• Korean Journal of Community Nutrition
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• v.26 no.2
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• pp.103-110
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• 2021

Objectives: The objective of this study was to develop a zinc database (DB) to estimate the intake levels of zinc in Korean toddlers and preschool children using the data from the Korea National Health and Nutrition Examination Survey (KNHANES). Methods: A total of 3,361 food items for the DB representing the usual diet of Korean toddlers and preschool children were selected based on KNHANES (2009~2013) and the food composition table of Rural Development Administration (RDA). The existing values of zinc in foods were collected from the latest food composition tables of RDA (9th revision) and the US Department of Agriculture (legacy release). The zinc contents were filled preferentially with these collected values. The missing values were replaced with the calculated values or imputed values using the existing values of similar food items from the data source. The zinc intake levels of Korean toddlers and preschool children were estimated using KNHANES and zinc DB Results: A total of 1,188 existing values, 412 calculated values, and 1,727 imputed values were included in the zinc DB. The mean intake levels of zinc for 1-2-year-old children and 3-5-year-olds were 5.17 ± 2.94 mg/day and 6.30 ± 2.84 mg/day, respectively. There was no significant difference in the zinc intake levels between boys and girls in each group. Conclusions: This newly developed zinc DB would be helpful to assess the zinc nutritional status and investigate the association between the zinc intakes and related health concerns in Korean toddlers and preschool children.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.35-41
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• 1997

The pancreas is an important organ in the maintenance of zinc homeostasis. Endogenous zinc is con-tinuously secreted via pancreatic exocrine fluid or to a lesser extent in bile. Much of the endogenous secretion must be reabsorbed to sustain zinc homeostasis. The objective of this study was to estimate the relative size of the pancreatic/biliary zinc pool in comparision to the dietary zinc intake, and to study the effect of the phytate and calcium on the zinc homeostasis using a rat model. At the termination of the experiment, pan-creatic/biliary fluid was collected from the rats. Both radioactivity and total zinc were measured and the relative size of the pancreatic/biliary zinc pool was estimated. To determine the effect of phytate and calcium on zinc homeostsis, dietary zinc intake, the amount of zinc in pancreatic.biliary fluid and fecal zinc excretion were measured. The flow rate of pancreatic/biliary fluid, as corrected for tubing constriction, gives the corrected zinc concentration in the pancreatic/biliary fluid was 2.2 times higher than dietary zinc intake. To maintain zinc homeostasis, zinc absorption/reabsorption was very efficient in the current model; 76%, 88% of absorption/reabsorption for low calcium group and high calcium group 81% for phytate group and non-phytate group, respectively.

• Nutrition Research and Practice
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• v.14 no.4
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• pp.365-373
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• 2020

BACKGROUND/OBJECTIVES: To assess the longitudinal associations of the antioxidant capacity of zinc and body mass index (BMI) with serum uric acid (SUA) in South Korean children. SUBJECTS/METHODS: Using follow-up data from the Ewha Birth and Growth Cohort, we included subjects who were seen at 3 and 7 years of age (n = 183; 90 boys, 93 girls). Daily zinc intake and BMI were assessed at 3 and 7 years of age. SUA measured at 7 years was used as the outcome variable. Using a general linear model, the effects of dietary zinc intake and BMI on SUA were assessed. We also assessed the combined effect of early dietary zinc intake and BMI on SUA in children. RESULTS: The dietary zinc intake at 3 years of age was negatively correlated (ρ = -0.18, P = 0.04), whereas the BMI at 7 years of age was positively correlated (r = 0.18, P = 0.01), with the SUA level at 7 years of age. The dietary zinc intake level at 3 years of age and the BMI level at 7 years of age were, together, significantly related to SUA in children at 7 years of age. SUA was lower in group 1 (normal-weight, high-zinc group) than in the other two groups (group 2: normal-weight, low-zinc and overweight, high-zinc group; and group 3: overweight, low-zinc group). Our results demonstrate the combined effect of zinc intake and BMI on SUA. The combined association remained significant in both the crude and adjusted models (P < 0.01). CONCLUSIONS: SUA was related to combined BMI and dietary zinc intake, and increased zinc intake and normal body weight had a beneficial effect on reducing SUA in children.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.4
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• pp.542-549
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• 1995

This study was conducted to obtain accurate data on intake, excretion, apparent digestibility and balance of zinc which Korean take in habitually. This study applied to the seven high school girls from 15 to 16 years old. Their food intake, feces and urine were collected and intake and excretion of zinc in them were measured by atomic absorption spectrophotometry. The measurement continued for four weeks while they maintained their normal living pattern and body weight. Each girl's daily intake and excretion of zinc were measured and apparent digestibility and balance were also studied. Each girl's daily mean intake, fecal excretion and apparent digestibility of zinc were $9.26{\pm}2.30mg,\;3.31{\pm}2.15mg,\;and\;62.92{\pm}3.22%$, respectively. The urinary excretion of zinc was $3.23{\pm}1.03mg$ and showed the positive balance of $2.61{\pm}2.91mg$.

