Pb is a well-known toxic metal that has attracted considerable attention because of its ubiquitous distribution in the environment owing to the recent industrialization and rapid urbanization in China. In general, Pb ...Pb is a well-known toxic metal that has attracted considerable attention because of its ubiquitous distribution in the environment owing to the recent industrialization and rapid urbanization in China. In general, Pb from contaminated food, water, and dust enters the body through different channels,spreads throughout the body, combines with multiple amino acids, and interferes with normal physical activity.展开更多
Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±1 y...Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±1 years with body mass index 22.0±1.4 kg/m 2 were recruited. TEE was measured by the DLW method, and basal energy expenditure (BEE) was determined by indirect calorimetry. We also conducted 24-h activity, energy balance and factorial approach to estimate energy requirements of the subjects. Results TEE of subjects by DLW method was 9.45±0.57 MJ/day (2258±180 kcal/day). The 24-h activity was 10.80±0.33 MJ/day (2582±136 kcal/day). The energy requirement, derived from energy balance observations, was 9.93±1.32 MJ/day (2373±315 kcal/day). The BEE of 6.65±0.28 MJ/day (1589±67 kcal/day), calculated by the adjusted Schofield equation, was significantly higher (P<0.001) than that measured by indirect calorimetry, 5.99±0.66 MJ/day (1433±158 kcal/day). The TEE derived from the factorial approach was 10.31±0.43 MJ/day (2463±104 kcal/day). Conclusion The TEE of Chinese young men measured by the DLW method was about 10% lower than the current recommended nutrient intake (RNI), suggesting that the RNI for Chinese men maybe overestimated. Further studies are warranted to determine the value of the estimated energy requirement.展开更多
Objectives To evaluate the distribution by age and sex of serum high-sensitivity C-reactive protein(hsCRP)in an urban Chinese population and to provide a profile prediction for the risk of bacterial infection,inflamma...Objectives To evaluate the distribution by age and sex of serum high-sensitivity C-reactive protein(hsCRP)in an urban Chinese population and to provide a profile prediction for the risk of bacterial infection,inflammatory diseases,or tissue damages in the body.Methods Serum hsCRP was determined using the Roche Tina-quant immuno-turbidimetric assay on a Hitachi 7600–010 automatic biochemical analyzer(Roche Diagnostics)in 1,572 males and 1,800 females,including 78 pregnant women,who were derived from the National Health and Nutrition Survey in2010–2012.Results The average hsCRP concentration in urban China was 0.68 mg/L for males and 0.65 mg/L for females.Significant differences in hsCRP were found among different age groups(P<0.05).Monitoring results showed no significant differences among the 6–11,45–59,and≥60-year-old groups in the comparison of hsCRP between males and females in large cities.However,hsCRP concentration was significantly higher in men aged 12–17 and 18–44 years than in women.Conclusion The distribution of the hsCRP status of residents in large cities in China was influenced by age and gender,and the hsCRP levels of both sexes increased gradually with age.In addition,hsCRP concentration was higher in healthy pregnant women than in non-pregnant women.Basing on our results,we recommend that this parameter be included in future national and international screening for early detection of various illnesses.展开更多
Objective To accurately calculate the protein requirements in Chinese young adults using the indicator amino acid oxidation technique. Methods Nine women and ten men received a restricted daily level of protein intake...Objective To accurately calculate the protein requirements in Chinese young adults using the indicator amino acid oxidation technique. Methods Nine women and ten men received a restricted daily level of protein intake (0.75, 0.82, 0.89, 0.97, and 1.05 g/kg), along with L-[1-13C]-leucine. Subjects' protein requirement was determined by a biphasic linear regression crossover analysis of F13CO2 data. In doing so, a breakpoint at the minimal rate of appearance of 13CO2 expiration specific to each level of dietary protein was identified. This trial was registered with the Chinese clinical trial registry as ChiCTR-ONC-11001407. Results The Estimated Average Requirement (EAR) and the Recommended Nutrient Intake (RNI) of protein for healthy Chinese young adults were determined to be 0.87 and 0.98 g/(kg·d), respectively, based on the indicator amino acid oxidation technique. Conclusion The EAR and RNI of mixed protein are 5% and 16% that are lower than the current proposed EAR and RNI (0.92 and 1.16 g/(kg·d), respectively), as determined by the nitrogen balance method. The respective EAR and RNI recommendations of 0.87 and 0.98 g/(kg·d) of mixed protein are estimated to be reasonable and suitable for Chinese youngadults.展开更多
