Parathyroid hormone is elevated but bone markers and density are normal in young female subjects who consume inadequate dietary calcium

Dietary Ca and osteocalcin (OC), parathyroid hormone (PTH), 25-hydroxyvitamin D (25-OH-D), insulin-like growth factor (IGF)-I and sex hormone binding globulin (SHBG) were assessed simultaneously to bone mineral density (BMD) in 200 adolescent girls (aged 11-15 years) and 100 young women (aged 20-23 years), selected from the lowest and highest end of the Ca intake distribution of a larger population sample. Ca intake was evaluated by food frequency questionnaires, BMD was measured by dual energy x-ray absorptiometry at ultradistal and proximal radius of non-dominant arm, bone age was estimated from x-rays of left hand and wrist according to Tanner et al. (1983). Surprisingly, mean Ca intakes were below the dietary reference intakes in the subgroups of girls and women with the highest measured Ca consumption. Postmenarcheal, but not premenarcheal girls showed radial densities as high as the women and in no group was BMD associated with Ca intake. In all adolescents serum PTH was negatively related to dietary Ca. In girls before menarche IGF-I was positively associated with bone age, while in the same subjects the negative relationship between SHBG and BMD pointed to the crucial role of bioavailable sex steroids on bone mass apposition in early puberty. OC levels decreased progressively with age, while serum 25-OH-D significantly increased after menarche. In conclusion, although in adolescents low Ca intake has not been shown to induce any immediate deleterious effect on radial density, the compensatory hypersecretion of PTH supports the need for an adequate Ca intake to achieve peak bone mass.     

青春期学生膳食营养状况对骨量的影响

目的研究学生青春期膳食营养状况对骨量的影响,以增加骨峰值,预防骨质疏松的发生.方法抽取贵阳某高等院校239名青春期学生进行一般情况和食物摄入情况调查,再从摄入豆类、奶类和同时摄入豆类、奶类的学生中抽取60人分为3组,用双能X线骨密度仪测定前臂1/3处骨密度(BMD)及骨矿化物含量(BMC).结果 60例学生的热能及多种营养素的摄入水平很低,尤其是钙摄入量仅占现行供给标准的39%;结果还显示BMD降低率高达58.3%.3组学生的BMD、BMC差异无显著性.BMC、BMD与身高、体重及食物中蛋白质、能量、钙、磷等摄入量呈正相关.结论骨量较低与其膳食营养素摄入低有关.应加强营养宣教,提高膳食营养状况以增加骨量.     

Lower estimates of net endogenous non-carbonic acid production are positively associated with indexes of bone health in premenopausal and perimenopausal women

BACKGROUND: The link between acid-base homeostasis and skeletal integrity has gained increasing prominence in the literature. Estimation of the net rate of endogenous non-carbonic acid production (NEAP) from dietary protein and potassium content enables exploration of the effects of dietary acidity or alkalinity on bone. OBJECTIVE: The study aimed to ascertain whether lower dietary acidity (lower dietary protein intake but higher potassium intake-ie, low estimate of NEAP) was associated with greater axial and peripheral bone mass and less bone turnover, independent of key confounding factors. DESIGN: Baseline (cross-sectional) results of a population-based study were examined further. The database includes spine and hip bone mineral density (BMD) in 1056 premenopausal or perimenopausal women aged 45-54 y and forearm bone mass and the urinary markers of bone resorption in 62 women. A validated food-frequency questionnaire was used to measure dietary intakes. RESULTS: Lower estimates of energy-adjusted NEAP were correlated with greater spine and hip BMD and greater forearm bone mass (P < 0.02 to P < 0.05). Hip and forearm bone mass decreased significantly across increasing quartiles of energy-adjusted NEAP (P < 0.02 to P < 0.03), and trends at the spine were similar (P < 0.09). Differences remained significant after adjustment for age, weight, height, and menstrual status. Lower estimates of energy-adjusted NEAP were also correlated with lower excretion of deoxypyridinoline and were significant predictors of spine and forearm bone mass. CONCLUSIONS: These novel findings provide evidence of a positive link between a ratio of lower protein to higher potassium dietary intake (ie, less dietary acid) and skeletal integrity.     

Dietary influences on bone mass and bone metabolism: further evidence of a positive link between fruit and vegetable consumption and bone health?

