• 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.

• Nutrition Research and Practice
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• v.14 no.4
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• pp.384-400
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• 2020

BACKGROUND/OBJECTIVES: Dietary factors are important contributors to cardiometabolic and cancer mortality. We examined the secular trends of nine dietary factors (fruits, vegetables, whole grains, nuts and seeds, milk, red meat, processed meat, sugar-sweetened beverages, and calcium) and the associated burdens of cardiometabolic and cancer mortality in Korea using representative cross-sectional survey data from 1998 to 2016. SUBJECTS/METHODS: Using dietary data from Korean adults aged ≥ 25 years in the Korea National Health and Nutrition Examination Survey (KNHANES), we characterized secular trends in intake levels. We performed comparative risk assessment to estimate the population attributable fraction and the number of cardiometabolic and cancer deaths attributable to each dietary factor. RESULTS: A total of 231,148 cardiometabolic and cancer deaths were attributable to nine dietary risk factors in Korea from 1998 to 2016. Suboptimal intakes of fruits and whole grains were the leading contributors. Although the intakes of fruits, vegetables, and whole grains moderately improved over time, the intake levels in 2016 (192.1 g/d, 225.6 g/d, and 10.9 g/d, respectively) remained far below the optimal levels. Deaths attributable to the low intakes of nuts and seeds (4.5 g/d), calcium (440.5 mg/d), and milk (37.1 g/d) and the high intakes of red meat (54.7 g/d), processed meat (4.7 g/d), and sugar-sweetened beverages (33.0 g/d) increased since 1998. Compared with older age groups (≥ 45 years), more unfavorable changes in dietary patterns were observed in the younger population aged 25-44 years, including more sharply increased intakes of processed meat. CONCLUSIONS: We observed improvement in the intakes of fruits, vegetables, and whole grains and unfavorable changes in the intakes of processed meat and sugar-sweetened beverages over the past few decades. Our data suggest that to reduce the chronic disease burden in Korea, more effective nutritional policies and interventions are needed to target these dietary risk factors.

• Nutrition Research and Practice
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• v.14 no.5
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• pp.501-518
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• 2020

BACKGROUND/OBJECTIVES: Sodium intake is positively associated with blood pressure, which may increase the risk for cardiovascular disease (CVD). Therefore, we assessed the disease burden of CVD attributable to sodium intakes above 2,000 mg/day and prospectively investigated the association between dietary/urinary sodium levels and the risk of all-cause and CVD-mortality using the Korea National Health and Nutrition Examination Survey (KNHNES). SUBJECTS/METHODS: A total of 68,578 and 33,113 participants were included for comparative risk assessment (CRA) analysis and mortality analysis, respectively, and mean follow-up time for mortality was 5.4 years. CRA analysis was used to quantify attributable incidences of stroke, ischemic heart disease (IHD), and deaths attributable to sodium intake between 1998 and 2016. Cox proportional hazard regression model was used to determine the association between sodium intake and all-cause and CVD-mortality. RESULTS: Mean dietary sodium intake decreased over time, reaching 3,647 mg/day in 2016. Similarly, the population attributable fractions of stroke and IHD, and the number of CVD-associated deaths attributable to high sodium intake/excretion also decreased. In terms of association with mortality, when participants were grouped into quartiles (Q) by energy-adjusted sodium intake, those in Q2 had a lower risk of all-cause mortality than those in Q1 with lower intakes. The risk of CVD-associated mortality was higher only in females with high sodium intake in Q4 than those in Q1. CONCLUSIONS: This nationwide data indicates that, in line with previous studies of multiple cohorts, both low and high sodium intakes may be associated with an increased risk of mortality; therefore, the optimal sodium intake for Koreans needs to be revised.

