[Blood cadmium level and the change of cadmium exposure risk in Chinese urban school-age children in 2002 and 2012]

OBJECTIVE

To investigate the blood cadmium concentrations and the related change in Chinese urban children derived from the China Nutrition and Health Survey 2002 and 2012(CNHS 2002 and CNHS 2012).

METHODS

The Chinese urban children aged 6-11 years were selected according to gender, age and regional distribution using the multi-stage stratified cluster random sampling method, as well as the corresponding whole blood samples. The blood cadmium concentration was carefully determined by the quadrupole inductively coupled plasma mass spectrometry(ICP-MS) and the percentage of blood cadmium over 2 μg/L was subsequently estimated. In addition, the upper limit values of the 95%CI of the 95th percentiles of available blood cadmium data was assessed as the threshold of cadmium exposure.

RESULTS

Totally, 2182 Chinese urban children were included, and of these, 1036 children were from the CNHS 2002 and 1146 children were from the CNHS 2012. From the CNHS 2002 to the CNHS 2012, the median blood cadmium concentration was increased from 0.28 μg/L to 0.95 μg/L, and the percentage of blood cadmium with over 2 μg/L was elevated from 1.45% to 10.47%. In addition, the new estimated threshold of blood cadmium was ascended from 1.24 μg/L up to 2.89 μg/L.

CONCLUSION

The risk of cadmium exposure in Chinese urban children aged 6-11 years was increasingly aggravated from the CHNS 2002 to the CNHS 2012.

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.

The Time Trend of Blood Lead and Cadmium Levels in Rural Chinese Children: China Nutrition and Health Survey 2002 and 2012

This study was to investigate blood lead (Pb) and cadmium (Cd) levels and time trend in rural Chinese children derived from the China Nutrition and Health Survey 2002 and 2012 (CNHS 2002, CNHS 2012). In total, 1698 and 1581 of rural Chinese children were selected from the CNHS 2002 and the CNHS 2012 databases, respectively. The blood Pb and Cd levels were determined by inductively coupled plasma mass spectrometer (ICP-MS), whilst the prevalence of blood Pb levels >5 µg/dL and blood Cd levels >0.5 µg/L and the corresponding reference values (RV₉₅s: the upper limit of 95% confidence interval of 95th percentile) were together calculated. From the CNHS 2002 to the CNHS 2012, median concentrations in blood were severally decreased from 6.3 to 3.1 µg/dL for Pb and from 0.64 to 0.39 µg/L for Cd. The prevalence of blood Pb levels >5 µg/dL had decreased from 63.6 to 14.2%, together with blood Cd levels >0.5 µg/L prevalence from 62.7 to 33.5%, respectively. The RV₉₅s of blood Pb and Cd levels were 15.2 µg/dL and 1.54 µg/L in the CNHS 2002, as well as 6.3 µg/dL and 1.12 µg/L in the CNHS 2012. In conclusion, blood Pb and Cd levels had been obviously improved in rural Chinese children during the past 10 years. However, the risks of Pb and Cd exposure are still serious and required to have continuous health monitoring and evaluation, even call for greater collaboration of the government and society.

Exploration of the lower threshold of iodine intake in Southern Chinese young adults based on ‘overflow theory’ in an iodine balance study

Background

Appropriate iodine intake for adults is essential to reduce the prevalence of thyroid diseases, but there is little research data on iodine requirement of Chinese population. This study aimed to explore the iodine requirement of young adults to maintain a healthy status based on ‘overflow theory’.

Methods

Iodine-balance experiment has been performed in this project. We conducted an 18-day study consisted of a 6-day acclimation period and 3 consecutive experimental stages in 37 Chinese healthy young adults (23 female and 14 male). Each stage was consumed for 4 days. Strictly-controlled low-iodine intake diets were provided for adults in the first period, an egg or 125mL milk was added in the second and third period, respectively. The dietary samples, 24-h urine specimens and faeces of volunteers were collected daily for assessment of iodine intake and excretion in volunteers.

Results

Mean values of iodine intake (22.7±3.6, 35.1±3.7, and 52.2±3.8μg/d), excretion (64.7±13.9, 62.3±12.6, and 94.3±14.5μg/d) and iodine balance (-35.2±19.5, -21.0±19.8, and -33.5±26.9μg/d) were significantly different among three periods for male (P<0.001 for all); mean values of iodine intake (16.6±3.1, 29.7±2.7, and 48.0±2.7μg/d), and excretion (47.0±9.9, 55.5±8.1, and 75.7±12.4μg/d) were significantly different among three periods for female (P < 0.001 for all). No significant difference was observed among the 3 periods for female in the iodine balance (-30.5±9.3, -25.9±7.3, and -27.6±12.1μg/d). The linear regression equation of iodine excretion on iodine intake was Y=0.979X+37.04 (male) and Y=0.895X+31.48 (female). Compared with stage 2, iodine excretion increments in stage 3 had exceeded the iodine intake increment for men. The ratio of increment was 1.675 for male when the average iodine intake was 52.2μg/d in stage 3. When the iodine excretion increment equaled to the iodine intake increment, the daily iodine intake of men was 47.0μg.

Conclusion

We have evaluated the iodine requirement of young adults in southern China based on overflow theory. Our results indicate the lower limit of iodine requirement for Chinese young men is 47.0μg/d. The trial was registered at www.chictr.org.cn as ChiCTR1800014877.

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

Physiological requirements for iron in women of reproductive age assessed by the stable isotope tracer technique

Background

Iron nutrition is important for the health of women of reproductive age, and defining the physiologic requirement for iron can help them accurately plan the iron intake. However, research on the physiologic requirement for iron in women is insufficient worldwide. This study aimed to further improve the methodology and get more precise data for the physiological requirements for iron in women of reproductive age on the basis of our previous study.

Method

Sixty-one women of reproductive age who had not been pregnant before and during the whole study were included from Hebei province, China in 2015. Each subject participated in a 2-week metabolic trial with consuming 50 mg of the stable isotope ⁵⁸Fe, and were then followed for ~ 800 days. 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. The physiologic requirement for iron in women of reproductive age was then calculated.

Results

The average iron circulation rate was 80.4%, and the steady period started from about 1 year. The average physiological requirement for iron of 21 subjects obtained by formula calculation was 1.55 mg/d and 23.63 μg.kg^− 1.d^− 1 after adjustment for body mass, and that of 33 subjects obtained by linear regression was 1.29 mg/d, 20.98 μg.kg^− 1.d^− 1 after adjustment for body mass. The results by two methods showed no significant difference. The EAR and RNI calculated from this results was 11–13 mg/d and 15–18 mg/d, respectively, both of which were slightly lower than the recommended value in Chinese Dietary Reference Intake (2013).

Conclusion

The physiological requirements for iron in women of reproductive age were in accordance with other studies, while the EAR and RNI calculated from which were slightly lower than Chinese present recommended value.

Trial registration

ChiCTR, ChiCTR-OCH-14004302. Registered 14 February 2014, http://www.chictr.org.cn/enindex.aspx

Electronic supplementary material

The online version of this article (10.1186/s12986-019-0384-1) contains supplementary material, which is available to authorized users.

The dietary transition and its association with cardiometabolic mortality among Chinese adults, 1982-2012: a cross-sectional population-based study

BACKGROUND

Few studies have used nationally representative data to describe dietary trends and the related cardiometabolic mortality burden in China. Thus, we aimed to characterise the trends in disease-related dietary factors as well as their associated disease burden among Chinese adults from 1982 to 2012.

METHODS

For this cross-sectional population-based study, we analysed a nationally representative sample of 204 802 adults aged 20 years or older, using data from the 1982, 1992, 2002, and 2010-12 China National Nutrition Surveys (CNNS). We did a comparative risk assessment, in which the effects of suboptimal intakes of 12 dietary factors, individually and collectively, on cardiometabolic mortality were estimated by calculating the population attributable fraction (PAF) to estimate the proportional reduction in cardiometabolic deaths that would occur if exposure to each dietary risk factor was reduced to an alternative optimal level.

