Vitamin D Status and Associated Factors of Older Adults in the Cross-Sectional 2015-2017 Survey.

Vitamin D is beneficial for maintaining good health; however, there is a lack of nationally representative data reported, particularly in older adults. To better understand the nutritional status of vitamin D and its influencing factors on Chinese older adults, we adopted stratified random sampling to select serum samples originating from the Chronic Disease and Nutritional Survey Biobank of Chinese Residents in 2015-2017. Serum 25-hydroxyvitamin D (25(OH)D) concentrations were determined by enzyme-linked immunoassay. The OR and PR of associated factors for vitamin D deficiency and insufficiency were calculated. In the study, a total of 6273 participants were included. Median serum 25(OH)D concentration was 18.48 (13.27-24.71) ng/mL. The overall rate of vitamin D deficiency and insufficiency was 58.27% (<20 ng/mL), and the VDD rate was 22.17%, which is worse than 5 years ago by nearly 20%. The likelihood of vitamin D deficiency and insufficiency is increased in women, people aged and above 70 years, ethnic minorities, people living in urban areas, midlands, or western areas, warm or medium temperate zones, with middle school and above education level, and people with abdominal obesity and anemia would increase the possibility of vitamin D deficiency and insufficiency with latitude having the greatest impact on vitamin D deficiency and insufficiency. Overall, vitamin D deficiency and insufficiency are very common in Chinese older adults. They should be encouraged to improve their vitamin D nutritional status through enough sunshine exposure and increasing vitamin D intake through diet or supplements.

Free and bioavailable 25-hydroxyvitamin D thresholds for bone metabolism and their associations with metabolic syndrome in Chinese women of childbearing age.

Objective: The free hormone hypothesis suggests that free and bioavailable 25-hydroxyvitamin D [25(OH)D] may better reflect vitamin D bioactivity. This study aimed to determine the free and bioavailable 25(OH)D characteristics, estimate their thresholds based on parathyroid hormone (PTH) and bone turnover markers (BTMs), assess their associations with the risk of metabolic syndrome (MetS), and evaluate their potential advantages. Methods: A cross-sectional study was conducted using a nationally representative database (n = 1,505, female, 18-45 years). Serum total 25(OH)D, vitamin D-binding protein, albumin, PTH, and BTMs [osteocalcin, ß-CrossLaps of type 1 collagen containing cross-linked C-telopeptide (ß-CTX), and procollagen type 1 N-terminal propeptide (P1NP)] were measured. Free 25(OH)D and bioavailable 25(OH)D were calculated. The threshold associations of 25(OH)D with PTH and BTMs were analyzed. The relationship between 25(OH)D and MetS risk was examined. An intervention study was then performed in 39 women (18-47 years) to assess the associations of increasing 25(OH)D with PTH and BTMs after vitamin D supplementation. Results: In the cross-sectional study, the three forms of 25(OH)D were found to have similar distribution characteristics. Free and bioavailable 25(OH)D correlated well with total 25(OH)D. Significant total 25(OH)D cutoffs were observed for PTH (14.19 ng/mL and 18.03 ng/mL), osteocalcin (15.14 ng/mL), ß-CTX (14.79 ng/mL), and P1NP (15.08 ng/mL). Free and bioavailable 25(OH)D cutoffs were only found for P1NP (3.47 pg/mL and 1.66 ng/mL, respectively). A total 25(OH)D of <15.14 ng/mL was marginally associated with a higher risk of reduced high-density lipoprotein cholesterol (HDL-C) [odd ratios (OR) = 1.371 (0.991-1.899)]. The ORs of higher versus lower free and bioavailable 25(OH)D levels for reduced HDL-C were 0.770 (0.621-0.956) and 0.772 (0.622-0.958), respectively. The results of the intervention study indicated that PTH and BTMs responded more sensitively to total 25(OH)D than to free or bioavailable 25(OH)D. Conclusion: Free and bioavailable 25(OH)D only had a threshold effect on P1NP. The active 25(OH)D thresholds could be used for risk assessment of reduced HDL-C. However, no superiority of free or bioavailable 25(OH)D was found based on the response of PTH and BTMs to changes in 25(OH)D in Chinese women of childbearing age following vitamin D supplementation. Clinical trial registration: http://www.chictr.org.cn, ChiCTR2200058290.

[Plasma selenium level and its influencing factors in Chinese child-bearing-aged women in 2015].