Objective To determine the dietary zinc absorption in a Chinese elderly population and provide the basic data for the setting of zinc(Zn) recommended nutrient intakes(RNI) for Chinese elderly people. Methods A total o...Objective To determine the dietary zinc absorption in a Chinese elderly population and provide the basic data for the setting of zinc(Zn) recommended nutrient intakes(RNI) for Chinese elderly people. Methods A total of 24 elderly people were recruited for this study and were administered oral doses of 3 mg ^(67)Zn and 1.2 mg dysprosium on the fourth day. The primary macronutrients, energy, and phytic acid in the representative diet were examined based on the Chinese National Standard Methods. Fecal samples were collected during the experimental period and analyzed for zinc content, ^(67)Zn isotope ratio, and dysprosium content. Results The mean(± SD) zinc intake from the representative Chinese diet was 10.6 ± 1.5 mg/d. The phytic acid-to-zinc molar ratio in the diet was 6.4. The absorption rate of ^(67)Zn was 27.9% ± 9.2%. The RNI of zinc, which were calculated by the absorption rate in elderly men and women, were 10.4 and 9.2 mg/d, respectively. Conclusion This study got the dietary Zn absorption in a Chinese elderly population. We found that Zn absorption was higher in elderly men than in elderly women. The current RNI in elderly female is lower than our finding, which indicates that more attention is needed regarding elderly females' zinc status and health.展开更多
Objective This study aimed to measure the basal energy expenditure(BEE)of Chinese healthy adults and establish an accurate predictive equation for this population.Methods In total,470 Chinese healthy adults had their ...Objective This study aimed to measure the basal energy expenditure(BEE)of Chinese healthy adults and establish an accurate predictive equation for this population.Methods In total,470 Chinese healthy adults had their BEE measured using the Cosmed K4b2 portable metabolic system.Multiple linear regression analysis was applied to develop new optimal equations for predicting BEE.The bias,accuracy rate,concordance correlation coefficient(CCC),and root mean square error(RMSE)were used to evaluate the accuracy of the predictive equations.Results There was a significant difference in BEE between males and females,with 5,954 kJ/d and 5,089 kJ/d,respectively.People living in rural areas expended significantly higher BEE(5,885 kJ/d)than those in urban areas(5,279 kJ/d).Previous equations developed by Henry,Schofield,Harris-Benedict(HB),and Liu overestimated the BEE of Chinese healthy adults.The new equations derived from the present study displayed the smallest average bias and RMSE from the measured basal energy expenditure(mBEE).The CCC of the new equations was higher than other predictive equations,but it was lower than 0.8.There was no significant difference in the accuracy rate among all predictive equations.Conclusions Sex and regional differences in BEE were observed in Chinese healthy adults.Neither the widely used previous predictive equations nor the one derived in the present study were accurate enough for estimating the BEE of Chinese healthy adults.Further study is required to develop more accurate equations for predicting the BEE of Chinese healthy adults aged between 20–45 years.展开更多
Objective The goal of this study was to analyze protein requirements in healthy adults through a meta-analysis of nitrogen balance studies. Methods A comprehensive search for nitrogen balance studies of healthy adults...Objective The goal of this study was to analyze protein requirements in healthy adults through a meta-analysis of nitrogen balance studies. Methods A comprehensive search for nitrogen balance studies of healthy adults published up to October 2012 was performed, each study were reviewed, and data were abstracted. The studies were first evaluated for heterogeneity. The average protein requirements were analyzed by using the individual data of each included studies. Study site climate, age, sex, and dietary protein source were compared. Results Data for 348 subjects were gathered from 28 nitrogen balance studies. The natural logarithm of requirement for 348 individuals had a normal distribution with a mean of 4.66. The estimated average requirement was the exponentiation of the mean of the log requirement, 105.64 mg N/kg·d. No significant differences between adult age, source of dietary protein were observed. But there was significant difference between sex and the climate of the study site(P<0.05). Conclusion The estimated average requirement and recommended nutrient intake of the healthy adult population was 105.64 mg N/kg·d(0.66 g high quality protein/kg·d) and 132.05 mg N/kg·d(0.83 g high quality protein/kg·d), respectively.展开更多