FINDINGS

The overall PAF of mortality from cardiovascular disease and type 2 diabetes that was associated with suboptimal dietary quality was 62·2% in 1982, 57·9% in 1992, 56·2% in 2002, and 51·0% in 2010-12, which accounted for 21·6% of total mortality in China in 1982, 16·6% in 1992, 17·6% in 2002, and 20·8% in 2010-12. The estimated number of cardiometabolic deaths associated with suboptimal dietary intakes was 1·07 million in 1982, 0·93 million in 1992, 1·18 million in 2002, and 1·51 million in 2010-12. Of all 12 dietary factors examined, high sodium intake (17·3%), low fruit consumption (11·5%), and low marine omega-3 fatty acids (9·7%) were associated with the largest numbers of estimated cardiometabolic deaths in 2010-12.

INTERPRETATION

We observed an improvement in several dietary factors in China in the past few decades. However, current intakes of these dietary factors remain suboptimal. Poor diet quality is estimated to be associated with a substantial proportion of deaths from heart disease, stroke, and type 2 diabetes in China.

FUNDING

Ministry of Health, China, and Ministry of Science and Technology, China.

Bioavailability and incorporation of nonheme iron from a representative Chinese diet in young urban Chinese women

BACKGROUND AND OBJECTIVES

This study assessed the bioavailability and biological incorporation of nonheme iron from staple food diets in healthy young urban Chinese women and determined the relevant effects of typical regional patterns of staple foods in South and North China.

METHODS AND STUDY DESIGN

Twenty-two young urban Chinese women aged 20-23 years were enrolled and randomly allocated to two groups, with rice (rice group) and steamed buns (steamed buns group) as the staple food, respectively. Each participant received three meals daily containing approximately 3.25 mg of stable 57FeSO4 for 2 consecutive days, along with daily intravenous injection of approximately 2.0 mg of 58FeSO4. Nonheme iron absorption and infused iron incorporation rates were assayed.

RESULTS

In all participants, the rice group, and the buns group, nonheme iron intake was 7.2±1.6, 5.9±0.6, and 8.4±1.2 mg, respectively; mean 57FeSO4 absorption rate was 22.2%±9.6%, 22.2%±10.6%, and 22.2%±8.9%, respectively; and the mean infused 58FeSO4 incorporation rate was 91.6%±8.2%, 93%±7.3%, and 90%±9.1%, respectively. No substantial differences existed in the nonheme iron intakes and the 57FeSO4 absorption and 58FeSO4 incorporation rates between the rice and buns groups (all p>0.05).

CONCLUSIONS

The bioavailability and incorporation rates of nonheme iron from representative comprehensive Chinese diets in healthy young urban Chinese women were evaluated. Our results can facilitate the establishment of dietary reference intake for iron in Chinese women.

Prevalence of Anemia in Chinese Children and Adolescents and Its Associated Factors

In this study, we assessed the hemoglobin levels and anemia status of Chinese children and adolescents from the Chinese National Nutrition and Health Survey (CNNHS) in 2010⁻2012 and analyzed the factors associated with anemia. The hemoglobin concentration and prevalence of anemia for children and adolescents aged 6⁻17 years from both CNNHS 2010⁻2012 and CNNHS 2002 were analyzed. Multi-variable logistic regression analysis was used to assess the factors associated with anemia. The mean hemoglobin concentration increased among Chinese children and adolescents, from 135.2 ± 13.9g/L in CNNHS 2002 to 141.2 ± 15.8 g/L in CNNHS 2010⁻2012, with the prevalence of anemia decreasing from 12.6% to 6.6% (p<0.0001). Anemia was specifically related to girls (p < 0.0001);children aged 6⁻8 years (p = 0.0175), 12⁻14 years (p = 0.0007), and 15⁻17 years (p < 0.0001);ordinary rural areas (p = 0.0009) and poor rural areas (p < 0.0001);spring (p < 0.0001), autumn (p < 0.0001), and winter (p < 0.0001);underweight individuals (p < 0.0001); and an annual average income per capita of less than 20,000 RMB (p < 0.0001).The prevalence of anemia in Chinese children and adolescents has improved significantly in comparison to 10 years prior; however, it remains a public health problem in this population. Further research is required to understand the determinants of iron status, which could then lead to strategies to alleviate iron deficiency for Chinese children and adolescents, especially for girls, those living in rural areas, underweight individuals, and those with a low family income.

Basal energy expenditure, resting energy expenditure and one metabolic equivalent (1 MET) values for young Chinese adults with different body weights

BACKGROUND AND OBJECTIVES

Accurately assessing energy expenditure (EE) of people with different body weight is essential to facilitate weight management. The aim of this study was to measure basal energy expenditure (BEE), resting energy expenditure (REE) and to explore the true 1 MET value for young Chinese adults with different body weight.

METHODS AND STUDY DESIGN

A total of 251 young Chinese adults were divided into three groups: the normal weight group, the overweight group and the obese group. Their BEE, REE and 1 MET values were measured by Cortex Metamax 3B (MM3B). Multiple linear regressions and correlation analysis were used to examine factors that influence EE in Chinese population.

RESULTS

The mean measured BEE and REE of young Chinese adults with normal weight, overweight and obesity was 1429, 1609, 1778 kcal/day and 1522, 1712, 1885 kcal/day, respectively. The EE per kilogram body weight decreased with the increasing body weight. The mean oxygen consumption in the three group was 3.78, 3.47, 3.21 mL/kg/min respectively. There was no significant difference in BEE and REE after adjustment for fat-free mass (FFM). The significant influencing factors were body mass index (BMI) and sex in BEE, FFM and BMI in REE in Chinese population.

CONCLUSIONS

BEE and REE were significantly different for different body weights while these differences disappeared after adjustment for FFM, and people with different body weights may have different 1 MET values. Further studies should be conducted to obtain more accurate daily energy requirement and 1MET value for specific Chinese populations.

[Thyroid function for Chinese pregnant women in 2010-2012]

OBJECTIVE

To evaluate thyroid function and iodine nutritional status for pregnant women from various regions of China by determining plasma levels of thyrotrophin( TSH), free triiodothyronine( FT3), and free thyroxine( FT4).

METHODS

Plasma samples were obtained from pregnant women that participated in the 2010-2012 China National Nutrition and Health Survey. Plasma levels of TSH, FT3, and FT4 were determined by using an automated chemiluminescence immunoassay analyzer. Thyroid function was evaluated according to the determined levels.

RESULTS

A total of 877 plasma samples collected from pregnant women residing in different regions of China wereanalyzed for levels of TSH, FT3, and FT4. The median TSH levels detected in the first, second, and third trimesters of pregnancy were 1. 56, 1. 84, and 1. 89 m IU/L, respectively. The median FT4 levels were 17. 21, 16. 29 and 16. 35 pmol/L, respectively. The median FT3 levels were 4. 70, 4. 39 and 4. 18 pmol/L, respectively. The rate of normal thyroid function for this cohort was 78. 1%, and for the pregnant women that resided in large cities the rate was 71. 2%. The most common type of abnormal thyroid function that was detected was subclinical hypothyroidism. It had an overall incidence of10. 5%, and those residing in regions of rural poverty had the highest rate( 14. 5%). The normal rate of thyroid function for adult pregnant women at the end of the trimester( 28-40 weeks) during pregnancy was significantly lower than that of the pregnant women in the first and second trimester.

CONCLUSION

The rate of normal thyroid function in pregnant women is low( less than 80%). Subclinical hypothyroidism is the main type of thyroid dysfunction during pregnancy. It should be continued to pay attention to the relationship between the high incidence of subclinical hypothyroidism and iodine nutritional status of pregnant women, especially subclinical hypothyroidism caused by insufficient iodine intake.