OBJECTIVE: To assess the plasma selenium(Se) level of child-bearing-aged women and discuss the influence factor for low-Se level. METHODS: Using the muti-stage stratified and population proportional cluster random sampling method, 1881 child-bearing-aged women aged 18 to 44 years were selected from China Adult Chronic Disease and Nutrition Surveillance(2015) Data. The basic information of the subjects was collected by unified electronic questionnaires and equipments were used for field survey, measurement and record. Plasma Se concentration was detected by inductively coupled plasma mass spectrometry. Plasma low-Se level were assessed using lower limit of plasma/serum Se established by the Mayo Clinic Laboratory and our laboratory, respectively. Influence factors of low-Se level were analyzed by the multivariate logistic regression model. RESULTS: The M(P25, P75) plasma Se concentration for Chinese child-bearing-aged women was 89.52(74.21, 105.03)µg/L. Nationality, location, urban-rural type and education level difference had influence on plasma Se level in this population(P<0.05). According to the lower limit of plasma/serum Se concentration established by the Mayo clinical laboratories(<70 µg/L) and our laboratories(<73.81 µg/L), the low-Se rate were 20.47% and 24.51%, respectively. There were significantly differences in low-Se rate among nationality, location, urban-rural type, education level and marital status(P<0.05). The multivariate logistic regression model showed that location and urban-rural type had significant effects on low-Se rate of child-bearing-aged women(P<0.05). CONCLUSION: The plasma low-Se rate of Chinese women of childbearing age is relatively high and higher prevalence low-Se was found in western and central regions and rural areas in China.

Re-exploration of dietary iodine intake in Chinese adult males using a modified iodine balance study.

There is still controversy about optimal dietary iodine intake as the Universal Salt Iodization policy enforcement in China. A modified iodine balance study was thus conducted to explore the suitable iodine intake in Chinese adult males using the iodine overflow hypothesis. In this study, thirty-eight apparently healthy males (19·1 (sd 0·6) years) were recruited and provided with designed diets. After the 14-d iodine depletion, daily iodine intake gradually increased in the 30-d iodine supplementation, consisting of six stages and each of 5 d. All foods and excreta (urine, faeces) were collected to examine daily iodine intake, iodine excretion and the changes of iodine increment in relation to those values at stage 1. The dose-response associations of iodine intake increment with excretion increment were fitted by the mixed effects models, as well as with retention increment. Daily iodine intake and excretion were 16·3 and 54·3 µg/d at stage 1, and iodine intake increment increased from 11·2 µg/d at stage 2 to 118·0 µg/d at stage 6, while excretion increment elevated from 21·5 to 95·0 µg/d. A zero iodine balance was dynamically achieved as 48·0 µg/d of iodine intake. The estimated average requirement and recommended nutrient intake were severally 48·0 and 67·2 µg/d, which could be corresponded to a daily iodine intake of 0·74 and 1·04 µg/kg per d. The results of our study indicate that roughly half of current iodine intakes recommendation could be enough in Chinese adult males, which would be beneficial for the revision of dietary reference intakes.

Vitamin D Status for Chinese Children and Adolescents in CNNHS 2016-2017.

Vitamin D is very important in maintaining children's bone health because of its regulatory role in calcium and phosphate metabolism. To better understand vitamin D status and related risk factors of children and adolescents in China, this study analyzed the 25-hydroxyvitamin-D (25(OH)D) concentration of children and adolescents aged 6-17 years in China and assessed the risk factors of vitamin D deficiency and insufficiency. We analyzed the data of 25(OH)D concentration collected from the China National Nutrition and Health Survey of Children and Lactating Mothers in 2016-2017 (CNNHS 2016-2017). The age, sex, region type, ethnicities, season, weight and height were recorded, measured by unified questionnaire, equipment and standards. The concentration of 25(OH)D was detected by LC-MS/MS. A total of 64,391 participants from the cross-sectional study of CNNHS in 2016-2017 were included in this study. The median serum 25(OH)D concentration was 17.70 (13.20-22.68) ng/mL, 18.70 (14.10-23.80) ng/mL in boys and 16.60 (12.40-21.40) ng/mL in girls. The total prevalence rate of vitamin D deficiency and insufficiency was 65.98% when the cut-off was 20 ng/mL, 60.42% for boys and 71.99% for girls. According to the results of logistic regression analysis, girls aged above 12 y, living in midlands and northern regions, in spring and winter seasons and with abdominal obesity will have a significantly increased risk of vitamin D deficiency and insufficiency among Chinese children and adolescents. The results showed that vitamin D deficiency and insufficiency are very common among children and adolescents aged 6-17 y in China. They should be encouraged to have more effective sunlight exposure, increased intake of vitamin D from food or supplements in their diet, especially for those aged above 12 y, living in the northern or midlands areas, in spring and winter, and abdominally obese.