BACKGROUND: The role of nutritional influences on bone health remains largely undefined because most studies have focused attention on calcium intake. OBJECTIVE: We reported previously that intakes of nutrients found in abundance in fruit and vegetables are positively associated with bone health. We examined this finding further by considering axial and peripheral bone mass and markers of bone metabolism. DESIGN: This was a cross-sectional study of 62 healthy women aged 45-55 y. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry at the lumbar spine and femoral neck and by peripheral quantitative computed tomography at the ultradistal radial total, trabecular, and cortical sites. Bone resorption was calculated by measuring urinary excretion of pyridinoline and deoxypyridinoline and bone formation by measuring serum osteocalcin. Nutrient intakes were assessed by using a validated food-frequency questionnaire; other lifestyle factors were assessed by additional questions. RESULTS: After present energy intake was controlled for, higher intakes of magnesium, potassium, and alcohol were associated with higher total bone mass by Pearson correlation (P < 0.05 to P < 0.005). Femoral neck BMD was higher in women who had consumed high amounts of fruit in their childhood than in women who had consumed medium or low amounts (P < 0.01). In a regression analysis with age, weight, height, menstrual status, and dietary intake entered into the model, magnesium intake accounted for 12.3% of the variation in pyridinoline excretion and 12% of the variation in deoxypyridinoline excretion. Alcohol and potassium intakes accounted for 18.1% of the variation in total forearm bone mass. CONCLUSION: The BMD results confirm our previous work (but at peripheral bone mass sites), and our findings associating bone resorption with dietary factors provide further evidence of a positive link between fruit and vegetable consumption and bone health.     

Dairy Products,Dietary Calcium and Bone Health: Possibility of Prevention of Osteoporosis in Women: The Polish Experience

The objective of the study was to analyze the consumption of dairy products and dietary calcium by women in the context of bone mineral density and to assess opportunities to prevent osteoporosis in a dietary manner. The study was carried out with 712 Polish women. In 170 women aged 32 to 59 bone mineral density (BMD) was measured. The data on the consumption of dairy products and dietary calcium and some other osteoporosis risk factors was collected from 712 women. The average calcium intake from a diet was 507 mg/day. Only 2% of the women met Polish calcium intake recommendations. During adulthood, dairy product consumption or dietary calcium intake did not differ significantly between women with low BMD (below −1 SD) and women with regular BMD (≥−1 SD) (47.4 vs. 44.3 servings/week and 459 vs. 510 mg/day, respectively, p > 0.05). The odds ratios adjusted for age, menstruation and BMI in women with upper BMD tercile in comparison to the reference group (bottom tercile) was 2.73 (95% CI: 1.14, 6.55; p < 0.05) for the daily consumption of dairy products during the pre-school period and 2.40 (95% CI: 1.01, 5.70; p < 0.05) for the daily consumption of dairy products during the school period. Two clusters of women were established. In the S1 cluster, low BMD (below −1 SD) was associated with older age (≥50 years), lack of menstrual cycle. In the S2 cluster, regular BMD (≥−1 SD) was related to younger aged women (<50 years), presence of menstrual cycle, consumption of higher level of dairy products (≥28 servings/week) during adulthood and daily intake of dairy products during childhood and adolescence. The results indicate that good bone health to the large extent depended upon the combined impact of dietary factors and some non-modifiable risk factors of osteoporosis such as age and the presence of menstruation. Consumption of dairy products in childhood and adolescence may improve bone mineral density and reduce the risk of osteoporosis in adult women.     

Familial resemblance of bone mineral density between females 18 years and older and their mothers.

Potential determinants of bone mass were investigated in a group of 70 young females (mean age 26.6 years), daughters of women studied in premenopause. Nutritional data, leisure physical activity level, lifestyle habits as well as familial similarities were assessed. The daughters' bone mineral density (BMD), measured by dual-energy absorptiometry, was significantly correlated with their body mass index (BMI) (r = 0.22), dietary vitamin D intake (r = 0.19) and their mothers' BMD (r = 0.44). Multiple regression analysis indicated that only the mothers' BMD remained an independent predictor of bone mass. Mother-daughter correlations were also observed for body weight (r = 0.24), height (r = 0.39), BMI (r = 0.29), dietary calcium intake (r = 0.20), and calcium (r = 0.20) or vitamin D (r = 0.25) intakes from dairy products. Hence, these observations support the evidence that mothers' BMD is the strongest predictor of bone mass of young women in their third decade.     

Association between current nutrient intakes and bone mineral density at calcaneus in pre- and postmenopausal Japanese women.