Iodine is an element that is essential for the synthesis of thyroid hormones.Adequate intake of dietary iodine has been recognized as a critical factor for maintaining health[1].It is a well-known fact that iodine def...Iodine is an element that is essential for the synthesis of thyroid hormones.Adequate intake of dietary iodine has been recognized as a critical factor for maintaining health[1].It is a well-known fact that iodine deficiency can impede the production of thyroid hormones in both the mother and fetus,which increases the risk of brain damage in the fetal stage.Excess iodine can also result in a series of thyroid dysfunction symptoms such as goiter展开更多
Objective This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope tracertechnique.Methods Thirty boys(10.6±0.2 years)and 27 girls(10.4±0.2 year...Objective This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope tracertechnique.Methods Thirty boys(10.6±0.2 years)and 27 girls(10.4±0.2 years)were received oral 6 mg ^(57)Fe each day for 5 consecutive days.Venous blood samples were subsequently drawn to examine the change of total iron concentration and ^(57)Fe abundance at day 0,14,28,60,90,180,360,450,540,630,720.The iron physiological requirement was calculated by iron loss combined with iron circulation rate once ^(57)Fe abundance stabilized in human body.Results The iron physiological requirement was significantly lower in boys than those values in girls(16.88±7.12 vs.18.40±8.81μg/kg per day,P<0.05).Correspondingly,the values were calculated as 722.46±8.43μg/day for boys and 708.40±7.55μg/day for girls,respectively.Considering nearly 10%iron absorption rate,the estimated average iron physiological requirement was 6.0 mg/day in boys and 6.2 mg/day in girls.Conclusion This study indicate that iron physiological requirement could require more daily iron intake in girls as compare with the values in boys having the same body weight.These findings would be facilitate to the new revised dietary reference intakes.展开更多
Iodine is an essential component of thyroid hormones’biosynthesis and is crucial for normal growth and healthy development[1].If the amount of dietary iodine intake cannot match the long-term requirement,regardless o...Iodine is an essential component of thyroid hormones’biosynthesis and is crucial for normal growth and healthy development[1].If the amount of dietary iodine intake cannot match the long-term requirement,regardless of whether it is excessively low or high,it can cause various thyroid dysfunctions,including hyperthyroidism,hypothyroidism,and autoimmune thyroid diseases[2].展开更多
基金sponsored by the Danone Nutrition Fund [Grant no. DIC 2017-06]the Young Scholar Scientific Research Foundation of the Chinese Center for Disease Control and Prevention [Grant No. 2018A204]。
文摘Pb is a well-known toxic metal that has attracted considerable attention because of its ubiquitous distribution in the environment owing to the recent industrialization and rapid urbanization in China. In general, Pb from contaminated food, water, and dust enters the body through different channels,spreads throughout the body, combines with multiple amino acids, and interferes with normal physical activity.
基金supported by the projects of National Natural Science Foundation of China (No.30771811)the National Technology Research and Development Program in the Eleventh Five-Year Plan of China(No.2008BAI58B01)
文摘Objective Doubly labeled water (DLW) method is the gold standard for measuring total energy expenditure (TEE). We used this method to measure TEE in Chinese young men. Methods Sixteen healthy young men age 23±1 years with body mass index 22.0±1.4 kg/m 2 were recruited. TEE was measured by the DLW method, and basal energy expenditure (BEE) was determined by indirect calorimetry. We also conducted 24-h activity, energy balance and factorial approach to estimate energy requirements of the subjects. Results TEE of subjects by DLW method was 9.45±0.57 MJ/day (2258±180 kcal/day). The 24-h activity was 10.80±0.33 MJ/day (2582±136 kcal/day). The energy requirement, derived from energy balance observations, was 9.93±1.32 MJ/day (2373±315 kcal/day). The BEE of 6.65±0.28 MJ/day (1589±67 kcal/day), calculated by the adjusted Schofield equation, was significantly higher (P<0.001) than that measured by indirect calorimetry, 5.99±0.66 MJ/day (1433±158 kcal/day). The TEE derived from the factorial approach was 10.31±0.43 MJ/day (2463±104 kcal/day). Conclusion The TEE of Chinese young men measured by the DLW method was about 10% lower than the current recommended nutrient intake (RNI), suggesting that the RNI for Chinese men maybe overestimated. Further studies are warranted to determine the value of the estimated energy requirement.