[Assessment of iodine nutritional status for pregnant women using adjusted urine creatinine from spot and 24-hour urine]

OBJECTIVE

To establish a reliable method of iodine nutritional assessment for pregnant women using the adjusted urinary creatinine of spot urine and 24-hour urine samples.

METHODS

The spot urine in the morning at 8 00-11:30 and the following 24-hour urine samples of pregnant women were collected in Peking Union Medical College Hospital during March to October in 2016. The urinary iodine and urinary creatinine concentrations were determined. The estimated 24-hour urinary iodine excretion( 24-h UIE) was calculated using the urinary iodine/urinary creatinine( UIC/Cr) ratio of spot urine, and 24-hour urinary creatinine excretion( 24-h UCr E).

RESULTS

There was a significant difference in the UIC, UIC/Cr ratio between spot urine and 24-h urine( P <0. 05). The UIC, UIC/Cr ratio of spot urine, and the estimated 24-h UIE all were significantly correlated with the real 24-h UIE( P < 0. 01), especially the estimated 24-h UIE were taking up 70%-80% for the real 24-h UIE in the period of gestation.

CONCLUSION

The UIC, UIC/Cr, and the estimated 24-h UIE cannot directly replace the relevant values derived of the 24-hour urine samples. But the estimated 24-h UIE can reflect the iodine nutritional status of pregnant women in recent days, and the method could be a reliable reference for the iodine nutritional assessment of the pregnant women in practice.

Iron physiological requirements in Chinese adults assessed by the stable isotope labeling technique

Background

Iron is a kind of essential trace mineral in the human body, while the studies on its physiological requirement are very limited recently, especially in China. And most studies were performed with the radioisotope tracer technique, which was harmful to health. This study aimed to first get the value of iron physiological requirements in Chinese adults assessed by the stable isotope labeling technique.

Methods

Forty-four eligible young Chinese healthy adults were randomly recruited from the Bethune Military Medical College (Shijiazhuang, Hebei, China) between January 2010 and March 2011, and 19 subjects were included in the final data analysis. After adaptive diets and observation, subjects received ⁵⁸Fe intravenously. The baseline venous blood sample and general information were collected on day 0. Venous blood samples were also collected on day 14, 30, 60, 100, 120, 150, 240, 330, 425, 515, 605, 767, 1155, respectively. The blood samples were acid digested by a Microwave Digestion System and then analyzed by the MC-ICP-MS and Atomic Absorption Spectroscopy to get the abundance of Fe isotopes and the total iron concentration respectively. The circulation rate (the proportion of blood iron to whole body iron) could be calculated by the intake amount, background content and the peak isotope content. When the abundance changed stably, the iron physiological requirement could be calculated by the iron loss in a period of time.

Results

The abundance of ⁵⁸Fe reached its peak on day 14, and changed stably from day 425. The average circulation rate was 84%, with no significance difference between the 2 genders. The mean iron requirement in females was 1101.68 μg/d, and the mean requirement adjusted by body weight was 20.69 μg/kg.d. For males, the mean iron requirement was 959.9 μg/d, and the requirement adjusted by body weight was 14.04 μg/kg.d.

Conclusion

Our study has obtained the data about the iron physiological requirements of Chinese adults using stable isotope labeling technique, which could provide the basis for adjusting iron DRIs of Chinese people in the future.

Trial registration

The trial was registered at the Chinese Clinical Trial Registry (No: ChiCTR-TRC-09000581).

Modulation of the Fecal Microbiota in Sprague-Dawley Rats Using Genetically Modified and Isogenic Corn Lines

This study investigated the composition and proportions of fecal microbiota in Sprague-Dawley rats after consuming two genetically modified (GM) corn lines in comparison with the isogenic corn and the AIN93G standard feed for 10 weeks using bar-coded 16S rRNA gene sequencing. As a result, GM corn did not significantly alter the overall health and alpha-diversity of fecal microbiota. Fecal microbiota structures could be separated into noncorn and corn but not non-GM and GM corn subgroups. Both non-GM and GM corn caused the increase in bacterial populations related to carbohydrates utilization, such as Lactobacillus, Barnesiella, and Bifidobacterium, and the reduction in potentially pathogenic populations, such as Tannerella and Moraxellaceae. In conclusion, similar effects on the fecal microbiota were observed after consuming a GM- and non-GM-corn-based diet for long periods. Further studies are warranted to elucidate the functional relevance of the changes in the proportions of bacterial populations in these diets.

Assessment of Zinc Status in School-Age Children from Rural Areas in China Nutrition and Health Survey 2002 and 2012

Zinc is an essential trace element for growth and development in children, but zinc deficiency is a serious nutritional problem worldwide. Our study aimed to assess the zinc status of school-age children living in rural areas of China and to examine the change of zinc status based on the China Nutrition and Health Survey 2002 and 2012. We used the probability proportional to size sampling method for subject selection, and a total of 3407 school-age children were included in this study. Zinc status was assessed by three items of indicators recommended by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF), the International Atomic Energy Agency (IAEA), and the International Zinc Nutrition Consultative Group (IZiNCG). The concentration of serum zinc was 718.2 μg/L, and 44.4% of children being zinc deficiency in 2002, while 846.8 μg/L and 10.4% in 2012. Zinc intake was 7.8 mg/day with a 7.6% inadequate zinc intake in 2002, together with 6.9 mg/day and 38.2% in 2012. Height-for-age Z score was -1.06 and 19.1% of children being stunting in 2002, as well as -0.15 and 6.8% in 2012. In conclusion, the zinc status of school-age children living in rural areas of China has been significantly improved in addition to zinc intake over the past 10 years. However, the zinc deficiency still observed in poor rural areas of China in 2012. In addition, we suggested that the zinc bioavailability should be taken into account when assessing zinc status in population.

[Relationship of diabetes mellitus in older Han adults in China with leptin receptor gene rs1137100 and rs1137101 polymorphrism]

OBJECTIVE

To explore the relationship of diabetes in older Han adults with leptin receptor gene rs1137100 and rs1137101 single nucleotide polymorphism( SNP).

METHODS

A total of 511 older Han adults were selected for this study and divided into diabetes and control groups, with 241 and 270 people in each group. The genotypes of rs1137100 and rs1137101 and the allele frequency were determined by Taqman method. The correlations between genotypes of leptin receptor gene SNPs with diabetes wereanalyzed. Blood concentrations of lipids, fasting serum glucose( FBG), leptin and insulin were also measured.

RESULTS

The distribution of GG, GA and AA genotypes in rs1137100 in the diabetes group and the healthy group was 73. 0%, 24. 5%, 2. 5% and 68. 9%, 28. 9%, 2. 2%, respectively. The difference was not significant between the two groups( χ~2= 1. 27, P = 0. 53). There was no significance in the difference of the frequency of "A"allele in rs1137100 in the two groups, with 14. 7% and 16. 7% in each group( χ~2= 0. 72, P = 0. 40). In rs1137101, the distribution of GG, GA and AA genotypes in the diabetes group and the healthy group was 77. 6%, 21. 2%, 1. 2% and 77. 8%, 21. 1%, 1. 1%, respectively. The difference was not significant between the two groups( χ~2= 0. 02, P = 0. 99). There was no significance in the difference of the frequency of"A"allele in rs1137101 in the two groups, with 11. 8% 11. 7% in each group( χ~2=0. 01, P = 0. 94. The Logistic analysis showed that GA and AA genotypes carriers in rs1137100 had similar risk for diabetes when comparing with the GG genotypes( OR =1. 06, 95% CI 0. 34-3. 34, OR = 0. 80, 95% CI 0. 54-1. 19). The GA and AA genotypes carriers in rs1137101 had similar risk for diabetes when comparing with the GG genotypes, and the OR values were 1. 12( 95% CI 0. 22-5. 63) and 1. 01( 95% CI0. 66-1. 54), respectively.

CONCLUSION

The rs1137100 and rs1137101 polymorphism are not significantly associated with the prevalence of diabetes in older Han adults.

