膳食钙摄入量与青春前期女童骨量关系的研究

目的:研究青春前期女童膳食钙摄入量与骨量的关系,为指导合理钙营养提供科学依据。方法:采用双能X线骨密度测量仪测量年龄在10±1岁的194名青春前期女童全身及多位点骨密度和骨矿物质含量,采用食物频数及3d膳食询问法调查膳食钙摄入量,问卷法调查体力活动。结果:日均钙摄入量与所测各位点骨矿物质含量及骨密度均呈显著正相关;日均钙摄入量平均从257mg增加到759mg,不同位点的骨矿物质含量和骨密度分别增加13%～22%和3.6%～16%。结论:增加青春前期女童膳食钙摄入量有助于获得较高骨量和骨密度。     

广东大学生骨量与膳食营养体力活动的相关性

了解广东省大学生骨骼生长同发育现状及其与膳食营养摄入和体力活动水平的关系,为维护大学生骨骼正常生长发育提供参考.方法 采用双能X线骨密度测量仪,测量广东省212名18~ 22岁青年全身骨矿物含量(BMC)和骨密度(BMD).采用问卷调查方法获得研究对象膳食营养摄入及体力活动情况.结果 男生全身BMD(1.0 g/cm2)显著高于女生(0.9 g/cm2) (P<0.05),男生全身BMC(2 779.3 g)与女生(2 176.9 g)差异有统计学意义(P<0.05).女生膳食脂肪、维生素D摄入量与全身BMD、BMC均呈正相关(P值均<0.05),男生钙摄入量与BMD呈正相关,膳食能量、蛋白质、脂肪、维生素D摄入量及体力活动强度与全身BMD、BMC均呈正相关(P值均<0.05).结论 膳食营养素和体力活动可影响广东青年全身骨矿物含量和骨密度.     

补钙对大鼠峰值骨量形成和预防骨质疏松的作用

目的 :　探讨补钙对峰值骨量的影响及对绝经后骨质疏松发生的预防作用。方法 :　选用雌性大鼠喂给不同钙含量的饲料至 1 0 mo龄 ,半数动物断头处死 ,取股骨进行相关检测 ,了解不同钙摄入量对骨峰值的影响。半数动物行卵巢切除术 ,喂饲 1 0 w后断头处死 ,取股骨进行有关检测 ,了解不同峰值骨量对骨质疏松的预防作用。结果 :　高钙摄入组峰值期大鼠股骨骨密度、骨重、骨长度、骨皮质厚度和股骨最大载荷、骨应变量等值均较低钙摄入组高 ;去卵巢后各组骨密度均降低 ,但高钙摄入量大鼠股骨骨密度比低钙摄入量大鼠的高。结论 :　钙摄入量的增加能有效提高峰值骨量 ,较高的峰值骨量能延缓骨质疏松的发生和降低骨折发生的危险性     

绝经后妇女体力活动水平与骨密度的关系

目的检验绝经后妇女体力活动(PA)总量及不同强度PA与骨密度(BMD)和骨盐含量(BMC)的关联。方法从广州市社区招募315名50～70岁停经妇女。通过面对面访问调查其日常PA情况及一般情况和膳食情况等相关协变量。采用双能X-光骨密度仪检测全身、腰椎(L1-L4)及左侧股骨(总股骨、股骨颈、大粗隆、股骨干和Wards区)的BMD和BMC。结果以PA能量代谢当量(MET值)进行三等分位法分组,协方差分析结果显示总体上各部位BMD和BMC随PA总量增加而呈增高的趋势。PA总量低、中、高水平组全身BMD的均值(SE)分别为(1.045±0.008),(1.043±0.008),(1.068±0.008)g/cm2,高PA组显著高于低和中PA组(P=0.049和0.028)。其他部位BMD在三组间无统计学差异意义(P>0.05)。高PA组总股骨、股骨颈、股骨干和Wards区的BMC显著高于低PA组(P=0.004～0.042)。不同强度PA对BMD影响不同,低强度PA越少、中等强度PA越多以及适量的高强度PA均增加BMD。结论较高的PA水平,尤其是增加中等强度和适量的高强度PA更有利于绝经后妇女的骨质健康。     