基金supported by the National Key Research and Develepment Program of China 2016YFD0400602。
文摘Objectives To evaluate the distribution by age and sex of serum high-sensitivity C-reactive protein(hsCRP)in an urban Chinese population and to provide a profile prediction for the risk of bacterial infection,inflammatory diseases,or tissue damages in the body.Methods Serum hsCRP was determined using the Roche Tina-quant immuno-turbidimetric assay on a Hitachi 7600–010 automatic biochemical analyzer(Roche Diagnostics)in 1,572 males and 1,800 females,including 78 pregnant women,who were derived from the National Health and Nutrition Survey in2010–2012.Results The average hsCRP concentration in urban China was 0.68 mg/L for males and 0.65 mg/L for females.Significant differences in hsCRP were found among different age groups(P<0.05).Monitoring results showed no significant differences among the 6–11,45–59,and≥60-year-old groups in the comparison of hsCRP between males and females in large cities.However,hsCRP concentration was significantly higher in men aged 12–17 and 18–44 years than in women.Conclusion The distribution of the hsCRP status of residents in large cities in China was influenced by age and gender,and the hsCRP levels of both sexes increased gradually with age.In addition,hsCRP concentration was higher in healthy pregnant women than in non-pregnant women.Basing on our results,we recommend that this parameter be included in future national and international screening for early detection of various illnesses.
基金supported by the National Natural Science Foundation of China (No.81001247): Dietary reference intakes of protein for Chinese youths
文摘Objective To accurately calculate the protein requirements in Chinese young adults using the indicator amino acid oxidation technique. Methods Nine women and ten men received a restricted daily level of protein intake (0.75, 0.82, 0.89, 0.97, and 1.05 g/kg), along with L-[1-13C]-leucine. Subjects' protein requirement was determined by a biphasic linear regression crossover analysis of F13CO2 data. In doing so, a breakpoint at the minimal rate of appearance of 13CO2 expiration specific to each level of dietary protein was identified. This trial was registered with the Chinese clinical trial registry as ChiCTR-ONC-11001407. Results The Estimated Average Requirement (EAR) and the Recommended Nutrient Intake (RNI) of protein for healthy Chinese young adults were determined to be 0.87 and 0.98 g/(kg·d), respectively, based on the indicator amino acid oxidation technique. Conclusion The EAR and RNI of mixed protein are 5% and 16% that are lower than the current proposed EAR and RNI (0.92 and 1.16 g/(kg·d), respectively), as determined by the nitrogen balance method. The respective EAR and RNI recommendations of 0.87 and 0.98 g/(kg·d) of mixed protein are estimated to be reasonable and suitable for Chinese youngadults.
基金supported by the National Natural Science Foundation of China(No.81273073)
文摘Objective To determine the dietary zinc absorption in a Chinese elderly population and provide the basic data for the setting of zinc(Zn) recommended nutrient intakes(RNI) for Chinese elderly people. Methods A total of 24 elderly people were recruited for this study and were administered oral doses of 3 mg ^(67)Zn and 1.2 mg dysprosium on the fourth day. The primary macronutrients, energy, and phytic acid in the representative diet were examined based on the Chinese National Standard Methods. Fecal samples were collected during the experimental period and analyzed for zinc content, ^(67)Zn isotope ratio, and dysprosium content. Results The mean(± SD) zinc intake from the representative Chinese diet was 10.6 ± 1.5 mg/d. The phytic acid-to-zinc molar ratio in the diet was 6.4. The absorption rate of ^(67)Zn was 27.9% ± 9.2%. The RNI of zinc, which were calculated by the absorption rate in elderly men and women, were 10.4 and 9.2 mg/d, respectively. Conclusion This study got the dietary Zn absorption in a Chinese elderly population. We found that Zn absorption was higher in elderly men than in elderly women. The current RNI in elderly female is lower than our finding, which indicates that more attention is needed regarding elderly females' zinc status and health.
基金Supported by Key Projects of the National Science and Technology Pillar Program[No.2008BAI58B01].