[Serum vitamin D levels of Chinese rural women of childbearing age in 2010-2012]

OBJECTIVE

To obtain the serum 25-hydroxyvitamin D status for women of child-bearing age aged 18-44 years from rural areas in China Health and Nutrition Survey2010-2012( CHNS 2010-2012).

METHODS

We randomly selected the 1520 representative women of childbearing age from the 75 monitoring spots derived in the CNHS 2010-2012. The information of study population were collected using questionnaires and the serum 25-hydroxyvitamin D concentration was determinedusing the RIA kits. The vitamin D nutritional status was classified by the standards suggested by the America Endocrine Society. Multiple Logistic regression analysis was explored therelationship between vitamin D status with the potential relevant factors.

RESULTS

The median serum 25-hydroxyvitamin D concentration was 22. 7 ng/m L ranged from 8. 2 to42. 0 ng/m L. The prevalence of vitamin D deficiency was 38. 7%, insufficiently 39. 5%and sufficiently 21. 8%. Multiple Logistic regression analysis showed that nationality, geographical regions and income per capita was the significant.

CONCLUSION

s The nutritional status of vitamin D in women of child bearing-age is not better in the CNHS2010-2012. We suggest that it should be pay more attention on the women of childbearing age for the minority, north China, family income per year between 10000 and 30000 Yuan.

[Vitamin A nutritional status of Chinese rural children and adolescents in 2010-2012]

OBJECTIVE

To analysis the vitamin A nutritional status of 6-to 17-year-old children and adolescents between 2010-2012 in rural China.

METHODS

Based on the China Health and Nutrition Survey 2010-2012 project, the serum vitamin A samples of children and adolescents from survey sites of rural area were selected by random sampling method, and 5888 cases of samples were detected using the high performance liquid chromatography method to evaluate their vitamin A nutritional status.

RESULTS

The serum retinol concentration of children and adolescents in rural area was( 1. 44 ± 0. 58) μmol/L, and were( 1. 40 ± 0. 56) μmol/L in general rural areas and( 1. 46 ± 0. 60) μmol/L in poverty rural areas respectively( t = 1. 88, P < 0. 05). The serum retinol concentration of6-to 11-year-old were( 1. 31 ± 0. 53) μmol/L and( 1. 37 ± 0. 60) μmol/L, and serumretinol concentration of 12-to 17-year-old were( 1. 52 ± 0. 57) μmol/L and( 1. 52 ±0. 60) μmol/L( t = 11. 90 and t = 5. 54, P < 0. 05). The prevalence of vitamin A deficiency was 5. 53%, and were 6. 14% in general rural areas and 4. 55% in poverty rural areas, respectively( P > 0. 05). The prevalence of marginal vitamin A deficiency were 18. 75%, and were 19. 17% in general rural areas and 18. 07% in poverty rural areas, respectively( P > 0. 05).

CONCLUSION

The situation of vitamin A deficiency in rural China are still widespread, the high prevalence of marginal vitamin A deficiency is more prominent.

[Vitamin A nutritional status of Chinese rural fertile women in 2010-2012]

OBJECTIVE

To evaluate nutritional status of vitamin A( VA) among Chinese rural fertile women in 2010-2012.

METHODS

A multi-stage stratified sampling and population proportional stratified random sampling method was used and the participants of rural fertile women who were 18-44 years old and had completed personal information data during the 2010-2012 National Nutrition and Health Survey were included( n = 1279). The level of serum retinol, rate of VA marginal deficiency anddeficiency among the fertile women were analyzed.

RESULTS

In 2010-2012, the P50( P25-P75) level of serum retinol was 1. 63( 1. 28-2. 10) μmol/L for Chinese rural fertile women, 1. 60( 1. 25-2. 05) μmol/L for fertile women from ordinary rural area and1. 70( 1. 32-2. 17) μmol/L for fertile women from poverty rural area. The level of serum retinol of fertile women from poverty rural area was statistically higher than that of ordinary rural area( P = 0. 007). The rate of VA marginal deficiency and deficiency among the Chinese rural fertile women was 9. 46% and 3. 05%, respectively. The rate of VA marginal deficiency and deficiency among the fertile women from ordinary rural area and poverty rural area was 9. 82%, 4. 13%, 9. 03% and 1. 74%, respectively. The rate of VA deficiency among the fertile women from ordinary rural was statistically higher than that of poverty rural( P = 0. 013), but no statistically differences in the rate of VA marginal deficiency were found( P > 0. 05). Moreover, the statistically differences of rate of VA marginal deficiency and deficiency were also observed in the different regions and educational level( only VA deficiency). There were no statistically differences of VA marginal deficiency and deficiency were found in the other variables.

CONCLUSION

The different extent of VA deficiency still present and more popular for the VA marginal deficiency among Chinese fertile women.

[Serum retinol concentrations of Chinese rural elderly residents in 2010-2012]

OBJECTIVE

To assess the vitamin A status of Chinese rural elderly population by analyzing the serum retinol levels of Chinese rural elderly residents in 2010-2012.

METHODS

Data were from the Chinese National Nutrition and Health Survey in2010-2012. Using the multistage stratified cluster sampling method, serum samples from the elderly residents aged above 60 years old( including), were obtained from 45 general rural and 30 poor rural. The basic situation of the survey object was collected by the questionnaire survey. The concentration of serum retinol was determined by high performance liquid chromatography( HPLC). The vitamin A deficiency( VAD) was judged by the related standard recommended by WHO. A total of 2 413 elderly residents were included in the study. The levels of serum retinol and the prevalence of vitamin A deficiency and marginal vitamin A deficiency were also compared.

RESULTS

The level of serum retinol for rural elderly residents was 1. 88( 1. 45-2. 45) μmol/L. The serum retinol level of poor rural resident was( 1. 92( 1. 46-2. 48) μmol/L), which was significant for the ordinary rural residents( 1. 86( 1. 44-2. 41) μmol/L)( χ~2= 5. 1428, P = 0. 0233). The serum retinol of male elderly( 1. 97( 1. 48-2. 54)) was statistically higher than female( 1. 82( 1. 42-2. 33))( χ~2= 22. 3383, P < 0. 0001). The prevalence of VAD among Chinese rural elderly residents was 2. 28%, 2. 79% for ordinary rural residents and 1. 53% for poor rural residents. The marginal VAD rate of Chinese rural elderly residents was 6. 30%, 6. 84% for ordinary rural residents and 5. 51% for poor rural residents. The prevalence of VAD and marginal VAD for male was 2. 18% and5. 57%, respectively. The prevalence of VAD and marginal VAD for female was 2. 38%and 7. 21%, respectively. No statistically difference was observed between different genders. The prevalence of VAD was 1. 93%, 3. 17% and 1. 47% for different age groups( 60 ~ 69, 70 ~ 79 and above 80 years old), and no statistically difference was observed between different age groups. The prevalence of marginal VAD was 5. 87%, 6. 20% and 11. 74% for different age groups, and statistically difference was observed between different age groups( χ~2= 7. 3858, P = 0. 039).

CONCLUSION

Chinese rural elderly population has a certain degree of vitamin A deficiency and marginal deficiency, the marginal deficiency of the elderly over 80 years old is more common.

