• Nutrition Research and Practice
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• 제16권6호
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• pp.775-788
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• 2022

BACKGROUND/OBJECTIVES: The prevalence of vitamin D deficiency in Koreans is quite high; however, until recently, Korean National Health and Nutrition Survey (KNHANES) had not analyzed the vitamin D intake among Koreans. Additionally, the Korean Dietary Reference Intake for vitamin D was established based on insufficient evidence. Therefore, we investigated vitamin D intake and its relationship with bone mineral density (BMD) in Korean adults using the combined data from the 2009-2011 KNHANES. MATERIALS AND METHODS: This study was conducted in 11,949 healthy adults. Vitamin D intake was assessed using a 24-h recall method, and the BMD was measured using dual-energy X-ray absorptiometry. RESULTS: The prevalence of vitamin D deficiency (< 20 ng/mL) was 64% in men and 77% in women. In women aged ≥ 50 yrs and men aged < 50 yrs, there was a significant positive correlation between vitamin D intake and serum 25-hydroxyvitamin D level after sun exposure adjustment. The BMD of postmenopausal women aged ≥ 50 yrs with a vitamin D intake of 5 ㎍/day or more was significantly higher than that of women with intake less than 5 ㎍/day. After adjusting for age, energy, and calcium intake, the vitamin D intake of the osteoporotic group was significantly lower than that of the osteopenia group in women. CONCLUSIONS: Since the relationship between vitamin D intake and BMD was observed in women aged ≥ 50 yrs, further research is needed to clarify these findings using cohort or randomized controlled trials.

• Nutrition Research and Practice
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• 제13권2호
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• pp.115-125
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• 2019

BACKGROUND/OBJECTIVES: Vitamin D plays an important role in skeletal growth and maintenance and in the prevention of various diseases. We investigated the relationship between vitamin D intake and bone mineral density (BMD) in Korean adults aged ${\geq}50$ years using the 2009 Korea National Health and Nutrition Examination Survey data. SUBJECTS/METHODS: This study was conducted in 1,808 subjects aged ${\geq}50$ years with BMD data in Korea. Dietary vitamin D levels were assessed by the 24-hour recall method. BMD was measured using dual-energy X-ray absorptiometry. We investigated general characteristics and the association between these characteristics, vitamin D status, and BMD. RESULTS: Vitamin D intake was significantly lower in the osteoporosis group among women (P < 0.05). Among all subjects, the higher the serum 25(OH)D concentration, the higher the whole-body total BMD (WBT-BMD), femoral total hip BMD, and femoral neck BMD (P < 0.01). In the serum vitamin D-deficient group of both the total population and women, serum 25(OH)D concentration was associated with WBT-BMD (P < 0.05). Among women with a calcium intake < 537.74 mg/day, BMD of those with a vitamin D intake > $2.51{\mu}g/day$ (average intake of women) was higher than that of women with a vitamin D intake ${\leq}2.51{\mu}g/day$ (P < 0.001). CONCLUSIONS: Korean adults should increase their BMD by increasing serum 25(OH)D concentration. Furthermore, increasing vitamin D intake could improve BMD, especially in Korean women who consume less calcium than the estimated average requirement.

• Nutrition Research and Practice
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• 제15권4호
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• pp.492-503
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• 2021

BACKGROUND/OBJECTIVES: Recently, the recommended nutrient intakes (RNI) for vitamin D for Malaysian aged 1-70 yrs has been revised from 5 ㎍/day to 15 ㎍/day. This study is aimed to assess the adequacy of vitamin D intake based on revised RNI and to recommend several dietary strategies to increase total vitamin D intake. SUBJECTS/METHODS: Vitamin D intake from both food and supplement of 217 pregnant women was assessed using a validated food frequency questionnaire. Hypothetical effect of expanded supplementation and food fortifications strategies were modelled using the consumption data. RESULTS: The results revealed that more than half (67.7%) of pregnant women had inadequate vitamin D intake (RNI < 15 ㎍/day). The modelling results demonstrated the potential of universal provision of 10 ㎍/day of multivitamins supplements in increasing vitamin D intake. Moreover, mandatory fortification of both milk and malted drink at single level of 5 ㎍/serving would lead to increase in vitamin D intake of Malaysians, particularly pregnant women. CONCLUSIONS: The outcome of this study can be used as a reference for public health professionals to re-evaluate the existing Malaysian food fortification policies and supplementation recommendation for vitamin D for pregnant women.

• 대한지역사회영양학회지
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• 제20권2호
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• pp.120-128
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• 2015

Objectives: The purpose of this study was to examine the relative impact of seasonal differences and age on dietary vitamin D intakes, outdoor activity time and serum vitamin D status among Korean postmenopausal women. Methods: A cross-sectional study was conducted with 164 free-living postmenopausal women (mean age=55.4 years) in Daegu, Korea. Dietary intake, daily physical activity patterns and fasting blood samples were collected during summer and winter. We compared the results from 75 women during summer and 89 women during winter. Dietary intake of vitamin D was assessed by 24-hour recall method. Daily outdoor activity time was derived from physical activity diary. Results: The average dietary intake of vitamin D of the participants was $3.7{\mu}g$ during summer, $3.3{\mu}g$ during winter, showing no significant difference between the two seasons. The average time spent on outdoor activities was not significantly different between summer ($=35.1{\pm}75.0min/d$) and winter ($=48.5{\pm}76.8min/d$). The average serum 25-(OH) vitamin D concentrations of participants was $17.5{\pm}7.5ng/mL$ in the summer and $13.4{\pm}4.3ng/mL$ in the winter, showing no significant differences by season. Dietary intake of vitamin D was not related to age. When total subjects were divided into two groups by age, the average serum 25-(OH) vitamin D concentration was significantly higher in older group (p=0.047) and time spent on outdoor activities was also (p=0.018) significantly higher in the older group. Conclusions: In order to improve the current vitamin D status of Korean postmenopausal women, nutrition education programs should focus more on adequate intake of vitamin D, while maintaining enough outdoor activities over the season.