文摘Objective This study aimed to measure the basal energy expenditure(BEE)of Chinese healthy adults and establish an accurate predictive equation for this population.Methods In total,470 Chinese healthy adults had their BEE measured using the Cosmed K4b2 portable metabolic system.Multiple linear regression analysis was applied to develop new optimal equations for predicting BEE.The bias,accuracy rate,concordance correlation coefficient(CCC),and root mean square error(RMSE)were used to evaluate the accuracy of the predictive equations.Results There was a significant difference in BEE between males and females,with 5,954 kJ/d and 5,089 kJ/d,respectively.People living in rural areas expended significantly higher BEE(5,885 kJ/d)than those in urban areas(5,279 kJ/d).Previous equations developed by Henry,Schofield,Harris-Benedict(HB),and Liu overestimated the BEE of Chinese healthy adults.The new equations derived from the present study displayed the smallest average bias and RMSE from the measured basal energy expenditure(mBEE).The CCC of the new equations was higher than other predictive equations,but it was lower than 0.8.There was no significant difference in the accuracy rate among all predictive equations.Conclusions Sex and regional differences in BEE were observed in Chinese healthy adults.Neither the widely used previous predictive equations nor the one derived in the present study were accurate enough for estimating the BEE of Chinese healthy adults.Further study is required to develop more accurate equations for predicting the BEE of Chinese healthy adults aged between 20–45 years.
基金supported by the National Natural Science Foundation of China(No.81001247)
文摘Objective The goal of this study was to analyze protein requirements in healthy adults through a meta-analysis of nitrogen balance studies. Methods A comprehensive search for nitrogen balance studies of healthy adults published up to October 2012 was performed, each study were reviewed, and data were abstracted. The studies were first evaluated for heterogeneity. The average protein requirements were analyzed by using the individual data of each included studies. Study site climate, age, sex, and dietary protein source were compared. Results Data for 348 subjects were gathered from 28 nitrogen balance studies. The natural logarithm of requirement for 348 individuals had a normal distribution with a mean of 4.66. The estimated average requirement was the exponentiation of the mean of the log requirement, 105.64 mg N/kg·d. No significant differences between adult age, source of dietary protein were observed. But there was significant difference between sex and the climate of the study site(P<0.05). Conclusion The estimated average requirement and recommended nutrient intake of the healthy adult population was 105.64 mg N/kg·d(0.66 g high quality protein/kg·d) and 132.05 mg N/kg·d(0.83 g high quality protein/kg·d), respectively.
基金sponsored by the Young Scholar Scientific Research Foundation of the National Institute of Nutrition and Health of China CDC[Grant No:NINH2016001]
文摘Iodine is an element that is essential for the synthesis of thyroid hormones.Adequate intake of dietary iodine has been recognized as a critical factor for maintaining health[1].It is a well-known fact that iodine deficiency can impede the production of thyroid hormones in both the mother and fetus,which increases the risk of brain damage in the fetal stage.Excess iodine can also result in a series of thyroid dysfunction symptoms such as goiter
基金supported by the National Natural Science Foundation of China [grant number 81330066]
文摘Objective This study is to obtain precise data on iron physiological requirements in Chinese children using single stable isotope tracertechnique.Methods Thirty boys(10.6±0.2 years)and 27 girls(10.4±0.2 years)were received oral 6 mg ^(57)Fe each day for 5 consecutive days.Venous blood samples were subsequently drawn to examine the change of total iron concentration and ^(57)Fe abundance at day 0,14,28,60,90,180,360,450,540,630,720.The iron physiological requirement was calculated by iron loss combined with iron circulation rate once ^(57)Fe abundance stabilized in human body.Results The iron physiological requirement was significantly lower in boys than those values in girls(16.88±7.12 vs.18.40±8.81μg/kg per day,P<0.05).Correspondingly,the values were calculated as 722.46±8.43μg/day for boys and 708.40±7.55μg/day for girls,respectively.Considering nearly 10%iron absorption rate,the estimated average iron physiological requirement was 6.0 mg/day in boys and 6.2 mg/day in girls.Conclusion This study indicate that iron physiological requirement could require more daily iron intake in girls as compare with the values in boys having the same body weight.These findings would be facilitate to the new revised dietary reference intakes.
基金supported by the National Natural Science Foundation of China[GN.81872624]the Sanming Project of Medicine in Shenzhen[SZSM201611017]。
文摘Iodine is an essential component of thyroid hormones’biosynthesis and is crucial for normal growth and healthy development[1].If the amount of dietary iodine intake cannot match the long-term requirement,regardless of whether it is excessively low or high,it can cause various thyroid dysfunctions,including hyperthyroidism,hypothyroidism,and autoimmune thyroid diseases[2].