Reference Ranges of Selenium in Plasma and Whole Blood for Child-Bearing-Aged Women in China.

Selenium (Se) is a "dual-surface" element. Both Se-deficiency and Se-overload have bad effects on humans. The amount of Se in the blood is a good indicator of Se intake, and there are considerable differences in the reference ranges among different regions and populations. The purpose of this study was to establish the age-specific reference interval of blood Se in healthy child-bearing-aged women in China. A total of 187 healthy women aged 18-45 years old were enrolled with strict inclusion criteria from the China Adult Chronic Disease and Nutrition Surveillance (2015 CACDNS) database to establish the reference interval of Se. Plasma and whole-blood Se were detected by inductively coupled plasma mass spectrometry (ICP-MS). The reference range (RR) estimated as P2.5-P97.5 percentiles (geometric mean) was 73.81-140.75 (100.94) µg/L and P2.5-P97.5 percentiles (median) 81.06-164.75 (121.05) µg/L for plasma and whole-blood Se, respectively. The proposed RR of plasma Se in this study was used to evaluate the Se nutritional status of a representative sample of 1950 women of child-bearing age who were randomly selected from 2015 CACDNS. The proportion of Se level lower than P2.5 cut-off value was 24.05%, and there were 5.08% child-bearing-aged women with plasma Se higher than the upper limit of RR. Women in the western and rural areas tend to have lower Se levels.

[Plasma proteomic analysis of diabetes improvement by vitamin D supplementation].

OBJECTIVE: To analyze the effect of vitamin D supplementation on the improvement of diabetes mellitus based on plasma proteomics. METHODS: Five-week-old SPF spontaneously obese rats with type 2 diabetes were randomly divided into a diabetic group and a diabetic vitamin D intervention group, and the control group was Zucker lean rats. The fasting blood glucose of the rats in each group was compared with that of the diabetic vitamin D group, and the plasma proteins of the rats in each group were compared by quantitative analysis of the high-resolution mass spectrometry system iTRAQ, and KEGG signaling pathway analysis was performed. RESULTS: The fasting blood glucose of rats in the diabetic vitamin D intervention group was significantly lower than that of the diabetic group, and the proteins that were differentially expressed in the diabetic vitamin D intervention group were significantly improved. KEGG signaling pathway analysis revealed that the differential proteins in the diabetic group were mainly distributed among enzymes, exosomal proteins, and peptidases and inhibitors, and that the number of differences in these three classes of proteins was significantly reduced in the diabetic intervention group. CONCLUSION: Vitamin D supplementation can improve the differential expression of fasting glucose and plasma proteins in the diabetic rats.

Serum Vitamin A Nutritional Status of Children and Adolescents Aged 6-17 Years - China, 2016-2017.

SUMMARY: What is already known on this topic? Vitamin A deficiency (VAD) in children is still a global public health problem, which needs continuous monitoring and timely intervention.What is added by this report? Using surveillance data from China Nutrition and Health Surveillance of Children and Lactating Mothers in 2016-2017, the prevalence of VAD and marginal deficiency was 0.96% and 14.71%, respectively. The vitamin A nutritional status of children and adolescents from urban areas and those aged 12-17 years were better than those from rural areas and aged 6-11 years.What are the implications for public health practice? Marginal VAD was a major form of VAD in Chinese children. The monitoring of vitamin A status in key populations should be continuously strengthened, and the public should be encouraged to consume foods rich in vitamin A or vitamin A supplements.

Vitamin D Nutritional Status of Chinese Pregnant Women, Comparing the Chinese National Nutrition Surveillance (CNHS) 2015-2017 with CNHS 2010-2012.

