Calcium plays an important role in various physiological activities of the human body, and long-term insufficient or excessive intake of calcium will have a negative impact on the body's health. Existing data show that insufficient dietary calcium intake is closely related to bone health, but the non-bone effects are not clear. Increasing dietary calcium and supplementing calcium (with or without vitamin D) have a certain beneficial effect on the bone mineral density and its peak of adolescents and can delay the bone loss of the elderly, but it can't improve the height and bone mineral density of adults and fracture in the elderly. This article introduces the physiological functions of calcium, dietary sources, human intake, and methods for formulating recommended amounts, and summarizes the relationship between calcium and health effects. It also recommends that when formulating the reference intake of dietary calcium for Chinese residents, more consideration should be given to the data and information of the Chinese population, combined with the characteristics of Chinese residents' genetics, absorption and metabolism.
Adolescent ; Adult ; Aged ; Bone Density ; Calcium ; Calcium, Dietary/analysis* ; China/epidemiology* ; Humans ; Vitamin D

OBJECTIVETo understand the daily calcium intake, food sources and the trends among Chinese children and adolescents aged 4 to 17 years from 1991 to 2009.

METHODSConsecutive 3-day-24-hour dietary recall data from the seven waves of the China Health and Nutrition Survey(CHNS)was used to describe the status and trends of daily calcium intake and related food sources.

RESULTSBetween 1991 and 2009, the daily intake of calcium in Chinese children and adolescents showed an increasing trend. In 2009, the average intakes of calcium in Chinese boys and girls were 311.2 mg/d and 294.6 mg/d, respectively. 81.5%-87.6% of boys and 87.0%-91.0% of girls had their calcium intakes less than half of the recommended amount of adequate intakes. Only 0.2%-0.8% of boys and 0.1%-0.8% of girls had their calcium intakes equal or higher than the recommended amount of adequate intakes. The sources of dietary calcium were mainly from vegetables, legumes, cereals and milk products for Chinese children and adolescents, accounting for more than 70% of the average daily intakes.

CONCLUSIONDuring the past two decades, the dietary calcium intake of Chinese children and adolescents still remained at lower level, suggesting that the optimal food sources of calcium were under-consumed.

Adolescent ; Calcium, Dietary ; analysis ; Child ; Child, Preschool ; China ; epidemiology ; Cross-Sectional Studies ; Feeding Behavior ; Female ; Humans ; Male ; Nutrition Surveys

BACKGROUND: Inadequate calcium and vitamin D intake is a possible risk factor of osteoporosis. Our purposes were to estimate calcium and vitamin D intake in women with osteoporotic fractures, to determine associated factors for low calcium and vitamin D intake, and to evaluate the effects of calcium and vitamin D intake on bone mineral density (BMD). METHODS: This is a multicenter, hospital-based, and cross-sectional study involving 277 women with osteoporotic fractures. Dietary calcium and vitamin D intake were evaluated using the Korean Calcium Assessment Tool (KCAT) self-reported questionnaire. BMD was measured by dual energy X-ray absorptiometry (DXA) in the lumbar spine and femoral neck. RESULTS: Average daily calcium and vitamin D intake was 503.7±274.7 mg and 7.5±12.6 µg, respectively. Patients with low calcium intake had less family history of osteoporosis and were older. There was a negative correlation between age and calcium intake (r=-0.14; P=0.019). In multivariate analysis, calcium intake showed a positive correlation with BMD of femoral neck (β=0.0005, P=0.021). CONCLUSIONS: About 80% of patients with osteoporotic fracture had calcium and vitamin D intake below the recommended dietary intake. Low calcium intake was associated with no family history of osteoporosis and older age. Dietary calcium intake showed positive effect on BMD.
Absorptiometry, Photon ; Bone Density ; Calcium ; Calcium, Dietary* ; Cross-Sectional Studies ; Female ; Femur Neck ; Humans ; Multivariate Analysis ; Osteoporosis ; Osteoporotic Fractures* ; Risk Factors ; Spine ; Vitamin D* ; Vitamins*