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。     

中老年人营养素摄入量与骨密度关系的研究

目的 探讨中老年人营养素摄入量与骨密度的关系.方法 对200名在北京协和医院健康体检者进行膳食调查及测量腰椎(L)2～4、股骨大粗隆及股骨颈的骨密度,并分为中青年男女组、老年前期男女组和老年男女组,各组及性别间进行比较.结果 男性老年组平均每日蛋白质、碳水化合物、热量的摄入量分别为(71.4±11.7)g、(294.2±54.7)g和(2196.9±311.3)kcal,显著低于男性中青年组;男性中青年组平均每日蛋白质、碳水化合物、热量的摄入量分别为(91.7±19.5)g、(81.8±85.2)g和(2716.0±451.7)kcal.钙摄入量以女性老年组为最低,平均每日摄入量为(362.0±167.1)mg;男性老年组L2～4、股骨大粗隆及股骨颈的骨密度异常发生率显著高于男性中青年组(P＜0.05)及男性老年前期组(P＜0.05);女性各组L2～4、股骨大粗隆及股骨颈的骨密度异常发生率的差异均有统计学意义(P＜0.05),尤以老年组和中青年组显著(P＜0.0001);男性老年前期组和老年组骨密度异常发生率显著低于女性老年前期组(P＜0.05)和女性老年组(P＜0.05).结论 影响老年女性骨密度异常的因素之一可能为钙摄入的减少,脂肪摄入量的增加可能是影响骨健康的因素之一.     

膳食矿物质与骨密度关系调查

目的 研究老年人膳食中矿物质含量对骨密度（BMD）的影响，探讨防治老年骨质疏松的措施。方法 对309例60岁以上老人进行了膳食调查及健康检查。结果 老年女性骨矿物质含量（BMC）和骨密度（BMD）显低于男性。健康老人平均每日摄入钙、锰、铜、硒的量男性均显高于女性。OP患与同性别健康老人每日矿物质摄入量相比，OP组钾钙、镁、铁、锰、锌、磷、来源于奶的钙（简称奶钙）、硒摄入量均显低于同性别健康老人组，BMD与钾、钙、镁、锌、铜、磷、硒、奶钙摄入量和钙磷比值均呈显正相关。结论 膳食矿物质与BMD存在一定的关系，膳食钾、钙、锌等摄入量不足可能导致BMD降低。     

绝经后妇女膳食调查及某些因素与骨密度的关系

目的：了解绝经后妇女的膳食营养状况，为骨质疏松的预防提供科学依据。方法：以问卷调查方式对894名绝经后妇女的膳食营养状况进行调查，并对某些因素与骨密度的关系进行相关分析。结果：与《中国居民膳食指南》相比，谷类食物，奶类及奶制品摄入量偏低，能量摄入充足；蛋白质，维生素C和铁的摄入量均超过RDA的100％，维生素B1超过RDA的85％；维生素B2和钙的摄入量明显不足，经常摄食奶类，豆类食品与骨密度呈显著的正相关。结论：绝经后妇女应适当增加谷类，奶类及豆制品的摄入。     

甲状旁腺激素基因多态性与钙摄入量对青春期女童骨量增长的交互作用

目的:探讨甲状旁腺激素(PTH)基因多态性与钙摄入量对青春期女童骨量增长的交互作用。方法:选择228名9～11.5岁未月经初潮的健康女童进行2年追踪,用双能X线骨密度仪(DEXA)检测对象追踪前后全身、左侧近端股骨(包括股骨颈、大转子、粗隆间和华氏三角区)、L1～L4腰椎骨矿含量和骨密度,采用PCR-RFLP技术检测PTH基因BstBⅠ位点多态性。结果:BB基因型女童L1～L4腰椎骨矿含量增长率、左侧近端股骨、粗隆间和L1-L4腰椎骨密度增长率均高于含b等位基因女童(P=0.022～0.047)。BB基因型女童在高钙摄入(>950mg/d)时,粗隆间骨矿含量(ITBMC)增长率较中等和低钙摄入时分别高29.4%和35.0%,股骨颈骨密度(FNBMD)增长率分别高66.7%和46.2%。而含b等位基因女童的ITBMC和FNBMD增长率在不同钙摄入量之间没有显著性差异。结论:PTH基因BstBⅠ多态性与钙摄入量对青春期女童骨量增长存在交互作用,BB基因型女童高钙摄入可促进其骨量增长。     

补钙对青年女性全身各部位骨密度的影响

目的探讨不同钙摄入量对我国青年女性全身及各部位骨密度的影响,为进一步研究制定我国居民钙的适宜摄入量提供科学依据。方法为期13个月设有对照的双盲干预研究。将某军校平均年龄19.8岁女学员179人,以基线调查的全身骨密度及膳食钙摄入量为指标,随机分为4组,每天给予不同剂量碳酸钙片,使总钙摄入量分别达到400、800、1000及1200mg/d,每片钙片中均强化60IU的维生素D。干预前后分别使用食堂记帐法、称重法和24小时记录法了解膳食摄入,体力活动问卷了解体力活动情况,双能X线骨密度仪测定全身、腰椎和前臂的骨密度。结果4组平均摄入的膳食钙加上补充钙的中位数分别是517mg/d(1组)、810mg/d(2组)、964mg/d(3组)、1185mg/d(4组)。实验前后各部位骨密度增加值的组间比较分析显示,3组和4组的全身、下肢和尺骨远端1/3处骨密度增加值均显著高于1组和2组(P<0.05);3组和4组的3处骨密度增加值差异均无显著性。结论随着钙摄入量的增加,青年女性全身各部位骨密度增加,当钙摄入量达到约1000mg/d时,全身、下肢和尺骨远端1/3处骨密度增加值达到最大,再增加钙摄入至1200mg/d时,骨密度不再显著增加。提示我国青年女性钙的适宜摄入量可能在1000mg/d左右。     