Optimal vitamin D (vitD) status is beneficial for both pregnant women and their newborns. The aim of this study was to evaluate the vitamin D status of Chinese pregnant women in the latest China Nutrition and Health Surveillance (CNHS) 2015-2017, analyze the risk factors of vitamin D deficiency (VDD), and compare them with those in CNHS 2010-2012. Serum 25 hydroxyvitamin D (25(OH)D) was measured by ELISA method. City type, district, latitude, location, age, vitamin D supplements intake, education, marital status, annual family income, etc., were recorded. The median 25(OH)D concentration was 13.02 (10.17-17.01) ng/mL in 2015-2017, and 15.48 (11.89-20.09) ng/mL in 2010-2012. The vitamin D sufficient rate was only 12.57% in 2015-2017, comparing to 25.17% in 2010-2012. The risk factors of vitamin D inadequacy (25(OH)D < 20 ng/mL) in 2015-2017 were not exactly consistent with that in 2010-2012. The risk factors included season of spring (p < 0.0001) and winter (p < 0.001), subtropical (p < 0.001), median (p < 0.0001) and warm temperate zones (p < 0.0001), the western (p = 0.027) and the central areas (p = 0.041), while vitD supplements intake (p = 0.021) was a protective factor in pregnant women. In conclusion, vitD inadequacy is very common among Chinese pregnant women. We encourage pregnant women to take more effective sunlight and proper vitD supplements, especially for those from the subtropical, warm and medium temperate zones, the western and the central, and in the seasons of spring and winter.

Physiologic requirement for iron in pregnant women, assessed using the stable isotope tracer technique.

BACKGROUND: Knowledge of the physiologic requirement for iron, the core index for the formulation of a dietary reference intake (DRI), is of great importance for the health of a pregnant woman and her fetus, and can help a mother accurately plan her iron supplementation. However, direct measurements of the physiologic requirement for iron during pregnancy are still lacking. METHOD: Eleven women of reproductive age from Hebei Province, China, who planned to become pregnant in the near future, were enrolled between January and March 2015 and included in the final analysis. Subjects participated in a 2-week metabolic trial in which they consumed 50 mg of the stable isotope 58Fe, and were then followed for ~ 2 years. The abundance of 58Fe and the total iron concentration in the circulation were measured using Multi-collector Inductively-Coupled Plasma Mass Spectrometry and Atomic Absorption Spectroscopy, respectively. The physiologic requirement for iron during pregnancy was then calculated by the formula derived from our previously published work. RESULTS: The mean physiologic requirement for iron in the 11 subjects, across their entire pregnancies, was 3.05 mg.d- 1 in total and 44.0 µg.kg- 1.d- 1 after adjustment for body mass. The physiologic requirements for iron in the first, second, and third trimesters were 2.04 mg.d- 1, 3.26 mg.d- 1, and 4.13 mg.d- 1, respectively. When adjusted for body mass, the physiologic requirements for iron in different trimesters were 32.3 µg.kg- 1.d- 1, 46.9 µg.kg- 1.d- 1, and 55.7 µg.kg- 1.d- 1, respectively. CONCLUSION: We preliminarily explored the physiologic requirement for iron in pregnant women. The data demonstrated that pregnant women needed about twice iron than non-pregnant women. This research may be helpful for the design of future studies and the modification of iron DRIs. TRIAL REGISTRATION: ChiCTR, ChiCTR-OCH-14004302. Registered 14 February 2014, http://www.chictr.org.cn/showproj.aspx?proj=5267.

The Chinese Children and Families Cohort Study: The Nutrition, Physical Activity, and Ultraviolet Radiation Data Collection.

This article reports the study design, methodological issues and early results of a pilot study testing methods for collecting nutrition, physical activity, and ultraviolet (UV) radiation exposure data in a groundbreaking study in China. Epidemiological studies suggest that exposures across the entire life course, including in utero, early childhood, and adolescence, may be important in the etiology of adult cancers and other chronic diseases. The Chinese Children and Families Cohort Study intends to follow-up subjects from the 1993 to 1995 Community Intervention Program of folic acid supplementation for the prevention of neural tube defects. This cohort is unique in that only folic acid exposure during pregnancy varies between groups as other supplements were not available, and there were nutrient deficiencies in the populations. Prior to launching a large-scale follow-up effort, a pilot study was conducted to assess the feasibility of recontacting original study participants to collect extensive diet, physical activity, and UV radiation exposure data in this population. The pilot study included 92 mothers and 184 adolescent children aged 14 to 17 years from 1 urban and 1 rural Community Intervention Program site. Subjects completed a Food Frequency Questionnaire, a 3-day food record, a physical activity questionnaire, a 3-day sun exposure diary together with 3 days of personal UV dosimetry, and 7 days of pedometry measurements and provided blood, saliva, and toenail samples. Grip strength and body composition measurements were taken, and ambient solar UV radiation was monitored in both study sites. While most of the assessments were successful, future studies would likely require different dietary intake instruments. The purpose of this report is to describe the study design and methodological issues emerging from this pilot work relevant for the follow-up of this large birth cohort.