In the Chinese national nutrition surveys, fortified foods were not investigated separately from the base diet, and the contribution of fortified foods to micronutrients intake is not very clear. This study investigated the diet, including fortified foods and food supplements, of urban pregnant women and analyzed the intake of calcium, iron, and zinc to assess the corresponding contributions of fortified foods, food supplements, and the base diet. The results demonstrated that the base diet was the major source of calcium, iron, and zinc, and was recommended to be the first choice for micronutrients intake. Furthermore, consumption of fortified foods and food supplements offered effective approaches to improve the dietary intake of calcium, iron, and zinc in Chinese urban pregnant women.
Adult ; Calcium, Dietary ; analysis ; metabolism ; China ; Cities ; Diet ; Dietary Supplements ; analysis ; Female ; Food, Fortified ; analysis ; Health Knowledge, Attitudes, Practice ; Humans ; Iron, Dietary ; analysis ; metabolism ; Micronutrients ; analysis ; metabolism ; Minerals ; analysis ; Pregnancy ; Socioeconomic Factors ; Urban Health ; statistics & numerical data ; Young Adult ; Zinc ; analysis ; metabolism

OBJECTIVETo investigate the age, gender and region specified milk consumption and its changing trends of Chinese 18 - 44 years old adults in 9 provinces (autonomous region) from 1991 to 2006.

METHODSThe data of 18 - 44 aged old adults investigated in Chinese Health and Nutrition Survey from 1991 to 2006 in 9 provinces (autonomous region) were utilized. The numbers of the subjects selected in 1991, 1993, 1997, 2000, 2004 and 2006 were 5593, 5491, 5334, 4188 and 3908, respectively. Changes of the percentage of milk consumption, average intake of daily milk and dietary calcium intake were analyzed across different groups of gender, income levels, and areas.

RESULTSThere was an increasing trend in the percentage of milk consumption and daily intake of milk from 1991 to 2006. The average percentage of Chinese adult milk consumption went up from 2.2% (123/5593) in 1991 to 7.6% (297/3908) in 2006 (Z = -22.16, P < 0.01). Specifically, urban adult and rural adult showed significant increase in the percentages from 9.7% (80/823) to 23.7% (112/472) (Z = -12.81, P < 0.01) and 0.1% (2/2937) to 1.8% (36/1987) (Z = -9.21, P < 0.01) respectively. Percentages of adult who ever drank milk at top income level and bottom income level increased from 4.7% (95/2006) to 14.6% (200/1373) (Z = -17.36, P < 0.01) and from 0.1% (2/1748) to 2.4% (28/1171) (Z = -9.58, P < 0.01), respectively. Meanwhile, the average daily intake of milk increased from (3.6 ± 24.6) g/d in 1991 to (11.8 ± 51.4) g/d in 2006 (F = 67.07, P < 0.01). The daily milk consumption among top income level adults and bottom income level adults increased from (8.5 ± 50.9) g/d to (23.1 ± 71.5) g/d and from (0.2 ± 6.5) g/d to (3.3 ± 23.5) g/d (F = 13.90, P < 0.01), respectively. From 1991 to 2006, milk consumers significantly promoted their percentage of achieving the Chinese dietary reference intake on calcium (800 mg/d) from 6.5% (8/123) to 12.8% (38/297) (Z = -1.67, P < 0.05), whereas this percentage increased from 1.6% (38/5470) to 3.6% (130/3611) among milk non-consumers (Z = -5.66, P < 0.01).

CONCLUSIONChinese adult milk intake still remains in quite low level, and the situation of milk consumption among rural adults requires further promotion.

Adolescent ; Adult ; Animals ; Asian Continental Ancestry Group ; Calcium, Dietary ; analysis ; China ; Feeding Behavior ; Female ; Humans ; Male ; Milk ; Nutrition Surveys ; Rural Population ; Suburban Population ; Urban Population ; Young Adult

OBJECTIVE: The purpose of this study was to evaluate the effects of soybean intake on bone mineral density and bone turnover markers in postmenopausal rural Korean women. METHOD: This study was carried out during nine months from Oct. 25 2004 to Aug. 31 2005. The subjects of this study were female patients over 50 living in rural areas diagnosed with osteoporosis. There were 18 women in the experimental group and 20 in the control group. In this study, the experimental group received 100 mg of isoflavone (soybean) and calcium 1,500 mg for nine months while the control group received 1,500mg of calcium only. RESULTS: After the soybean intake, the change of bone mineral density between the experimental group and control group was statistically significant. However, the bone turnover markers of osteocalcin and deoxypyridinoline between the experimental group and control group were not significantly different statistically. In the Pearson Correlation between bone mineral density and bone turnover markers, the osteocalcin and deoxypyridinoline of the experimental group had a positive correlation, and osteocalcin and DPD/osteocalcin ratio had anegative correlation. In the control group, osteocalcin and DPD/osteocalcin ratio had a negative correlation. CONCLUSIONS: This result showed that soybean intake changed bone mineral density in postmenopausal woman.
Aged ; Amino Acids/analysis ; Biological Markers/analysis ; Bone Density/*drug effects ; Bone Resorption ; Calcium/*therapeutic use ; Dietary Supplements ; Female ; Humans ; Isoflavones/*therapeutic use ; Middle Aged ; Osteocalcin/analysis ; Osteoporosis, Postmenopausal/*drug therapy ; Women's Health