Reference Values of 14 Serum Trace Elements for Pregnant Chinese Women: A Cross-Sectional Study in the China Nutrition and Health Survey 2010-2012

The development of reference values of trace elements is recognized as a fundamental prerequisite for the assessment of trace element nutritional status and health risks. In this study, a total of 1400 pregnant women aged 27.0 ± 4.5 years were randomly selected from the China Nutrition and Health Survey 2010–2012 (CNHS 2010–2012). The concentrations of 14 serum trace elements were determined by high-resolution inductively coupled plasma mass spectrometry. Reference values were calculated covering the central 95% reference intervals (P2.5–P97.5) after excluding outliers by Dixon’s test. The overall reference values of serum trace elements were 131.5 (55.8-265.0 μg/dL for iron (Fe), 195.5 (107.0–362.4) μg/dL for copper (Cu), 74.0 (51.8–111.3) μg/dL for zinc (Zn), 22.3 (14.0–62.0) μg/dL for rubidium (Rb), 72.2 (39.9–111.6) μg/L for selenium (Se), 45.9 (23.8-104.3) μg/L for strontium (Sr), 1.8 (1.2–3.6) μg/L for molybdenum (Mo), 2.4 (1.2–8.4) μg/L for manganese (Mn), 1.9 (0.6–9.0) ng/L for lead (Pb), 1.1 (0.3-5.6) ng/L for arsenic (As), 835.6 (219.8–4287.7) ng/L for chromium (Cr), 337.9 (57.0–1130.0) ng/L for cobalt (Co), 193.2 (23.6–2323.1) ng/L for vanadium (V), and 133.7 (72.1–595.1) ng/L for cadmium (Cd). Furthermore, some significant differences in serum trace element reference values were observed between different groupings of age intervals, residences, anthropometric status, and duration of pregnancy. We found that serum Fe, Zn, and Se concentrations significantly decreased, whereas serum Cu, Sr, and Co concentrations elevated progressively compared with reference values of 14 serum trace elements in pregnant Chinese women. The reference values of serum trace elements established could play a key role in the following nutritional status and health risk assessment.

MELD and Child-Pugh Scores Are Related to Immune Status of Intrahepatic Natural Killer Cells in Liver Transplant Candidates

BACKGROUND

The role and phenotypic alterations of intrahepatic natural killer (NK) cells in liver disease were investigated. Although intrahepatic NK cells reportedly functionally deteriorate in the fibrotic liver, it remains unclear how the clinical severity of liver disease affects intrahepatic NK cells in patients with advanced liver failure.

METHODS

We analyzed the phenotypic properties of intrahepatic NK cells by using mononuclear cells extracted from ex vivo liver perfusate effluents from patients who underwent liver transplantation. The relationship between the clinical severity of liver disease and the phenotype of intrahepatic NK cells in these patients was also evaluated. To estimate the immunological responsiveness of intrahepatic NK cells, phenotypic enhancement after interleukin-2 stimulation was analyzed.

RESULTS

Intrahepatic NK cells from patients with advanced liver failure exhibited down-regulated monomodal expression of NKp46, a major activating molecule. Notably, the expression level of NKp46 decreased depending on the severity of liver disease, Model for End-Stage Liver Disease score, and Child-Pugh score rather than the etiology. After in vitro recombinant interleukin-2 stimulation, the enhancement of expression of cytotoxic molecules, NKp44, and tumor necrosis factor-related apoptosis-inducing ligand was significantly impaired in intrahepatic NK cells from patients with liver failure, concurrently with decreased expression of CD122 and interleukin-2 receptor beta.

CONCLUSIONS

Our results suggest that terminal deterioration of liver environments by chronic liver disease impairs the potential of local NK cells, depending on the severity of the deterioration. These influences of advanced liver failure on intrahepatic NK cells may be attributed to multicentric carcinogenesis in patients with liver failure.

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.

The effect of recombinant human lactoferrin from the milk of transgenic cows on Salmonella enterica serovar typhimurium infection in mice

Lactoferrin (LF) is a multifunctional protein with antibacterial and immunomodulatory activities. Given this beneficial effect, transgenic approaches have been used to produce lactoferrin. The aim of the current study was to investigate the in vivo effect of recombinant human lactoferrin (rhLF) from the milk of transgenic cows on Salmonella enterica serovar typhimurium (ST) infection in mice. Two hours before the infection with 0.3 ml at 2 × 10(5) CFU ml(-1) of ST, each animal in the ST + rhLF group received 0.3 ml of rhLF with 20 mg ml(-1) concentration while the ST group received PBS as placebos with the same volume through oral gavage. The mice were infected with ST once only on the first day. After the infection, the mice received 0.3 ml of rhLF with 20 mg ml(-1) (6 mg d(-1)) concentration or PBS, respectively, for 7 days. Mortality and weight were monitored daily. Bacterial enumeration in the blood, liver, and spleen and histopathological analysis of the liver, spleen, kidney and intestine were conducted. The results showed that rhLF decreased the bacterial load in the liver and spleen of mice, reduced the degree of mice hepatomegaly and splenomegaly, and attenuated infectious inflammation with less histopathological abnormalities in the liver, spleen and kidney of mice in the ST infection. This study showed that rhLF with 6 mg per day had antibacterial activity of alleviating the infection caused by ST bacteria, which indicated that rhLF could be used as a supplement in special products.

Serum Copper Status in School-Age Children and Pregnant Women in China Nutrition and Health Survey 2010-2012

Serum copper is an insensitive but reliable biomarker reflecting the change of copper nutritional status in both depleted and replete populations. The current study aimed to establish the reference values of serum copper in school-age children and pregnant women in China and to explore the adequate range of serum copper for both these two categories of people. A multistage, stratified, random sampling combined with probability proportionate to regional size sampling method was employed. A total of 4019 subjects (2736 school-age children and 1283 pregnant women) were selected from China Nutrition and Health Survey 2010-2012 (CNHS 2010-2012). The concentration of serum copper was determined by sector field inductively coupled plasma mass spectrometry (SF-ICP-MS). The adequate range of serum copper was determined by the logistic sigmoid saturation curve of the median derivatives. The median concentration of serum copper was 1140.9 μg/L with a range of 746.7-1677.6 μg/L for school-age children and 1933.4 μg/L with a range of 947.4-3391.4 μg/L for pregnant women. The adequate range of serum copper was 905.7-1440.7 μg/L for school-age children and 1308.8-2537.8 μg/L for pregnant women. These parameters represent an essential prerequisite for the assessment of copper nutritional status, as well as nutrition interventions.

[Study on the anemia status of Chinese urban residents in 2010-2012]

OBJECTIVE

The level of blood hemoglobin and the anemia status of Chinese urban residents in 2010-2012 was analyzed.

METHODS

All the data in this study came from the China Nutrition and Health Survey in 2010-2012. By using multi-stage stratified sampling and population proportional stratified random sampling method, 74 276 residents aged above 6 from 34 metropolis and 41 middle-sized and small cities were included in this study. The concentration of blood hemoglobin was determined by cyanmethemoglobin method. Anemia was judged by the anemia standard recommended by WHO, combined with elevation correction standard. The level of blood hemoglobin, the prevalence of anemia and the 95%CI value were analyzed by using the complex sampling weighted processing, combined with the population figures released by the National Bureau of Statistics in 2009.

RESULTS

In 2010-2012, the level of blood hemoglobin of Chinese city population was(144.16 ± 0.78)g/L, (152.88 ± 0.94)g/L for male and(135.01 ± 0.71)g/L for female, while (145.65 ± 1.22)g/L for metropolis and (143.90 ± 0.89)g/L for small and medium-sized. The anemia prevalence of Chinese city population (pregnant women were not included) was 9.7%(95%CI: 9.4%-10.1%), 6.8%(95%CI: 6.4%-7.3%) for male and 12.8%(95%CI: 12.2%-13.4%) for female, while 8.5%(95% CI: 8.0%-9.0%) for metropolis and 10.0%(95%CI: 9.5%-10.4%) for small and medium-sized. The anemia prevalence of 18-44 women (15.4%, 95%CI: 14.3%-16.6%) was the highest among all the age-groups, and the average anemia prevalence of people more than 60 years-old (including) (12.5%, 95%CI: 11.8%-13.2%) was higher than the other age-groups.

CONCLUSION

The anemia prevalence of Chinese city population in 2010-2012 was obviously decreased in comparison of 10 years ago, while, more attention and improvement measures should be take upon women at reproductive age and the elder people.

[Application of three different methods for estimating of the plasma volume in children]

OBJECTIVE

To investigate the difference between three methods for estimating the plasma volume in children.

METHODS

The blood volume of 57 children from 10 to 12 years old were estimated by weight, formula proposed by Woodhead, and by bioelectrical impedance analysis( BIA), the effect and consistency of three methods were also compared.