• Journal of Nutrition and Health
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• v.57 no.4
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• pp.365-375
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• 2024

Purpose: Zinc is involved in regulating homeostasis and metabolism in the body, and understanding these processes is important for estimating intake requirements. This review aimed to assist in setting the standards for Dietary Reference Intakes for Koreans (KDRIs, 2025) for zinc by examining specific factors associated with role of zinc in the body and using the factorial analysis method. Methods: We reviewed the zinc-specific factors that should be considered when setting the required zinc intake to maintain zinc homeostasis in the body and used the factorial analysis method for estimating zinc requirements for different population groups. Results: Factorial analysis involves estimating the required intake based on various factors that affect zinc metabolism and requirements. The key components and steps involved in determining the zinc dietary reference intake (DRI), particularly the estimated average requirement (EAR), include: 1) Estimating basal requirements, which involves calculating the amount of zinc needed to replace natural losses through the intestinal (feces) and non-intestinal (urine, skin and other body secretions) routes, 2) Accounting for the various biomarkers related to metabolic functions of zinc, 3) Considering physiological requirements for zinc, such as those for growth, development, pregnancy, and lactation since zinc is essential for DNA and protein synthesis, and 4) Estimating the dietary absorption rate of zinc. Conclusion: The factorial analysis for zinc requirement is based on scientific evidence and is tailored to meet the requirements of different population groups, ensuring optimal health and preventing deficiency. It includes considerations of physiological needs, dietary absorption, and population-specific characteristics.

• Journal of Nutrition and Health
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• v.33 no.8
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• pp.848-856
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• 2000

The study was designed to assess the zinc nutritional status by gestational age of pregnant women visiting in public health centers in Ulsan. The subjects were divided into 3 trimester by last menstrual period(LMP). Interview for dietary zinc intake and general characteristics of each subjects was given and biochemical analysis of blood and urine was performed. Serum zinc concentration and urinary zinc excretion were analyzed by Flame Atomic Absorption Spectrophotometer, and alkaline phosphatase(ALP) activity was analyzed by Bowers & McComb\\`s method with Schimadzu automatic analyser. Also urinary creatinine was analyzed by Hawk\\`s method. Mean intake of zinc was 6.61${\pm}$1.57mg and did not meet the RDA(44.1% of RDA) for pregnant women by gestational age. Zn intake of 3rd trimester was significantly increased but dietary zinc was almost supplied with cereal and grain (47.30%) which were reported with low zinc availability due to phytate. Mean concentration of serum Zn in 1st trimester was 86.4${\pm}$10.5$\mu\textrm{g}$/dl, was 72.4${\pm}$10.3$\mu\textrm{g}$/dl in trimester and 65.1${\pm}$10.8$\mu\textrm{g}$/dl in 3rd trimester and was declined significantly by gestational age during pregnancy. In was concluded that a decline in serum Zn by gestional age was not influenced by amount of Zn intake. However ALP activity and urinary zinc excretion increased significantly by gestational age. Zinc nutritional status of pregnant women was not confirmed yet due to the physiological changes during pregnancy. However, the pregnant woman may be in a marginal zinc deficient status because of low amount of Zn intake and low bioavailability of Zn from dietary sources. (Korean J Nutrition 33(8) : 848-856, 2000)

• Korean Journal of Community Nutrition
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• v.3 no.1
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• pp.12-20
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• 1998