The association between nutrient intake and bone mineral density (BMD) at calcaneus was cross-sectionally examined in 243 pre- (aged 29-60 years) and 137 postmenopausal (aged 39-60 years) Japanese women who participated in a BMD checkup and have kept a stable diet for at least 3 previous years and had no dietary therapy. Nutrient intakes were assessed with a self-administered diet history questionnaire. BMD at calcaneus was measured with dual-energy X-ray absorptiometry. In a multiple regression analysis with adjustments for nondietary factors such as age, body height, fat body weight, nonfat body weight, and number of deliveries, calcium (p<0.01) and niacin (p<0.05) significantly and positively, and phosphorus and dietary fiber (p<0.05 for both) significantly and negatively correlated in premenopausal women, and only potassium (p<0.05) significantly and positively correlated in postmenopausal women with BMD. The results suggest that several nutrients correlate with BMD, and the associations differ depending on menopausal status. epidemiology, diet, nutrients, bone mineral density. Japanese women     

Effect of habitual dietary calcium intake on calcium supplementation in 12-14-y-old girls

BACKGROUND: There is no agreement on how much calcium young girls need for optimal bone mineralization. OBJECTIVE: We evaluated whether the effect of calcium supplementation on whole-body bone mineral accretion depends on habitual calcium intake. DESIGN: This was a randomized, double-blind, placebo-controlled, 1-y calcium intervention study of girls aged 12-14 y selected from a larger group according to habitual calcium intake: subgroup A (n = 60) habitually consumed 1000-1307 mg/d (40th-60th percentile), and subgroup B (n = 53) habitually consumed <713 mg/d (<20th percentile). The girls from each subgroup were randomly assigned to receive either 500 mg Ca/d or placebo. Whole-body bone mineral content (BMC), bone area (BA), bone mineral density (BMD), and BMC adjusted for BA, height, and weight (size-adjusted BMC) were measured at baseline and after 1 y. RESULTS: There was no significant effect modification of baseline habitual calcium intake on the relation between calcium supplementation and height, weight, BMC, size-adjusted BMC, BA, BMD, or alkaline phosphatase. Calcium supplementation had an effect on BMD (0.8%; P = 0.049) and tended to show signs of an effect on size-adjusted BMC (0.5%; P = 0.08). CONCLUSION: A modest effect of calcium supplementation on BMD was shown. However, the effect was independent of habitual calcium intake.     

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。     

Bone mineral status in adolescent girls: effects of eating disorders and exercise.

PURPOSE: To compare whole-body, lumbar, total spine, and pelvis bone mineral density (BMD), body mass index (BMI), body composition, energy expenditure for physical activity, and dietary intake of adolescents, aged 16-22 years. METHODS: Three study groups included 25 girls with histories of eating disorderd, 25 girls with no histories of eating diso rders who exercised < or = 7 hours/week, and 15 girls with no history of eating disorders who exercised > 7 hours/week. Bone mineral density was measured by dual-energy x-ray absorptiometry (DEXA), body composition by bioelectric impedance and DEXA, energy expenditure by Personal Activity Computer, nutrient intake by 4-day dietary recalls/records, and BMI by measures of height/weight. General linear models, LSM +/- SEM, Student's t-tests, and correlation analyses were used to determine group differences. RESULTS: No significant differences in whole-body, spinal, and pelvis BMD were found among the three groups. Mean body fat (percent) was significantly higher (p =.0001) for the group with histories of eating disorders than other groups. Dietary intakes of adolescents with histories of eating disorders were significantly lower for energy (p =.0001), fat (p =.0001), calcium (p =.0007), vitamin D (p =.0180), and zinc (p =.0057) than those without eating disorder histories who exercised 相似文献   

Calcium intake influences the association of protein intake with rates of bone loss in elderly men and women

BACKGROUND: There is currently no consensus on the effect of dietary protein intake on the skeleton, but there is some indication that low calcium intakes adversely influence the effect of dietary protein on fracture risk. OBJECTIVE: The objective of the present study was to determine whether supplemental calcium citrate malate and vitamin D influence any associations between protein intake and change in bone mineral density (BMD). DESIGN: Associations between protein intake and change in BMD were examined in 342 healthy men and women (aged > or = 65 y) who had completed a 3-y, randomized, placebo-controlled trial of calcium and vitamin D supplementation. Protein intake was assessed at the midpoint of the study with the use of a food-frequency questionnaire and BMD was assessed every 6 mo by dual-energy X-ray absorptiometry. RESULTS: The mean (+/-SD) protein intake of all subjects was 79.1 +/- 25.6 g/d and the mean total calcium intakes of the supplemented and placebo groups were 1346 +/- 358 and 871 +/- 413 mg/d, respectively. Higher protein intake was significantly associated with a favorable 3-y change in total-body BMD in the supplemented group (in a model containing terms for age, sex, weight, total energy intake, and dietary calcium intake) but not in the placebo group. The pattern of change in femoral neck BMD with increasing protein intake in the supplemented group was similar to that for the total body. CONCLUSION: Increasing protein intake may have a favorable effect on change in BMD in elderly subjects supplemented with calcium citrate malate and vitamin D.     