• Nutrition Research and Practice
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• v.14 no.5
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• pp.438-452
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• 2020

BACKGROUND/OBJECTIVES: Brain senescence causes cognitive impairment and neurodegeneration. It has also been demonstrated that curcumin (Cur) and hesperetin (Hes), both antioxidant polyphenolic compounds, mediate anti-aging and neuroprotective effects. Therefore, the objective of this study was to investigate whether Cur, Hes, and/or their combination exert anti-aging effects in D-galactose (Dg)-induced aged neuronal cells and rats. MATERIALS/METHODS: SH-SY5Y cells differentiated in response to retinoic acid were treated with Cur (1 μM), Hes (1 μM), or a combination of both, followed by 300 mM Dg. Neuronal loss was subsequently evaluated by measuring average neurite length and analyzing expression of β-tubulin III, phosphorylated extracellular signal-regulated kinases, and neurofilament heavy polypeptide. Cellular senescence and related proteins, p16 and p21, were also investigated, including their regulation of antioxidant enzymes. In vivo, brain aging was induced by injecting 250 mg/kg body weight (b.w.) Dg. The effects of supplementing this model with 50 mg/kg b.w. Cur, 50 mg/kg b.w. Hes, or a combination of both for 3 months were subsequently evaluated. Brain aging was examined with a step-through passive avoidance test and apoptosis markers were analyzed in brain cortex tissues. RESULTS: Cur, Hes, and their combination improved neuron length and cellular senescence by decreasing the number of β-gal stained cells, down-regulated expression of p16 and p21, and up-regulated expression of antioxidant enzymes, including superoxide dismutase 1, glutathione peroxidase 1, and catalase. Administration of Cur, Hes, or their combination also tended to ameliorate cognitive impairment and suppress apoptosis in the cerebral cortex by down-regulating Bax and poly (ADP-ribose) polymerase expression and increasing Bcl-2 expression. CONCLUSIONS: Cur and Hes appear to attenuate Dg-induced brain aging via regulation of antioxidant enzymes and apoptosis. These results suggest that Cur and Hes may mediate neuroprotective effects in the aging process, and further study of these antioxidant polyphenolic compounds is warranted.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.324-335
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• 2018

BACKGROUND/OBJECTIVES: We examined dietary fat intake and the major food sources by young children in Korea. SUBJECTS/METHODS: A total of 1,041 children aged 1-5 years were identified from the 2013-2015 Korea National Health and Nutrition Examination Survey. Data on total fat and fatty acid intake were obtained by a single 24-h dietary recall. Food sources were identified based on the amounts of total fat and fatty acids consumption according to each food. Fat and fatty acid intakes and their food sources were presented by age group (1-2-y, n = 401; 3-5-y, n = 640). Fat and fatty acid intakes were also evaluated according to socioeconomic characteristics. RESULTS: The mean intake of fat was $27.1{\pm}0.8g$ in the 1-2-y group and $35.5{\pm}0.7g$ in the 3-5-y group, and about 23% of the total energy was obtained from fat in both age groups. The mean intake of saturated fatty acids (SFA) was $10.5{\pm}0.3g$ in the 1-2-y group and $12.7{\pm}0.3g$ in the 3-5-y group, with the 1-2-y group obtaining more energy from SFA than the 3-5-y group (9.2% vs. 8.3%). The mean intake of polyunsaturated fatty acids (PUFA) was $6.3{\pm}0.1g$ in the total subjects, with $0.8{\pm}0.03g$ of n-3 fatty acids and $5.5{\pm}0.1g$ of n-6 fatty acids being consumed. Milk, pork, and eggs were major food sources of total fat, SFA, and monounsaturated fatty acids, and soybean oil was the main contributor to PUFA in both age groups. In the 1-2-y group, children in rural areas had significantly higher intake of PUFA and n-3 fatty acids than did those in urban areas. CONCLUSIONS: Our findings provide current information on dietary fat intake among young Korean children and could be used to establish dietary strategies for improvement of health status.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.336-341
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• 2018