RESULTS

There was no difference between three methods in blood volume estimating( P > 0. 05). According to the results of Passing & Bablok regression regression analysis, the residual standard deviation( RSD) was 85. 88, 122. 83 and 111. 24. The regression equation were: y_(Woodhead)= 577. 356224 + 0. 800525x_(BW); y_(BIA)=1091. 590338 + 0. 653032x( BW); y( BIA)= 560. 545257 + 0. 843899x_(Woodhead), and there was no obvious departure from the linear correlation( P > 0. 05). After regrouping by the percent body fat, there were differences between three methods in weight in overweight and obese children group( P < 0. 05), the blood volume estimated by weight was thehighest, and by the BIA was the lowest. While in normal group there was no difference between three groups(P<0. 05).

CONCLUSION

Three methods in blood volume estimating has a good consistency, estimating by body weight and formula have the virtue of convenience. Method of BIA is extremely fit for application in children with higher body fat.

[Systemic evaluation of zinc nutritional status for children aged 2-5 years from rural areas of China in 2002]

OBJECTIVE

To perform zinc nutritional assessment of children aged 2- 5years in rural areas of China according to the joint recommendation by the WHO /UNICEF / IAEA / IZi NCG.

METHODS

Based on the project of China Nutrition and Health Survey 2002( CNHS 2002), a stratified sampling combined with the probability proportional to population size sampling method was employed. The concentration of plasma zinc was determined by high resolution inductively coupled plasm mass spectrometry, and the data of dietary zinc intake and the physical examination was collected. The assessment of zinc nutrition was obtained by 3 aspects of indicators involving plasma zinc, dietary zinc intake and the development of growth.

RESULTS

Plasma zinc concentration was 714. 9 μg / L, and 45. 5% of children with zinc deficiency. Dietary zinc intake was 5. 9 mg / d, and the prevalence of inadequate dietary zinc intake was 18. 1%. The height for age Z score was- 0. 8, with 18. 2% of children who were stunted.

CONCLUSION

Zinc nutritional status of children aged 2- 5 years in rural areas is poor in the CNHS 2002. The status of plasma zinc is utmost serious in comparison withother indicators. The status of zinc nutrition in children aged 2- 5 years from the 4th rural areas is required to be continuous attention. Zinc nutrional assessment provides an extremely useful information and technical reference for early childhood.

Comparison on the status of vitamin A in 6- to 13- year-old children between 2002 and 2012 in China

BACKGROUND

Vitamin A deficiency is recognized as a major public-health nutrition issue in the developing countries. Limited hospital sources and sample sizes are available in most of the existing studies associated with healthy school-age children. The aim of this study was to compare vitamin A status of 6- to 13-year-old healthy children in China between 2002 and 2012.

METHODS

According to China National Nutrition and Health Survey 2002 (CHNNS2002) and CHNNS2010-2013, we choose 6- to 13-year-old children as the research object. We measure the serum retinol concentrations of the children using high performance liquid chromatography (HPLC). The children were divided into two groups: 6- to 9-year-old and 10- to 13-year-old. The areas were divided into urban and rural area.

RESULTS

Total number of the children (6- to 13-year old) was 8170 in 2002 survey, and it was 6016 in 2012 survey. In 2012, the vitamin A level of the children was higher than that in 2002 (t = 39.26, p = 0.000). The level of vitamin A in 10- to 13-year-old group was higher than that in 6- to 9-year-old group across areas and genders between 2002 and 2012. There was no difference on the incidence of vitamin A deficiency in all the children between 2002 and 2012, but in 2012 the incidence of vitamin A deficiency in the urban children was higher than that in 2002 (x (2) = 45.456,p = 0.000). The incidence of vitamin A deficiency in 10- to 13-year-old group was lower than that in 10- to 13-year-old group across areas and genders between 2002 and 2012. In 2012, the incidence of marginal vitamin A deficiency in the children was lower than that in 2002 (x (2) = 861.604, p = 0.000). Similar phenomena were also found in across area groups. The incidence of marginal vitamin A deficiency in 10- to 13-year-old group was lower than that in 6- to 9-year-old group across areas and genders between 2002 and 2012. There was no difference in vitamin A status of the children across the area, gender and age groups between 2002 and 2012.

CONCLUSION

Vitamin A nutritional status of the children in 2012 has been significantly improved compared with that in 2002. However, vitamin A deficiency was still a moderate public health problem in Chinese children, especially in younger school-age children. Consequently, controlling the incidence of vitamin a deficiency is imperative for promoting Chinese children's health.

[Association of leptin receptor gene polymorphrism with metabolic syndrome in older Han adults from major cities in China]

OBJECTIVE

To investigate the relationship of leptin receptor gene rs1137100 and rs1137101 single nucleotide polymorphrism (SNP) with metabolic syndrome (MS) in older Han adults from major cities in China.

METHODS

A total of 2082 older Han adults were selected from 18 major cities including 15 provinces/municipalities of China National Nutrition and Health Survey in 2002. According to the MS definition proposed by Joint Interim Statement (JIS), the subjects were divided into MS and control groups. Plasma leptin and insulin levels were measured. The genotypes of rs1137100 and rs1137101 were detected by Taqman method. Association of genotypes of leptin receptor gene SNPs with MS was investigated.

RESULTS

The MS group showed higher body mass index (BMI), waist circumference, fasting serum glucose, systolic blood pressure (SBP) and diastolic blood pressure (DBP), triglycerides (TG), serum total cholesterol (TC), insulin, homeostasis model of assessment for insulin resistence index (HOMA-IR) and leptin levels than those of control individuals, while the high density lipoprotein cholesterol (HDL-c) was significantly lower than the control group. The, GG, AA, GA genotypes distribution and the A allele frequency of rs1137100 and rs1137101 were similar between the two groups. The DBP and SBP level were obviously higher in AA genotype. The HDL-c concentration Was significantly lower in AA and GA + AA genotype. The AA and GA genotypes carriers in rs1137100 had similar risk for MS when comparing with the GG genotypes, and the OR values were 1.23 (95% CI 0.90-1.67) and 2.23 (95% CI 0.83-6.44), respectively. The AA and GA genotypes carriers in rs1137101 had similar risk for MS when comparing with the GG genotypes, and the OR values were 1.23 (95% CI 0.90-1.67) and 2.23 (95% CI 0.83-6.44), respectively.

CONCLUSION

Leptin receptor genes rs1137100 and rs1137101 are not associated with pathogenesis of MS in older Han adults, but it may relate with hypertension or lipid abnormality.

Non-Heme Iron Absorption and Utilization from Typical Whole Chinese Diets in Young Chinese Urban Men Measured by a Double-Labeled Stable Isotope Technique

BACKGROUND

This study was to observe the non-heme iron absorption and biological utilization from typical whole Chinese diets in young Chinese healthy urban men, and to observe if the iron absorption and utilization could be affected by the staple food patterns of Southern and Northern China.

MATERIALS AND METHODS

Twenty-two young urban men aged 18-24 years were recruited and randomly assigned to two groups in which the staple food was rice and steamed buns, respectively. Each subject received 3 meals containing approximately 3.25 mg stable 57FeSO4 (the ratio of 57Fe content in breakfast, lunch and dinner was 1:2:2) daily for 2 consecutive days. In addition, approximately 2.4 mg 58FeSO4 was administered intravenously to each subject at 30-60 min after dinner each day. Blood samples were collected from each subject to measure the enrichment of the 57Fe and 58Fe. Fourteen days after the experimental diet, non-heme iron absorption was assessed by measuring 57Fe incorporation into red blood cells, and absorbed iron utilization was determined according to the red blood cell incorporation of intravenously infused 58Fe SO4.