Dietary iron positively influences bone mineral density in postmenopausal women on hormone replacement therapy

The associations of dietary intakes of iron and calcium on change in bone mineral density (BMD) were examined over 1 y in healthy nonsmoking postmenopausal women (mean age 55.6 +/- 4.6 y) stratified by hormone replacement therapy (HRT) use (HRT, n = 116; no HRT, n = 112). BMD was measured at lumbar spine L(2)-L(4), trochanter, femur neck, Ward's triangle, and total body using dual-energy X-ray absorptiometry at baseline and 1 y. Mean nutrient intakes were assessed using 8-d diet records. All women received 800 mg/d of supplemental elemental calcium. Regression analyses examined the effects of iron and calcium intakes on BMD change adjusting for years past menopause, baseline BMD, weight change, exercise, and energy intake. The interaction of iron with calcium on BMD change was assessed using tertiles of iron and calcium intake and estimated marginal mean change in BMD. Iron was associated (P < or = 0.05) with greater positive BMD change at the trochanter and Ward's triangle in women using HRT. Calcium was associated (P < or = 0.05) with BMD change at the trochanter and femur neck for women not using HRT. In women using HRT in the lowest tertile of calcium intake, change in femur neck BMD increased linearly as iron intake increased. In women not using HRT, BMD increased in the women in the highest tertile of calcium intake. We conclude that HRT use appears to influence the associations of iron and calcium on change in BMD.     

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     

Spinal bone density and calcium intake in healthy postmenopausal women

Dietary calcium intake and bone mineral density (BMD) of the lumbar spine (L2-L4) were determined in 131 healthy free-living postmenopausal women (aged 64.7 +/- 7.6 y, means +/- SD). The calcium consumption for the total population was 606 +/- 302 mg/d. Subjects consuming less than the population mean of dietary calcium had significantly lower BMDs than did subjects with intakes above the mean (P less than 0.009); these two groups did not differ in basic demographic characteristics. Additional analyses using a stepwise univariate regression model demonstrated that BMD was significantly associated with body weight (P less than 0.001) and dietary calcium intake (P less than 0.02). These data support the hypothesis that dietary calcium intake is a determinant of skeletal health in postmenopausal women.     

Mother-daughter pairs: spinal and femoral bone densities and dietary intakes

Bone mineral density (BMD) of the lumbar spine (L1-L4) and femur (femoral neck, Ward's triangle, and trochanter) was measured in 37 healthy, white mother-daughter pairs by dual-photon absorptiometry. Mothers and daughters were aged 52 +/- 7 and 25 +/- 4 y (mean +/- SD), respectively. Three-day dietary intakes were evaluated. Significant correlations between mother-daughter pairs for BMD of all lumbar and femoral areas [except for L2 (r = 0.26, P = 0.054)] indicated familial resemblances in bone mineralization. Total calcium intake was significantly correlated with three BMD values for the daughters (L2, femoral neck, and trochanter) but not for the mothers. When mothers were classified as pre- (n = 20) or postmenopausal (n = 17), correlation coefficients for BMD were higher for premenopausal mothers and their daughters and lower for postmenopausal mothers and their daughters, except for the trochanter. The results suggest that the nature of inheritance of bone mass of women may have at least two components, one influencing the level of peak bone mass and one related to bone loss at menopause.     

大量饮酒对成年男性骨密度影响的回顾性分析

目的探讨大量饮酒对成年男性骨密度的影响。方法对219例成年男性查体资料进行回顾性分析,根据每日饮酒量分为大量饮酒组(98例)和非大量饮酒组(121例)。应用双能X线骨密度仪测定其腰椎和髋部骨密度,获得骨密度、骨矿含量、面积、T值和Z值。应用SPSS11.5统计软件对两组进行比较分析。结果大量饮酒组的腰椎骨密度和骨矿含量低于非大量饮酒组(1.09±0.17vs1.20±0.15g/cm2,P=0.001;67.86±13.84vs75.19±13.09g,P=0.001)。大量饮酒组股骨颈部位骨密度和骨矿含量低于非大量饮酒组(0.92±0.13vs0.97±0.12g/cm2,P=0.001;4.93±0.97vs5.22±0.81g,P=0.014)。两组的腰椎和股骨颈的面积均无统计学意义。根据T值,大量饮酒组的骨质疏松及低骨量的检出率(10.2%和32.7%)高于非大量饮酒组(分别为0%和14.9%),差别有统计学意义(P=0.001)。结论乙醇的毒害作用可导致骨量减低,戒酒有利于骨质疏松的干预。     