In this study, the food intake, feces and urine of 14 primary school age boys and girls were collected and intake and excretion of iron and zinc were measured. The boys and girls were 8-12 years old and measurement continued for four weeks during which they maintained their normal living pattern. Each boy's and girl's daily intake and excretion of iron and zinc were measured and apparent digestibility and balance were also calculated. The results are as follows. Mean daily intake of iron was $14.9\pm{0.6mg}$ for the boys and $12.4\pm{0.5mg}$ for the girls. Mean daily intake of zinc was $11.8\pm{1.2mg}$ for the boys and $11.5\pm{0.4mg}$ for the girls. Mean daily fecal loss and apparent digestibility of iron was $6.1\pm{0.3mg}$ and $58.8\pm{2.0%}$ for the boys and $6.8\pm{0.1mg}$ and $44.1\pm{2.0%}$ for the girls. Mean daily fecal loss and apparent digestibility of zinc was $9.3\pm{0.2mg}$ and $14.4\pm{5.1%}$ for the boys and $9.7\pm{0.4mg}$ and $14.3\pm{4.3%}$ for the girls. Mean daily urinary loss of iron was $1.1\pm{0.1mg}$ and showed the positive balance of $7.86\pm{0.6mg}$ for the boys and $0.5\pm{0.1mg}$ and showed the positive balance of $5.14\pm{0.4mg}$ for the girls. Mean daily urinary loss of zinc was $0.5\pm{0.1mg}$ and showed the positive balance of $1.03\pm{0.6mg}$ for the girls.

• Journal of Nutrition and Health
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• v.31 no.4
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• pp.756-766
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• 1998

The objectives of this study were to examine the growth pattern and hair trace element contents of healthy infants who were fed breast milk(BF infant) and formula (FF infant) during the first 6 months and its relationship to intake of trace elements. Bimonthyl anthropometric measurements were obtained on 32 infants through 6 months of age. Mean calculated energy, iron, zinc and copper intake from breast milk at 2 months of age were 432.4kcal/d, 0.19mg/d, 1.18mg/d and 0.22mg/d. The values obtained from formular were543.7kcal/d, 6.68mg/d , 2.82mg/d and 0.33mg/d , respectively. In spite of the significantly lower intake of energy and trace elements in BF infants than in FF infants, BF infants showed growth above the average Kroean infant standard growth rate and showed no significant growth rate difference or hair trace element content. Hair iron content in the BF infants at 6 mo. of age was positively related to birth weight and iron intake at 2 mo. of age. In contrast, hair zinc and copper content in the FF infants at 6 mo. of age as negatively related to height increment and weight increment during 6 months, respectively. These results support the suggesting that BF infant's higher iron, zinc and copper intake is attributed to the superior bioabailability of these trace elements from breast milk.

• Corrosion Science and Technology
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• v.7 no.6
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• pp.328-331
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• 2008

Corrosion behaviour of water intake gate steel structures with different protective measures was investigated. Five material alternatives were taken for investigation, including: imported and recycled stainless steel, carbon steel with hot zinc spraying, painting and composite coatings. Results of corrosion rate for carbon steel, SUS 304, hot zinc spray coats in three water systems of Mekong river basin (saline, blackish and fresh) were also presented. Corrosion rate of carbon steel decreased with decreasing salinity in the investigated water environments. Meanwhile, these values for zinc coated steel, behaved by another way. Environmental data for these systems were filed and discussed in relation with corrosion characteristics. Method of Life Cycle Assessment (LCA) was applied in materials selection for water intake gate construction. From point of Life Cycle Cost (LCA) the following ranking was obtained: Zinc sprayed steel < Recycled stainless steel < Composite coated steel < Painting steel < SUS 304 From investigated results, hot zinc spray coating has been applied as protective measure for steel structures of water intake systems in Mekong river basin.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.346-353
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• 1995

The dietary requirement for zinc to maintain optimally the various metabolic and physiological funcitons is still under study. Human beings adapt to reductions in zinc intake by reducing the rate of growth or zinc excretion. Reductions in dietary zinc beyond the capacity to maintain homeostasis lead to utilization of zinc from an exchangeable pool. Loss of a small, critical amount of zinc from this pool leads to both biochemical and clinical signs of zinc deficiency. Zinc requirements have been assessed by balance studies and factorial method. As tissue zinc status influences endogenous losses and the dietary needs, individuls in good status may require higher amounts of zinc than those in poor status. While plasma zinc is insensitive to reducitons in dietary zinc, it is regarded as a valid, useful indicator of the exchangeable pool of zinc. Plasma metallothionein concentrations may prove useful for identifying poor zinc status. It has been suggested that functional end point measurement is the new direciton for zinc requirement. However, determination of the functional response to a marginal zinc intake is difficult because of the lack of a specific, sensitive indicator of zinc status. Presently, no good method for assessment of human zinc requirements exists.