Proteins enriched in charged amino acids control the formation and stabilization of selenium nanoparticles in Comamonas testosteroni S44.

Elemental selenium nanoparticles (SeNPs) are useful in medicine, environmental remediation and in material science. Biosynthesized SeNPs (BioSeNPs) by bacteria are cheap, eco-friendly and have a lower cytotoxicity in comparison with chemically synthesized ones. Organic matters were found to cap on the surface of BioSeNPs, but the functions were still not entirely clear. The purified BioSeNPs were coated in a thick layer of organic substrates observed by transmission electron microscopy (TEM). Fourier Transform Infrared (FT-IR) and quantitative detection of the coating agents showed that one gram of purified BioSeNPs bound 1069 mg proteins, 23 mg carbohydrates and only very limited amounts of lipids. Proteomics of BioSeNPs showed more than 800 proteins bound to BioSeNPs. Proteins enriched in charged amino acids are the major factor thought to govern the formation process and stabilization of BioSeNPs in bacteria. In view of the results reported here, a schematic model for the molecular mechanism of BioSeNPs formation in bacteria is proposed. These findings are helpful for the artificial green synthesis of stable SeNPs under specific condition and guiding the surface modification of SeNPs for medicine application.

Vitamin D Nutritional Status and its Related Factors for Chinese Children and Adolescents in 2010-2012.

Vitamin D plays a critical role in calcium and phosphate metabolism and helps maintain skeletal integrity in childhood, yet vitamin D status in Chinese children and adolescents is not well documented. The aim of this study was to assess the vitamin D status and analyze the risk factors for vitamin D deficiency in Chinese children and adolescents aged 6-17 years. Serum 25 hydroxyvitamin D (25(OH)D) was measured with a radioimmunoassay kit in 15,000 children and adolescent participants in the Chinese national nutrition and health survey (CNNHS) 2010-2012. Age, gender, region type, ethnicity, outdoor time, and vitamin D supplementation were recorded in unified design questionnaires. The season was recorded by the date of blood taken; location was divided into north and south by China's Qinling Mountains and Huaihe River; and ambient ultraviolet B (UVB) radiation level was classified according to the corresponding dose of each participant living area from National Aeronautics and Space Administration data. 14,473 participants from the cross-sectional study of CNNHS 2010-2012 were included in this study. The median serum 25(OH)D concentration was 48.2 (35.4-63.4) nmol/L, and the concentration for males was 50.0 (36.5-65.7) nmol/L, which was statistically higher than that of females (46.7 (34.4-60.9) nmol/L) (P < 0.001). The general prevalence of vitamin D deficiency was 53.2%; 50.0% for males and 56.5% for females at the cut-off 50 nmol/L. According to the results of the log-binomial regression analysis, vitamin D deficiency in Chinese children and adolescents was specifically related to female gender (P < 0.0001), to ages 12-14 years (P < 0.0001) and 15-17 years (P < 0.0001), living in large cities (P < 0.0001) or ordinary rural areas (P < 0.0001), low ambient UVB levels (P < 0.0001) and medium ambient UVB levels (P < 0.0001), spring (P < 0.0001), autumn (P < 0.0001) and winter seasons (P < 0.0001). The data showed that vitamin D deficiency was very common among children and adolescents aged 6-17 years in China. Effective sun exposure should be encouraged in both genders aged 6-17 years, dietary vitamin D and vitamin D supplements are also recommended, especially in the seasons of spring and winter.

Vitamin D status among the elderly Chinese population: a cross-sectional analysis of the 2010-2013 China national nutrition and health survey (CNNHS).