BACKGROUND/OBJECTIVES: Dietary Reference Intakes (DRI) for energy are derived from total energy expenditure (TEE) measured using the doubly labelled water (DLW) method. The objective of this study was to assess the validity of DRI for predicting the energy requirements of elementary school-age children. SUBJECTS/METHODS: The present study involved 25 elementary school-age children aged between 9 and 11 years. TEE was assessed by the DLW method, and the results were compared with the TEE predicted by the DRI equations in order to evaluate accuracy. RESULTS: The subjects' TEE measured by the DLW method was $1,925.2{\pm}380.9kcal/day$ in boys and $1,930.0{\pm}279.4kcal/day$ in girls, whereas resting energy expenditure was $1,220.2{\pm}176.9kcal/day$ in boys and $1,245.9{\pm}171.3kcal/day$ for girls. The physical activity level was $1.58{\pm}0.20$ in boys and $1.55{\pm}0.13$ in girls. The mean bias between the predicted and measured TEE was 12.6% in boys and -1.6% in girls, and the percentage of accurate predictions was 28.6% and 63.6%, respectively. In boys, the equation resulted in underprediction of TEE among the subjects having low TEE values, whereas there was overprediction among subjects having high TEE values as shown by the Bland-Altman plot. On the contrary, this proportional bias was not observed in girls. CONCLUSIONS: The findings of this study suggest that the DRI equation for energy could result in the overestimation of energy requirements in elementary school-age boys. In the case of girls, the equations could be accurate at the group level. However, the DRI appears to be invalid for individual girls, as more than one third of girls had their TEE inaccurately predicted. We recommend more studies for confirmation of these results.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.307-314
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• 2018

BACKGROUND/OBJECTIVES: Numerous researches have studied the association between sugar intake and obesity of children in many countries. This study was undertaken to investigate the association between beverage intake and obesity of children by reviewing a database for total sugar contents established in all foods and presented in a nutrition survey by the Korea National Health and Nutrition Examination Survey (KNHANES). SUBJECTS/METHODS: Data of 1,520 children aged 6-11 years in the 6th KNHANES (2013-2015) were analyzed for this study. A database for total sugar intake comprises the total sugar contents of all foods included in the results of a nutrition survey using the 24-hour recall method of 6th KNHANES. Beverages were categorized into carbonated beverages, fruit & vegetable drinks, other drinks, tea, and coffee. RESULTS: The average daily beverage intake of all children was 131.75 g/day, and the average daily total sugar intake in beverages was 13.76 g/day. Carbonated beverages had the highest intake rate (58.85 g/day) and also ranked highest for sugar intake (6.36 g/day). After adjusting for confounding variables, the odds ratio for obesity in children with beverage intake of ${\geq}200mL/day$ significantly increased by 1.83 times (95% CI, 1.11-3.00) as compared to children with beverage intake of < 200 mL/day. Also, a significant increase was observed in the odds ratio for obesity in total children (2.41 times; 95% CI, 1.35-4.33) and boys (3.15 times; 95% CI, 1.53-6.49) with carbonated beverage intake of ${\geq}200mL/day$ when compared with children who consumed < 200 mL/day. CONCLUSION: A positive association is observed between beverage intake and obesity in Korean children. In particular, an intake of carbonated beverages has a positive correlation with childhood obesity in boys. This study can therefore be used as scientific evidence for reducing sugar, and for the continuous management and research on beverages.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.315-323
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• 2018

BACKGROUND/OBJECTIVES: Available data suggest that seasonal changes may influence the nutritional status and overall health of elderly individuals. Therefore, this study was conducted to investigate the effects of seasonal changes and related factors on energy and nutrient intake of older adults. SUBJECTS/METHODS: Individuals aged 65 years or over were prospectively enrolled in this single-center study (male: 11, female: 20). Data were collected between May 2013 and February 2014 during winter, spring, summer and autumn. Food consumption and biochemical parameters were taken during each season to assess the seasonal nutrition status of the elderly. Upon analysis of biochemical parameters (retinol, vitamin D and vitamin C), an high-performance liquid chromatography device was utilized whereas an Immulite 2000 device was utilized during analysis of serum folic acid and parathyroid hormone. RESULTS: Fruit, fat, egg and bread consumption varied seasonally in males and females (P < 0.05). During winter, daily energy intake was found to be greater than in other seasons in males (557 kcal) and females (330 kcal) (P < 0.05). Additionally, carbohydrates, vegetable protein, n-3 fatty acid and sodium intake increased in winter, while the n-6/n-3 ratio increased in summer among males (P < 0.05). Dietary fiber and sodium intake in winter, vitamin C, iron and zinc intake in spring, and cholesterol, retinol, vitamin D and niacin intake in autumn were found to be higher in females when compared to other seasons (P < 0.05). Serum parathyroid hormone level was higher in winter, and vitamin D level was higher in autumn in both genders (P < 0.05). In males, blood folic acid level was higher in winter, while vitamin C level was higher in females, and there was no seasonal variation in retinol concentration (P < 0.05). CONCLUSION: Food consumption and biochemical parameters showed significant seasonal variations in older adults. It is not clear if nutrition plans in older adults will benefit from consideration of seasonal changes in eating habits.