BACKGROUND: The evidence for a protective effect of calcium on bone mineral density is controversial. Despite this conflicting evidence an assessment of dietary calcium is often included in the clinical evaluation of osteoporosis risk. The purpose of this study was to assess the relationships between calcium intake and bone mineral density(BMD) in postmenopausal women. METHODS: The subjects consisted of 143 postmenopausal women over 40 years old who visited the Department of Family Medicine and Orthopedic Surgery in Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea from June 1997 to September 1998. They were divided into three groups such as osteoporosis, osteopenia and control groups according to the level of BMD. The BMD of the lumbar was measured by dual-energy X-ray absorptiometry. Dietary assessment was performed by semi-quantitative food frequency questionnaire. RESULTS: Total calcium intakes were directly proportional to the BMD among three groups : they were 385.5+/-298.8mg/d, 438.3+/-216.5mg/d and 548.3+/-405.3mg/d in osteoporosis, osteopenia and control groups, respectively. Multivariate analysis, which was adjusted for age, place of residence in teenage, education, body mass index, exercise, muscular strength and energy intake, was performed between osteoporosis and control groups. As a result, the odds ratio of the highest 25% vs the bottom 25% of calcium distribution by milk consumption was 0.037(95% CI 0.002~0.891). In comparison of milk consumption at least once per day with that of less than 1 time per week, the odds ratio was 0.081(95% CI 0.008~0.793). CONCLUSIONS: Levels of BMD in postmenopausal women are associated with amount and frequency of milk consumption. Therefore, more than 100mg/d of calcium intake - that is, at least a half glass of milk a day - should be recommended in postmenopausal women in order to prevent osteoporosis.
Absorptiometry, Photon ; Academic Medical Centers ; Adult ; Body Mass Index ; Bone Density* ; Bone Diseases, Metabolic ; Calcium* ; Calcium, Dietary ; Chungcheongnam-do ; Education ; Energy Intake ; Female ; Glass ; Humans ; Korea ; Milk ; Multivariate Analysis ; Odds Ratio ; Orthopedics ; Osteoporosis ; Seoul ; Ulsan ; Surveys and Questionnaires

BACKGROUND/OBJECTIVES: This study was performed to measure fat-soluble vitamins and minerals in breast milk of Korean lactating mothers who exclusively breastfed their babies. SUBJECTS/METHODS: Breast milk samples were collected from 334 mothers. Concentrations of retinol and α-tocopherol were analyzed by high performance liquid chromatography ultraviolet spectrometry while concentrations of minerals were measured by inductively coupled plasma optical emission spectrometry. RESULTS: Retinol and α-tocopherol contents of breast milk were 39.58 ± 19.64 µg/dL and 0.23 ± 0.13 mg/dL, respectively. Average sodium, potassium, calcium, phosphorus, and magnesium levels in breast milk were 11.11 ± 5.16, 38.56 ± 9.01, 27.87 ± 6.10, 13.56 ± 3.30, and 3.05 ± 0.65 mg/dL, respectively. Contents of trace elements such as iron, zinc, copper, and manganese were 40.26 ± 46.21, 98.40 ± 62.47, 24.09 ± 9.03, and 0.90 ± 1.63 µg/dL, respectively. Fat-soluble vitamin concentration was positively correlated with total fat in milk samples, but no significant differences were observed in levels of retinol, α-tocopherol, or minerals based on whether or not lactating women were taking dietary supplements. CONCLUSIONS: Micronutrient contents of breast milk samples from Korean lactating women were comparable to those of other nations. Retinol and α-tocopherol levels were correlated and also with total fat in breast milk.
Breast* ; Calcium ; Chromatography, Liquid ; Copper ; Dietary Supplements ; Fats ; Female ; Humans ; Infant* ; Iron ; Korea* ; Magnesium ; Manganese ; Micronutrients ; Milk ; Milk, Human* ; Minerals* ; Miners* ; Mothers ; Phosphorus ; Plasma ; Potassium ; Sodium ; Spectrum Analysis ; Trace Elements ; Vitamin A* ; Vitamins ; Zinc

BACKGROUNDOptimal mineral intakes are important for infant growth and development. However, data on mineral compositions of breast milk in Chinese women are scarce, and most were acquired before 1990. The objectives of this study were three-fold: (1) to investigate the mineral compositions of Chinese healthy mothers' breast milk in different lactation stages; (2) to explore correlations among mineral concentrations in breast milk; and (3) to explore the associated factors affecting mineral compositions in breast milk.

