeletal sites, and concentrations of bone resorption markers and parathyroid hormone were significantly (P < 0.01) lower in the supplemented group than in the control group after 18 mo. After 42 mo, gains in BMC and BMD and differences in bone resorption were no longer evident. CONCLUSIONS: Calcium supplementation enhances bone mineral accrual in teenage girls, but the effect is short-lived. The likely mechanism for the effect of the calcium is suppression of bone turnover, which is reversed upon supplement withdrawal.     

The skeletal benefits of calcium- and vitamin D3-fortified milk are sustained in older men after withdrawal of supplementation: an 18-mo follow-up study

BACKGROUND: In a previous 2-y randomized controlled trial, we showed that calcium- and vitamin D3-fortified milk stopped or slowed bone loss at several clinically relevant skeletal sites in older men. OBJECTIVE: The present study aimed to determine whether the skeletal benefits of the fortified milk were sustained after withdrawal of the supplementation. DESIGN: One hundred nine men >50 y old who had completed a 2-y fortified milk trial were followed for an additional 18 mo, during which no fortified milk was provided. Bone mineral density (BMD) of the total hip, femoral neck, lumbar spine, and forearm was measured by using dual-energy X-ray absorptiometry. RESULTS: Comparison of the mean changes from baseline between the groups (adjusted for baseline age, BMD, total calcium intake, and change in weight) showed that the net beneficial effects of fortified milk on femoral neck and ultradistal radius BMD at the end of the intervention (1.8% and 1.5%, respectively; P < 0.01 for both) were sustained at 18-mo follow-up (P < 0.05 for both). The nonsignificant between-group differences at the total hip (0.8%; P = 0.17) also persisted at follow-up (0.7%; P = 0.10), but there were no lasting benefits at the lumbar spine. The average total dietary calcium intake in the milk supplementation group at follow-up approximated recommended amounts for Australian men >50 y old (1000 mg/d) but did not differ significantly from that in the control subjects (1021 versus 890 mg/d). CONCLUSION: Supplementation with calcium- and vitamin D3-fortified milk for 2 y may provide some sustained benefits for BMD in older men after withdrawal of supplementation.     

Effects of school milk intervention on cortical bone accretion and indicators relevant to bone metabolism in Chinese girls aged 10-12 y in Beijing

BACKGROUND: We previously reported that increased milk consumption enhances growth and bone mineral accretion in Chinese girls aged 10-12 y. OBJECTIVE: Our objective was to evaluate the effects of milk supplementation on cortical bone accretion and to study the physiologic mechanisms underlying the observed changes in bone. DESIGN: Chinese girls aged 10 y were randomly assigned into calcium-fortified milk (Ca milk), calcium and vitamin D-fortified milk (CaD milk), and control groups according to their schools in a 24-mo school milk intervention trial. Periosteal and medullary diameters of metacarpal bone were measured at baseline and 24 mo in the Ca milk (n = 177), CaD milk (n = 210), and control (n = 219) groups. Insulin-like growth factor I (IGF-I), parathyroid hormone (PTH), bone alkaline phosphatase (BAP), osteocalcin, and deoxypyridinoline concentrations were measured at baseline and at 12 and 24 mo in the Ca milk (n = 43), CaD milk (n = 44), and control (n = 41) groups. RESULTS: After adjustment for pubertal status and clustering by school, 24-mo supplementation led to greater increases in periosteal diameter (1.2%) and cortical thickness (5.7%) and to smaller gains in medullary diameter (6.7%) than did the control (P < 0.05). The CaD milk group had lower serum BAP at 12 mo (19.9%) and lower serum PTH at 12 (46.2%) and 24 (16.4%) mo than did the control group (P < 0.05). The effect of milk supplementation on increasing IGF-I concentrations at 24 mo (16.7-23.3%) was significant in individual analyses but not after adjustment for clustering by school. CONCLUSIONS: Milk supplementation showed positive effects on periosteal and endosteal apposition of cortical bone.