Dietary iron is associated with bone mineral density in healthy postmenopausal women

Healthy nonsmoking postmenopausal women (n = 242; ages 40-66 y) were included in the Bone, Estrogen, and Strength Training (BEST) Study. Bone mineral density (BMD) was measured at five sites (lumbar spine L2-L4, trochanter, femur neck, Ward's triangle and total body) using dual energy X-ray absorptiometry (DXA). Mean nutrient intakes were assessed using a 3-d diet record. Regression models were calculated using each BMD site as the dependent variable and iron as the independent variable. Covariates included in the models were years past menopause, fat-free mass, fat mass, use of hormone replacement therapy, total energy intake and dietary intake of protein and calcium. Using linear models, iron was associated with greater BMD at all sites (P < or = 0.01), even after adjusting for protein and/or calcium. Increasing levels of iron intake (>20 mg) were associated with greater BMD at several bone sites among women with a mean calcium intake of 800-1200 mg/d. Elevated iron intake was not associated with greater BMD among women with higher (>1200 mg/d) or lower calcium intakes (<800 mg/d). Dietary iron may be a more important factor in bone mineralization than originally thought and, its combined effect with calcium on BMD warrants exploration in future studies.     

Is caffeine associated with bone mineral density in young adult women?

BACKGROUND: By increasing the urinary excretion of calcium, caffeine consumption may reduce bone mineral density (BMD) and subsequently increase the risk for osteoporotic fracture. Although negative associations between caffeine consumption and BMD have been reported for postmenopausal women, in particular for those who consume low amounts of dietary calcium, the relation between caffeine and BMD in younger women is unclear. Therefore, we evaluated the association between caffeine consumption and BMD in a cross-sectional study of 177 healthy white women, age 19-26 years, who attended a Midwestern university. METHODS: Average caffeine intake (milligrams per day) was calculated from self-reports of the consumption of coffee, decaffeinated coffee, tea, colas, chocolate products, and select medications during the previous 12 months (mean caffeine intake = 99. 9 mg/day). BMD (grams per square centimeter) at the femoral neck and the lumbar spine was measured by dual-energy X-ray absorptiometry. RESULTS: After adjusting in linear regression models for potential confounders, including height, body mass index, age at menarche, calcium intake, protein consumption, alcohol consumption, and tobacco use, caffeine consumption was not a significant predictor of BMD. For every 100 mg of caffeine consumed, femoral neck BMD decreased 0.0069 g/cm(2) (95% confidence in terval [CI] = -0.0215, 0. 0076) and lumbar spine BMD decreased 0.0119 g/cm(2) (95% CI = -0. 0271, 0.0033). No single source of caffeine was significantly associated with a decrease in BMD. Furthermore, the association between caffeine consumption and BMD at either site did not differ significantly between those who consumed low levels of calcium (< or =836 mg/day) and those who consumed high levels of calcium (>836 mg/day). CONCLUSIONS: Caffeine intake in the range consumed by young adult women is not an important risk factor for low BMD.     

Vitamin D supplementation and bone mineral density in early postmenopausal women

BACKGROUND: Increased vitamin D intake may preserve or increase bone mineral density (BMD) in older persons. OBJECTIVE: A 2-y double-blind study was undertaken to determine whether weekly administration of 10 000 units of vitamin D(2) maintained or increased BMD in younger postmenopausal women more efficiently than did calcium supplements alone. DESIGN: One hundred eighty-seven women who were >or= 1 y postmenopausal were randomly assigned to take either 1000 mg Ca/d after the evening meal or 1000 mg Ca/d plus 10 000 U vitamin D(2)/wk in a double-blind, placebo-controlled format. The BMD of the proximal forearm, lumbar spine, femoral neck, Ward's triangle, and femoral trochanter was measured at 6-mo intervals by osteodensitometry. RESULTS: During the 2-y period, there was no significant difference in the change in BMD at any site between the subjects taking calcium supplements and those taking calcium plus vitamin D(2). Both groups significantly (P < 0.005) gained BMD in Ward's triangle and the femoral trochanter but significantly (P < 0.005) lost bone in the proximal radius. There was no significant change in the lumbar spine or femoral neck BMD. CONCLUSION: In younger postmenopausal women ( age: 56 y) whose average baseline serum 25-hydroxyvitamin D concentration was well within the normal range, the addition of 10 000 U vitamin D(2)/wk to calcium supplementation at 1000 mg/d did not confer benefits on BMD beyond those achieved with calcium supplementation alone.