Effect of calcium supplementation on bone mineral accretion in gambian children accustomed to a low-calcium diet

BACKGROUND: Rural Gambian children have poor growth, delayed puberty, a low bone mineral content, and a low calcium intake. OBJECTIVE: We investigated the effect of a calcium supplement on bone mineral accretion in rural Gambian children. DESIGN: A randomized, double-blind, placebo-controlled study was conducted in 160 children (80 boys, 80 girls) aged 8.3-11.9 y. Bone mineral content (BMC), bone mineral density (BMD), and BMC adjusted for bone width, body weight, and height (size-adjusted BMC) were measured at the midshaft and distal radius. Each child received either 1000 mg Ca/d (as calcium carbonate) or a placebo 5 d/wk for 12 mo. Supplementation increased calcium intake from 342 to 1056 mg/d (8.6 to 26.4 mmol/d). RESULTS: Calcium supplementation resulted in a higher BMC, BMD, and size-adjusted BMC (&xmacr; difference +/- SE): midshaft radius-BMC (3.0 +/- 1.4%; P = 0.034), BMD (4.5 +/- 0.9%; P 相似文献   

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.     

四川省阿坝州藏羌和汉族儿童少年骨量影响因素分析

目的了解四川省阿坝州藏、羌、汉族儿童少年骨量的影响因素,为制定学生营养政策、预防骨质疏松提供基础资料和科学依据。方法采用问卷调查方式,收集四川省阿坝藏羌自治州1821名7～18岁藏、汉、羌族男、女生的膳食营养素摄入和体力活动情况,测量身高和体重;采用生物电阻抗仪测定体成分,并用双能X线吸收仪（DEXA）测定前臂近端1/3处和远端1/10处骨矿物含量（BMC）和骨面积（BA）。结果多元线性回归分析发现,瘦体重对前臂远端1/10处和前臂近端1/3处的BMD和BMC的变异贡献要高于其他因素,其标准偏回归系数分别为0.567,0.687,0.346和0.482;藏族、钙摄入量、体力活动能量消耗等因素对前臂远端1/10处BMD和BMC的作用有统计学意义,其标准化回归系数分别为0.094和0.061,0.034和0.022,0.034和0.024。结论体重（尤其是瘦体重）是儿童少年骨量的主要影响因素,民族、膳食营养素摄入、体力活动因素也是影响儿童少年骨量的重要因素。     

The relationship between habitual dietary phosphorus and calcium intake, and bone mineral density in young Japanese women: a cross-sectional study

Phosphorus and calcium are essential for bone health. There is a concern that a low calcium/phosphorus intake ratio resulting from low calcium intake coupled with high phosphorus intake may have a negative effect on bone mineral status, especially in Western countries. The objective of this study was to examine cross-sectionally the influence of habitual phosphorus and calcium intake and the calcium/phosphorus intake ratio on the bone mineral density (BMD) in 441 young Japanese women (aged 18-22) whose calcium/phosphorus intake ratio was assumed to be lower than young Western women. We also ascertained the relationship between dietary intake and serum or urinary measurements of phosphorus and calcium. Parathyroid hormone (PTH) and 25-hydroxy vitamin D (25(OH)D) were also examined for 214 of the 441 subjects. Phosphorus and calcium intake and the calcium/phosphorus intake ratio had significant positive correlations with urinary phosphorus. Calcium intake and the calcium/phosphorus intake ratio independently had positive and significant associations with BMD in the distal radius adjusted for postmenarcheal age, body mass index, and physical activity. There were no significant associations with BMD in the lumbar spine and femoral neck. These results indicate that in young Japanese women, phosphorus intake did not have a significantly negative effect on bone mineral density, and calcium intake and calcium/phosphorus intake ratio had a small but significant association only in a site-specific manner with BMD.     