BACKGROUND: Vitamin D inadequacy is common among the elderly, especially within the Asian population. The vitamin D status among healthy adults in the elderly Chinese population was evaluated. METHODS: A total of 6014 healthy adults aged 60 years or older (2948 men, 3066 women) participated in this descriptive cross-sectional analysis. Possible predictors of vitamin D inadequacy were evaluated via multiple logistic regression analyses. RESULTS: The median serum 25-hydroxyvitamin D (25(OH)D) levels were 61.0 nmol/l (interquartile range (IQR) 44.3-80.6, range 5.1-154.5) for men and 53.7 nmol/l (IQR 38.8-71.0, range 6.0-190.0) for women, with 34.1% (95% confidence interval (CI) 32.4-35.8) of men and 44.0% (95% CI 42.2-45.8) of women presenting vitamin D inadequacy (25(OH)D <50 nmol/l). According to the multivariate logistic regression analyses, vitamin D inadequacy was positively correlated with female gender (P <0.0001), underweight (P = 0.0259), the spring season (P <0.0001), low ambient UVB levels (P <0.0001) and living in large cities (P = 0.0026). For men, vitamin D inadequacy was positively correlated with the spring season (P = 0.0015), low ambient UVB levels (P <0.0001) and living in large cities (P = 0.0022); for women, vitamin D inadequacy was positively correlated with the spring season (P = 0.0005) and low ambient UVB levels (P <.0001). CONCLUSIONS: Vitamin D inadequacy is prevalent among the elderly population in China. Because residing in regions with low ambient UVB levels increases the risk of vitamin D inadequacy both for men and women, vitamin D supplementation and sensible sun exposure should be encouraged, especially during the cooler seasons. Further studies are required to determine the optimal vitamin D intake and sun exposure levels to maintain sufficient vitamin D levels in the elderly Chinese population.

[Gender differences in iron status in infants 4 and 6 months of age].

OBJECTIVE: To study gender differences in different measures of iron status in infants aged 4 and 6 months old. METHODS: Term delivery pregnant women with normal iron status were recruit with informed consent. Infants with normal birth weight were selected and exclusive breastfeeding were required. All infants were randomly assigned into one control group and one iron supplement group at 4 months old. The latter group were given a daily dose of iron supplement corresponding to 1 mg/kg body weight of elemental iron from 4 to 6 month. At 4 and 6 months old, vein blood were sampled to analyze hemoglobin (Hb), mean cell volume (MCV), serum ferritin (SF), and soluble transferrin receptors (sTfR) and the growth indices were measured. RESULTS: Data of infants at 4 months old (n = 178) and 6 months old (n = 85) were collected. At 4 months old, male infants had significantly lower MCV and SF and higher sTfR, male infants had lower Hb but with no significant difference. 6 months old, the trends of differences stayed the same as at 4 months old, and MCV remained significant. CONCLUSION: Male infants may have a higher risk to develop iron deficiency. Male infants may have a higher risk to develop iron deficiency. There needs to be respective diagnostical cut-off values and dietary iron requirement for male and female infants. At the same time, correct feeding is necessary.

Polyphenolics composition of the leaves of Zanthoxylum bungeanum Maxim. grown in Hebei, China, and their radical scavenging activities.

High performance liquid chromatography coupled with tandem mass spectrometry with electrospray ionization and negative ion detection (HPLC-ESI-MS/MS) was used to identify the polyphenols from the leaves of a traditional vegetable and spice, Zanthoxylum bungeanum Maxim., in China by comparison of the retention times and mass spectral fragment with standard substances or related literature. A phenolic acid glucoside, two acids, and eight flavonoids were determined including vanillic acid-4-glucoside (22.75 µg/g, dry weight of leaves), quinic acid (58.58 µg/g), chlorogenic acid (2515.96 µg/g), epicatechin (77.80 µg/g), 5-feruloyquinic acid (16.63 µg/g), syringetin-3-glucoside (103.23 µg/g), rutin (89.41 µg/g), hyperoside (886.36 µg/g), quercetin-3-arabinoside (118.75 µg/g), quercitrin (645.82 µg/g), and isorhamnetin-3-glucoside (104.27 µg/g). The obtained polyphenols show good radical scavenging activities in DPPH and superoxide anion. Through the intracellular antioxidation assay, the result shows that the polyphenols could reduce the ROS in HT-29 cells without cell toxicity.

[The influence of preventive iron supplementation to iron nutritional status in breastfed infants].