METHODSThe inductively coupled plasma mass spectrometry (ICP-MS) was used to analyze mineral concentrations in breast-milk of 444 healthy lactating women from three cities in China. A questionnaire was used to survey socio-demographic characteristics and pregnancy history. Food intakes by lactating women were measured using both food frequency questionnaire and one cycle of 24-hour dietary recall.

RESULTSMineral compositions of breast milk varied in different regions. Concentrations of most minerals were higher in the first one or two months of lactation, and then decreased with time, except for magnesium and iron. Inter-mineral correlations existed among several minerals. The calcium-to-phosphorus ratio was above 2:1 in each lactation stage. Women with caesarean section had higher concentration of iodine in the transitional milk (349.9 µg/kg) compared to women with natural delivery (237.5 µg/kg, P < 0.001). Dietary mineral intakes, supplements, food intake frequencies in the recent 6 months, maternal age and maternal BMI did not show significant correlations with concentrations of milk minerals (all P > 0.05).

CONCLUSIONSMilk minerals decreased with time, and changed most rapidly in the first one or two months of lactation. Caesarean section might affect the iodine level in transitional milk.

Adult ; Calcium ; administration & dosage ; metabolism ; Dietary Supplements ; Female ; Humans ; Iodine ; administration & dosage ; metabolism ; Lactation ; metabolism ; Mass Spectrometry ; Milk, Human ; chemistry ; metabolism ; Minerals ; administration & dosage ; analysis ; Phosphorus ; administration & dosage ; metabolism ; Pregnancy

BACKGROUND/AIMS: To prevent hypocalcemia after parathyroidectomy (PTX), parenteral calcium is required in addition to oral calcitriol and calcium. After switching to oral calcium, patients can be discharged from the hospital. The aim of this study was to analyze the clinical characteristics and outcomes of PTX performed at a single Korean center and to investigate the associated laboratory factors used to analyze the total amount of postoperative calcium required. METHODS: We enrolled 91 hemodialysis patients undergoing PTX from November 2003 to December 2011. We collected clinical and laboratory data preoperatively, 12 and 48 hours postoperatively, at discharge, and 3 and 6 months postoperatively. RESULTS: In total, 59 patients underwent PTX with autotransplantation (AT), 6 underwent total PTX without AT, 11 underwent subtotal PTX, and 15 underwent limited PTX. Total PTX without AT showed the lowest recurrence rate. At all postoperative time points, the mean levels of serum calcium, phosphorus, and intact parathyroid hormone (iPTH) decreased significantly, compared with preoperative levels; however, alkaline phosphatase (ALP) increased significantly from 48 hours postoperatively to discharge (p < 0.001). On multiple linear regression analysis, the total amount of injected calcium during hospitalization showed a significant correlation with preoperative ALP (p < 0.001), preoperative iPTH (p = 0.037), and Deltaphosphorus at 48 hours (p < 0.001). We developed an equation for estimating the total calcium requirement after PTX. CONCLUSIONS: Preoperative ALP, preoperative iPTH, and Deltaphosphorus at 48 hours may be significant factors in estimating the postoperative calcium requirement. The formula for postoperative calcium requirement after PTX may help to predict the duration of postoperative hospitalization.
Administration, Intravenous ; Administration, Oral ; Adult ; Aged ; Biomarkers/blood ; Calcium/blood ; Calcium Carbonate/*administration & dosage ; Calcium Compounds/*administration & dosage ; Calcium Gluconate/*administration & dosage ; *Decision Support Techniques ; *Dietary Supplements ; Female ; Humans ; Hyperparathyroidism, Secondary/blood/diagnosis/*surgery ; Hypocalcemia/diagnosis/etiology/*prevention & control ; Lactates/*administration & dosage ; Linear Models ; Male ; Middle Aged ; Models, Biological ; Multivariate Analysis ; Parathyroid Hormone/blood ; Parathyroidectomy/*adverse effects ; Phosphorus/blood ; Recurrence ; Republic of Korea ; Retrospective Studies ; Risk Factors ; Time Factors ; Treatment Outcome ; Young Adult