Protein intake: effects on bone mineral density and the rate of bone loss in elderly women

BACKGROUND: The role of dietary protein in bone metabolism is controversial. OBJECTIVE: We investigated the associations of dietary protein intake with baseline bone mineral density (BMD) and the rate of bone loss over 3 y in postmenopausal elderly women. DESIGN: Women aged 65-77 y (n = 489) were enrolled in an osteoporosis intervention trial. We studied the associations of protein intake as a percentage of energy with baseline BMD and the rate of bone loss in 96 women in the placebo group (n = 96). We also examined the effect of the interaction of dietary calcium intake with protein intake on BMD. RESULTS: In the cross-sectional study, a higher intake of protein was associated with higher BMD. BMD was significantly higher (P < 0.05) in the spine (7%), midradius (6%), and total body (5%) in subjects in the highest quartile of protein intake than in those in the lower 2 quartiles. This positive association was seen in women with calcium intakes > 408 mg/d. There was no significant effect of protein intake on hip BMD. In the longitudinal study of the placebo group, there was no association between protein intake and the rate of bone loss. CONCLUSIONS: The highest quartile of protein intake (: 72 g/d) was associated with higher BMD in elderly women at baseline only when the calcium intake exceeded 408 mg/d. In the longitudinal study, no association was seen between protein intake and the rate of bone loss, perhaps because the sample size was too small or the follow-up period of 3 y was not long enough to detect changes.     

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。     

Calcium intake and bone mass development among Israeli adolescent girls.

OBJECTIVE: To determine the possible relationship between food and life style habits and bone health in adolescent Israeli females. METHODS: 2,000 adolescent Israeli Jewish and Arab high-school girls (mean age 14.5) completed a semi-quantitative food frequency questionnaire and a personal history questionnaire. 27 food components were calculated for each subject. Bone mineral content and density were determined for 112 subjects with calcium intake below 800 mg/day. RESULTS: Average calcium intake was found to be 1,260 mg/day, but 20% of all girls had a calcium intake below 800 mg/day. All low-energy diets were very low in calcium, as mean calcium intake per 1,000 calories was 411 128 grams. A large percentage of diets with less than 800 mg calcium were also deficient in phosphorus (95.2%), magnesium (84.8%). iron (90.5%) and zinc (100%). Due to differences in food sources. Jewish girls had more phosphorus in their diet, but less magnesium and iron compared to Arab girls. Calcium and zinc deficiencies in Jewish and Arab diets were similar. A negative correlation was found between body mass index (BMI) and age at menarche for all girls in the study. Bone mineral density (BMD) measured for girls with calcium intake below 800 mg/day distributed normally around the average when compared to age matched controls despite their low calcium intake. There was a strong positive correlation between BMD and bone mineral content (BMC) at all sites and body weights. CONCLUSIONS: Low calcium intake, other nutritional deficiencies and delayed menarche due to low-energy diet in the growing period and in adolescence may prevent the formation of healthy bones. There is no evidence of lower bone mass among the low calcium intake group in the study population at this stage. It remains to be documented if the window of opportunity for optimal bone accretion for this group will be missed in the future. possibly leading to increased risk of osteoporosis.     

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     

Intake of fermented soybeans, natto, is associated with reduced bone loss in postmenopausal women: Japanese Population-Based Osteoporosis (JPOS) Study

Japanese fermented soybeans (natto in Japanese), which contain a large amount of menaquinone-7, may help prevent the development of osteoporosis. We assessed the possibility of an association between habitual natto intake and bone mineral density (BMD) and BMD change over time in healthy Japanese women who participated in a large representative cohort study (Japanese Population-based Osteoporosis Study: JPOS study). The BMD was measured at the spine, hip, and forearm in 944 women (20-79 y old) at baseline and at a follow-up conducted 3 y later. Dietary natto intake was assessed by a FFQ on both occasions. Additional covariates including age, height, weight, lifestyle factors, dietary calcium intake, and the intake of other soybean products, were also measured. The total hip BMD at baseline increased (P for trend = 0.0034) with increasing habitual natto intake in the postmenopausal women, although this was not the case at other skeletal sites. There were significant positive associations between natto intake and the rates of changes in BMD at the femoral neck (P < 0.0001) and at the distal third of the radius (P = 0.0002) in the postmenopausal women. The association in the femoral neck persisted even after adjusting for covariates. No significant association was observed between the intake of tofu or other soybean products and the rate of BMD change in the postmenopausal women. Natto intake may help prevent postmenopausal bone loss through the effects of menaquinone 7 or bioavailable isoflavones, which are more abundant in natto than in other soybean products.