• Nutrition Research and Practice
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• v.12 no.4
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• pp.275-282
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• 2018

BACKGROUND/OBJECTIVE: There is intense interest in soy isoflavone as a hormone replacement therapy for the prevention of postmenopausal osteoporosis. A new kind of isoflavone-enriched whole soy milk powder (I-WSM) containing more isoflavones than conventional whole soy milk powder was recently developed. The aim of this study was to investigate the effects of I-WSM on bone metabolism in ovariectomized mice. MATERIALS/METHODS: Sixty female ICR mice individually underwent ovariectomy (OVX) or a sham operation, and were randomized into six groups of 10 animals each as follows: Sham, OVX, OVX with 2% I-WSM diet, OVX with 10% I-WSM diet, OVX with 20% I-WSM diet, and OVX with 20% WSM diet. After an 8-week treatment period, bone mineral density (BMD), calcium, alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) 5b, osteocalcin (OC), procollagen 1 N-terminal propeptide (P1NP), and osteoprotegenin (OPG) were analyzed. RESULTS: BMD was significantly lower in the OVX group compared to the Sham group but was significantly higher in OVX + 10% I-WSM and OVX + 20% I-WSM groups compared to the OVX group (P < 0.05). Serum calcium concentration significantly increased in the OVX + 10% and 20% I-WSM groups. Serum ALP levels were significantly lower in the OVX + 10% and 20% I-WSM groups compared to the other experimental groups (P < 0.05). OC was significantly reduced in the OVX group compared to the Sham group (P < 0.05), but a dose-dependent increase was observed in the OVX groups supplemented with I-WSM. P1NP and OPG levels were significantly reduced, while TRAP 5b level was significantly elevated in the OVX group compared with the Sham group, which was not affected by I-WSM (P < 0.05). CONCLUSIONS: This study suggests that I-WSM supplementation in OVX mice has the effect of preventing BMD reduction and promoting bone formation. Therefore, I-WSM can be used as an effective alternative to postmenopausal osteoporosis prevention.

• Nutrition Research and Practice
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• v.12 no.5
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• pp.378-386
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• 2018

BACKGROUND/OBJECTIVES: Benign prostatic hypertrophy (BPH) is a major cause of abnormal overgrowth of the prostate mainly in the elderly. Corni Fructus has been reported to be effective in the prevention and treatment of various diseases because of its strong antioxidant effect, but its efficacy against BPH is not yet known. This study was designed to evaluate the therapeutic efficacy of Corni Fructus water extract (CF) in testosterone-induced BPH rats. MATERIALS/METHODS: To induce BPH, rats were intraperitoneal injected with testosterone propionate (TP). Rats in the treatment group were orally administered with CF with TP injection, and finasteride, which is a selective inhibitor of $5{\alpha}$-reductase type 2, was used as a positive control. RESULTS: Our results showed that the increased prostate weight and histopathological changes in BPH model rats were suppressed by CF treatment. CF, similar to the finasteride-treated group, decreased the levels of testosterone and dihydrotestosterone by TP treatment in the serum, and it also reduced $5{\alpha}$-reductase expression and concentration in prostate tissue and serum, respectively. In addition, CF significantly blocked the expression of the androgen receptor (AR), AR co-activators, and proliferating cell nuclear antigen in BPH rats, and this blocking was associated with a decrease in prostate-specific antigen levels in serum and prostate tissue. CONCLUSIONS: These results suggest that CF may weaken the BPH status through the inactivation of at least $5{\alpha}$-reductase and AR activity and may be useful for the clinical treatment of BPH.