RESULTS

Non-heme iron intake values overall, and in the rice and steamed buns groups were 12.8 ±2.1, 11.3±1.3 and 14.3±1.5 mg, respectively; the mean 57Fe absorption rates were 11±7%, 13±7%, and 8±4%, respectively; and the mean infused 58Fe utilization rates were 85±8%, 84±6%, and 85±10%, respectively. There was no significantly difference in the iron intakes, and 57Fe absorption and infused 58Fe utilization rates between rice and steamed buns groups (all P>0.05).

CONCLUSION

We present the non-heme iron absorption and utilization rates from typical whole Chinese diets among young Chinese healthy urban men, which was not affected by the representative staple food patterns of Southern and Northern China. This study will provide a basis for the setting of Chinese iron DRIs.

Distribution of iron status among urban Chinese women

BACKGROUND AND OBJECTIVES

To assess the distribution of serum ferritin, serum soluble transferrin receptor and body iron among girls and women by age and anaemia.

METHODS AND STUDY DESIGN

Serum ferritin, serum soluble transferrin receptor and high sensitive C-reactive protein of 1625 and 1372 women in general and anaemic were measured in the National Health and Nutrition Survey commenced in 2010.

RESULTS

The distributions of serum ferritin, serum soluble transferrin receptor and body iron for 6-11-y, 12-17-y, 18-44-y, 45-59-y and >=60-y subgroups were significantly different. Both in population-representative women and those anaemic, the iron status of 18-44-y women was the lowest and that of 12-17-y girls the second lowest. The iron status of anaemic women was lower than that in representative women at ages 12-17 y, 18-44 y, 45-59 y and >=60 y.

CONCLUSION

Iron status in women of different ages and anaemic had different distributions, but consistently lower than that of population-representative women. The observed iron status of Chinese urban women supports program planning for iron nutrition promotion in women. Iron status information is also needed for men and to understand the pathogenesis which may be related to intake or loss.

Effect of NaFeEDTA-fortified soy sauce on zinc absorption in children

NaFeEDTA has been applied in many foods as an iron fortificant and is used to prevent iron deficiency in Fe-depleted populations. In China, soy sauce is fortified with NaFeEDTA to control iron deficiency. However, it is unclear whether Fe-fortified soy sauce affects zinc absorption. To investigate whether NaFeEDTA-fortified soy sauce affects zinc absorption in children, sixty children were enrolled in this study and randomly assigned to three groups (10 male children and 10 female children in each group). All children received daily 3 mg of (67)Zn and 1.2 mg of dysprosium orally, while the children in the three groups were supplemented with NaFeEDTA-fortified soy sauce (6 mg Fe, NaFeEDTA group), FeSO₄-fortified soy sauce (6 mg Fe, FeSO₄ group), and no iron-fortified soy sauce (control group), respectively. Fecal samples were collected during the experimental period and analyzed for the Zn content, (67)Zn isotope ratio and dysprosium content. The Fe intake from NaFeEDTA-fortified and FeSO₄-fortified groups was significantly higher than that in the control group (P < 0.0001). The daily total Zn intake was not significantly different among the three groups. There were no significant differences in fractional Zn absorption (FZA) (P = 0.3895), dysprosium recovery (P = 0.7498) and Zn absorption (P = 0.5940) among the three groups. Therefore, NaFeEDTA-fortified soy sauce does not affect Zn bioavailability in children.

Prevalence and influence factors of vitamin A deficiency of Chinese pregnant women

Background

Vitamin A plays an important role in the periods of rapid cellular growth and differentiation, especially during pregnancy, which is supplied by the mother to the fetus. The aim of this study is to assess the prevalence and potential influence factors of prenatal VAD of Chinese pregnant women.

Methods

China National Nutrition and Health Survey 2010–2013(CHNNS2010–2013) is a nationally representative cross-sectional study. It involved the random selection of 150 districts (urban) or counties (rural). Each site randomly selected 30 pregnant women. Because volume of blood and incomplete data was taken into consideration,the final sample was formed by 1209 participants. Serum retinol concentrations were measured by high performance liquid chromatography. Characteristics of the pregnant women were collected by a questionnaire. Comparing retinol level across categories of independent variables was tested by the Mann-Whitney U test. Logistic and linear regression analyses were used to identify influence factors of Chinese pregnant women.

Results

The mean serum retinol level of the pregnant women was 1.63 μmol/L (95 % CI 1.60–1.67) and 64[5.3 % (95 % CI 4.03–6.56)] had VAD. The odds of VAD were significantly higher among the pregnant women in the poor rural areas and without college or university education and low- income. Pregnant women in the second and third trimester had 2.40 (95 % CI 1.05–5.46) and 2.82 (95 % CI 1.34–5.93) times increased odds of VAD compared with those in the first trimester respectively. Pregnant women of drinker had 3.10(1.65–5.81) times increased odds of VAD compared with those no drinker. Pregnant smokers had 5.68 (95 % CI 2.23–14.49) times higher odds of VAD compared with pregnant with non-smoker without passive smoking.

Conclusions

VAD is of mild public-health issue in Chinese pregnant women. Such as : in the poor rural areas and without received college or university education and low- income and advanced gestational age and unhealthy lifestyles of pregnant women such as smoking and drinking. These were pertinent influence factors of VAD.

HPV16 E6 mutations and p53 codon72 polymorphism among women with cervical intraepithelial neoplasia 2 and 3 in China

OBJECTIVE

To study the distribution of HPV16 E6 gene mutations and p53 codon72 polymorphism among women with HPV16+ cervical precancerous lesions and explore their relationship with the risk of cervical intraepithelial neoplasia (CIN) 2, 3. Materials and Meth- ods: This study analyzed a total of 112 cases of exfoliated HPV16+ cervical cell specimens which were divided into group I (normal and CIN1, 55 cases) and group2 (CIN2, 3, 57 cases). Among the 112 specimens, 85 cases were successfully amplified for HPV E6 gene by PCR and the PCR products were sequenced directly. P53 codon72 region was also amplified from the 112 specimens and the PCR products were sequenced directly and compared with the standard sequence.

RESULTS

Among the 85 amplified HPV sequences, point mutations such as T178G, T350G, G132A, A442C, T310G, G94T, C551A, etc. were found, among which, T178G showed the highest rate (51.76%). The rate of HPV16 E6 mutation T178G in CIN2, 3 group was significantly higher than that in normal and CINI group, i.e., in the 112 amplified p53 codon72 sequences, the distribution of Pro/Pro genotype in normal, and CIN1 group was significantly different from that in CIN2, 3 groups, and the disease risk of Pro/Pro genotype was much higher than that of Arg/Arg and Arg/Pro genotypes.

CONCLUSION

HPV16 E6 T178G mutation increases the disease risk of CIN2, 3. Meanwhile, compared with Arg/Arg and Arg/Pro genotypes, p53 codon72 Pro/Pro genotype more associated with the disease risk of CIN2, 3.

Association of Vitamin A Status with Overnutrition in Children and Adolescents

This study was conducted to examine the possible association between vitamin A status and overnutrition in Chinese urban children and adolescents. Weight, height and serum retinol were assessed in total 3457 children (7–9.9 years of age) and adolescents (10–17 years of age), using urban region data from the China National Nutrition and Health Survey 2010–2013 (CHNNS2010-2013) which is a nationally representative cross-sectional study. Prevalence of low serum concentration of retinol was 26.8% and 12.24% for overweight. Retinol inadequacy was significantly higher in children (32.13%) than in adolescents (24.48%). The average of retinol was significantly higher in overnutrified 42.32 μg/dL versus non-overnutrified 41.05 μg/dL (p = 0.00) children and adolescents. Overnutrified children and adolescents presented a greater chance of an increase in serum concentration of retinol (odds ratio 1.34, 95% confidence interval 1.10–1.63, and 1.48, 95% confidence interval (1.26–1.74) when compared with non-overnutrified children. An important correspondence between vitamin A deficiency and overnutrition was found. Non-overnutrified children and adolescents may have a greater chance of presenting low concentrations of retinol. Future public health strategies focused on the overnutrified population and vitamin A supplements should consider the effect of retinol on urban children and adolescents in China.