OBJECTIVE: To analyze the effects to iron status who were given preventive iron supplements for two months from when they were breast-fed to four-month-old. METHODS: A total of 123 infants in four-month-old age who were breast-fed were randomly divided into iron supplementation group (63 cases) and control group (60 cases), iron supplementation group was supplied with low-dose iron (1 mg×kg⁻¹×d⁻¹) for two months with no intervention for control group. Blood samples were collected to test C reactive protein and iron status indicators in six-month-old age group infants, and the growth indices were measured and compared on the gender difference of iron status at and 6 months. RESULTS: After 2 months of low-dose iron supplementation, the hemoglobin of iron supplementation group (26 cases) increased about 5.5 g/L while the control group (34 cases) increases about 0.0 g/L (median), 95% confidence intervals were -7.0 - 13.0 g/L and -9.0 - 15.0 g/L, respectively. The hemoglobin increase of iron supplementation group was higher than the control group, the difference was statistically significant (u = -2.326, P < 0.05). The other iron nutritional status and the growth did not show any significant difference between iron supplementation group and control group (P > 0.05). At age 6 month, the MCV of the boys were (75.89 ± 3.34) fl, while the girls were (77.20 ± 3.17) fl. The boys had lower values of MCV than the girls, and the gender difference was statistically significant (t = 4.73, P < 0.05). The other iron nutritional status did not show any significant gender difference (P > 0.05). CONCLUSION: Low-dose iron supplementation of breast-fed infants at 4-month-old can increase the hemoglobin level when they were 6-month-old, and had no measurable side effect on growth.

Association of estrogen receptor-alpha gene Pvull polymorphisms with the effect of calcium supplementation on skeletal development in Chinese pubertal girls.

OBJECTIVE: To investigate the association of estrogen receptor alpha (ER-alpha) PvuII polymorphisms with the effect of calcium supplementation on bone development in Chinese pubertal girls, and to study the importance of calcium supplementation by maximizing the peak bone mass at their pubertal stage for bone development and osteoporosis prevention and the role of estrogen in regulating bone mass. METHODS: Ninety-four pubertal girls were recruited in the study and divided into two groups and three sub-groups according to the ER-alpha PvuII polymorphisms. One year before and after calcium supplementation, bone mineral density (BMD) was measured by DEXA, while BGP, BAP, TRACP5b, and 25-OH-VitD(3), as well as estrogen were detected by ELISA. Analysis of covariance was used to examine the effect of ER-alpha polymorphisms on bone development. RESULTS: The absolute increase and percentage change of BGP were significantly higher in the supplemented group than in the control group (P<0.05). In the intervened group, The increase and percentage change of the total body and radio distal 1/3 BMD were higher in PP than in PP genotype (P<0.05), and the increase of BAP in Pp was also higher than PP in the same group (P<0.05). CONCLUSION: PP genotype shows a better response to calcium supplementation than the other PvuII polymorphisms.

Studies on zinc bioavailability from a representative diet in Chinese urban women of childbearing age using a double label stable isotope technique.

The objectives of the study were to determine dietary zinc bioavailability by using a double label stable isotope technique, and to identify the zinc content and levels of some possible factors which may affect zinc utilization in a typical representative Chinese urban diet. Twenty urban women of childbearing age were fed a diet extrinsically labeled with 67Zn and received intravenous (i.v.) injections of 70Zn. Fecal monitoring, urine monitoring and chemical balance technique were used simultaneously for comparisons. Isotopic enrichment in feces and urine after oral and i.v. administration of stable zinc isotopes was measured to determine the ways of zinc absorption. The mean (+/-SD) zinc intake from the representative Chinese diet was 10.22+/-0.80 mg/day, which is lower than the reference nutrient intake (RNI) level (11.5 mg/day), and mainly came from the subsidiary foods (63%). The mean dietary Fe/Zn weight was 1.1+/-0.1. The phytate/zinc molar ratio in the diet was about 3:1. The phytic acidxCa/zinc molar ratio in the diet was about 45:1. The apparent and true absorption rates of 67Zn were 36.2+/-9.7% and 38.2+/-10.1%, respectively, which were higher than the apparent absorption determined by balance technique (29.7+/-10.6%). The mean fractional absorption (FA) determined in urine was 35.7+/-13.3. In conclusion, the subsidiary food is the main source of dietary zinc in this typical diet. The extrinsic labeling technique by use of stable isotopes was more reliable and accurate to determine zinc absorption. Moreover, the double isotopic tracer ratio (DITR) technique applied to urine samples was a more practical and valuable way to evaluate zinc absorption than other methods. It can be speculated that iron and phytic acid might not be the main inhibitors in the representative Chinese diet.