[Study on iron store status for women in the poor rural areas in China from 2010 to 2012]

OBJECTIVE

To quantitatively assess the concentration and the distribution of the body iron (BI) for women in the poor rural areas.

METHODS

Resampling based on the blood sample of Nutrition and Health Survey in China from 2010 to 2012, serum ferritin (SF) and serum soluble transferrin receptor (sTfR) were measured for the selected blood samples by immunoturbidimetric assay. BI was calculated, and the concentrations and distribution in different aged subgroup were assessed. Distribution of BI subgrouped in different aged women was compared. The correlations of BI to hemoglobin (Hb), SF and sTfR were analyzed.

RESULTS

The average levels of BI were (7.35 ± 2.37) mg/kg for schoolgirls aged 6-11 years, (6.50 ± 3.59) mg/kg for adolescent girls aged 12-17 years, (6.07 ± 4.78) mg/kg for women of childbearing aged 18-44 years, (8.60 ± 4.45) mg/kg for women aged 45-59 years, and (10.35 ± 3.38) mg/kg for elderly female aged ≥ 60 years, respectively. The proportion of low BI in the 12-17 years and 18-44 years women was the highest. BI level was positively correlated to SF and negatively correlated to sTfR (P < 0.01). BI level was positively correlated to Hb in the BI < 0 mg/kg subgroup.

CONCLUSION

The BI methodology allows the full range of iron status of populations to be evaluated. The iron status for adolesecent girls aged 12-17 years and women of childbearing aged 18-44 years should be improved.

[Comparison for ELISA and CLIA of serum 25-hydroxy vitamin D determination]

OBJECTIVE

To estimate the bias between the enzyme linked immunosorbent assay (ELISA) and chemiluminescence immunoassay (CLIA) of serum 25-hydroxy vitamin D (25 (OH) D) determination, and to evaluate the correspondence of two methods.

METHODS

Forty human serum samples were collected, and the serum 25 (OH) D were determined by immunodiagnostic systems 25-hydroxy vitamin D EIA and immunodiagnostic systems iSYS analyser. According to the standards of NCCLS EP9-A2 files, the within and without outlier, test adequate range, used linear regression procedure, and compare average and maximum bias between these two methods were excluded.

RESULTS

In the linear regression analysis, the results of the two methods were correlated, y = 0.995x + 2.3928, r = 0.981. The relative standard deviation between these two methods was smaller with the higher serum 25(OH) D levels.

CONCLUSION

The correlation and repeatability of serum 25 (OH) D determination by ELISA and CLIA are fine.

[Effect of different dietary fat intake on blood lipids, body fat, adiponectin and leptin on energy balance status in rats]

OBJECTIVE

To investigate the effects of different dietary fat intake on body fat, adiponectin and leptin on energy balance status in rats.

METHODS

Forty male SD rats were randomly assigned to four groups. Rats in low fat, normal fat, medium fat and high fat group were fed equal energy diets of low fat diet (5% energy from fat), normal diet (15% energy from fat), medium fat diet (25% energy from fat) and high fat diet (40% energy from fat) respectively. Blood glucose and lipids were analyzed at 0, 5 and 10 weeks. The level of serum adiponectin and leptin was tested at 0 and 10 weeks. At the end of 10 weeks, the rats were sacrificed, the perirenal and periepididymis fat were separated and weighed. The mRNA of adiponectin and leptin in fat tissues were determined by realtime PCR.

RESULTS

After the 5 and 10 weeks, the levels of serum triglyceride of rats in medium fat group and high fat group were lower than those in low fat group and normal fat group. At the end of 10 weeks, the expression of adiponectin mRNA in fat tissues in medium fat group was lower than those in low fat group. There were no significant differences among four groups in body fat, blood glucose, blood cholesterol, serum adiponectin and leptin, and the expression of leptin mRNA in fat tissues.

CONCLUSION

In energy balance status, different dietary fat intake had no effects on body fat, blood glucose, blood cholesterol, serum adiponectin and leptin in rats.

[Study on IgE mediated food allergy of 3 -12 years urban children in China]

OBJECTIVE

To study the situation of IgE-mediated food allergy of Chinese urban children, including the rate of food allergy and the main food allergens in children.

METHODS

All the serum samples were selected from the serum bank built by the national nutrition and health survey of Chinese residents. Total IgE of all the samples were tested by enzyme linked immunosorbent assay, and the sIgE of TIgE-positive samples were then tested by immunoblotting.

RESULTS

A total of 5190 samples were selected from serum bank, and the rate of IgE-mediated food allergy was 3.20%. The rate of IgE-mediated food allergy was 2.70% in big cities, while it was 3.77% in small and medium-sized cities. The rate was gradually decreased with age grown.

CONCLUSION

The situation of food allergy in children and the main allergens could be preliminary determined by testing the serum total IgE level and specific IgE.

[Study on efficiency of iron utilization in prepubertal female children]

OBJECTIVE

To investigate the iron utilization of prepubertal female children.

METHODS

27 female children from 10 to 12 years old were selected and given 57Fe as a tracer, in conventional diet mode, the blood samples in 1 day before test, 14 days and 28 days after tracer given were taken, and were conducted into red blood cell sample. The iron content and changes of isotope abundance in samples were analyzed and combined with blood volume to get the utilization of iron in RBC.

RESULTS

The erythrocyte incorporation rate( of dose) in 14 days and 28 days were (19.84 +/- 0.53)% and (18.75 +/- 0.40)% (P > 0.05). The erythrocyte incorporation rate( of absorption) were (93.49 +/- 2.27)% and (88.73 +/- 0.43)% respectively, and there was a significantly difference (P < 0.05).

CONCLUSION

It is feasible and accurate to evaluate the iron utilization using erythrocyte incorporation rate, which is tested by single stable isotopes tracer technique. Prepubertal female children has a higher utilization of iron, and the 14 days after tracer given is a effective entry point in erythrocyte incorporation study.

[Evaluation on the iron absorption of prepubertal children using stable isotopic tracer]

OBJECTIVE

To investigate the iron absorption of prepubertal children using stable isotopic tracer.

METHODS

57 subjects were orally given 57FeSO4, in conventional diet mode, before breakfast and supper and totally for 5 days. All the fecal during the specified time were collected, pre-conducted and determined by AAS and MC-ICP-MS to evaluation the iron absorption of prepubertal children.

RESULTS

The iron absorption rate of male and female were (26.71 +/- 2.94)% and (29.76 +/- 2.20)%, and the correction absorption rate of iron were (27.45 +/- 2.83)% and (31.01 +/- 2.48)%, absorption of female were higher than that of male (P < 0.05).

CONCLUSION

In the condition of fasting oral SI, there is a high iron absorption rate of prepubertal children, and absorption rate of female is higher.

[Simultaneous determination of 12 trace elements in children plasma sample by high resolution inductively coupled plasma mass spectrometry]

OBJECTIVE

To establish a method of determination of 12 trace elements (B, V, Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Sr, Mo) in children plasma for the fast,direct dilution by HR-ICP-MS.

METHODS

The plasma samples were reconstituted, centrifuged for 15 minutes, then were added the internal elements of Ga and Y, diluted with 0.5% HNO3 by 1 : 20 (V/V). HR-ICP-MS was optimized and applied for the analysis.

RESULTS

Detection limits were 0.001 - 0.035 microg/L, method detection limits of trace elements were 0.012 - 0.702 microg/L, coefficient of determination (R2) ranged from 0.9983 to 1. 0000 and the 3 levels of spiked recovery were between 85.86% and 121.34%, intra-day and inter-day precision were 0.52% - 5.62% and 1.21% - 10.21%, as well as bovine serum certified samples further verified the accuracy. 12 trace elements in plasma of the children aged 3 -12 years from poor rural in 2002 CNNHS, had been determined by Optimized HR-ICP-MS.

CONCLUSION

Preparation of plasma samples with 0.5% HNO3 combined with HR-ICP-MS were applied for a large scale of sample analysis.