• Nutrition Research and Practice
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• 제16권sup1호
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• pp.57-69
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• 2022

BACKGROUND/OBJECTIVES: Vitamin D is produced in the skin during sun exposure and is also ingested from foods. The role of vitamin D needs to be considered in the prevention and management of various diseases. Moreover, since the majority of Koreans spend their days indoors, becoming susceptible to the risk of vitamin D deficiency. The current study aims to prepare a basis for determining dietary reference intake of vitamin D in Korea, by reviewing the evidence against various diseases and risks. MATERIALS/METHODS: Literature published in Korea and other countries between 2014 and 2018 was prioritized based on their study design and other criteria, and evaluated using the RoB 2.0 assessment form and United States Department of Agriculture Nutrition Evidence Library Conclusion Statement Evaluation Criteria. RESULTS: Of the 1,709 studies, 128 studies were included in the final systematic analysis after screening. To set the dietary reference intakes of vitamin D based on the selected articles, blood 25(OH)D levels and indicators of bone health were used collectively. Blood vitamin D levels and ultraviolet (UV) exposure time derived from the Korean National Health and Nutrition Examination Survey were analyzed to establish the dietary reference intakes of vitamin D for each stage of the life cycle. The adequate intake levels of vitamin D, according to age and gender, were determined to be in the range of 5-15 ㎍/day, and the tolerable upper intake level was established at 25-100 ㎍/day. CONCLUSIONS: The most important variable for vitamin D nutrition is lifestyle. A balanced diet comprising foods with high contents of vitamin D is important, as is vitamin D synthesis after UV exposure. The adequate intake level of vitamin D mentioned in the 2015 Dietary Reference Intakes for Korean (KDRI) remained unchanged in the 2020 KDRI for the management of vitamin D nutrition in Koreans.

• Clinical and Experimental Pediatrics
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• 제52권10호
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• pp.1082-1089
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• 2009

Vitamin D is an important fat-soluble vitamin that functions as a prohormone and affects bone mineralization and calcium homeostasis. Vitamin D deficiency causesboth musculoskeletal manifestations, including rickets, and extra-musculoskeletal symptoms. Because vitamin D is naturally present in only some foods, intake of daily foods cannot meet the dietary reference intake for vitamin D. Sunlight is the main source of vitamin D in humans therefore, the lack of sunlight can easily cause vitamin D deficiency in children and adolescents. Vitamin D deficiency can be diagnosed on the basis ofits typical clinical manifestation, laboratory tests, and radiologic findings. Detection of vitamin D deficiency in children or adolescents necessitates the simultaneous administration of vitamin D and calcium supplements. To prevent vitamin D deficiency, 200 IU of daily vitamin D intake is recommended in infants, and 400 IU of daily vitamin D intake is recommended in Korean children and adolescents.

• Nutritional Sciences
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• 제7권2호
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• pp.98-106
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• 2004

The dietary vitamin $B_6$ intake of 185 Korean children aged 7-12 years (y), who showed no health problems, in the Seoul area and its sources were estimated using a modified Korean vitamin $B_6$ database. The age and sex of each subject was classified according to the classifications in the Korean Recommended Dietary Allowance (RDA). Dietary vitamin $B_6$ intake and food sources were estimated using the three-day recall method with the help of a trained interviewer. Food portion sizes were estimated by using standard household measures and published average portion sizes. The average daily vitamin $B_6$ intake was 1.69$\pm$0.50 mg/d in children aged 7-9 y, 1.86$\pm$0.44 mg/d in male children aged 10-12 y and 1.77$\pm$0.62 mg/d in female children aged 10-12 y. Less than 5% of the subjects consumed less than the Korean RDA of vitamin $B_6$. The average ratio of vitamin $B_6$intake to daily protein intake was 0.028$\pm$0.006 mg/g in children aged 7-9 y, 0.028$\pm$0.004 mg/g in male children aged 10-12 y and 0.029$\pm$0.007 mg/g in female children aged 10-12 y. The intake of vitamin $B_6$ was significantly (p<.01) positively correlated to the intake of all other nutrients. Foods from animal and plant sources provided 37% and 73% respectively, of total vitamin $B_6$. Major dietary sources of vitamin $B_6$ in children in the Seoul area were rice, soybean sprouts, pork, beef, cereal, kimchi, milk, onions, and potatoes. As for major dietary sources of vitamin $B_6$, the top 20 foods provided nearly 73-75% of the total vitamin $B_6$ consumed by Korean children.

• 대한지역사회영양학회지
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• 제19권3호
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• pp.231-240
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• 2014

Objectives: This study was intended to examine the seasonal differences in outdoor activity times and dietary vitamin D intakes, and explicates their relative impact on improving serum 25-(OH) vitamin D status among Korean young women. Methods: A cross-sectional study was conducted with 135 free-living women aged 19-39 years in Daegu-Kyungbook, Korea. We compared the results from 52 women for the summer and 83 women for the winter. Dietary intake of vitamin D was assessed by 24 hour recall method for non-consecutive three days as well as by food frequency method. Daily outdoor activity times were derived from 24 hour physical activity diary. Results: The average dietary intake of vitamin D of the participants by 24 hour recall method was 3.1 ${\mu}g$ during the summer, 3.3 ${\mu}g$ during the winter, showing no significant difference between the two seasons. Times spent on outdoor activities (p < 0.01) in the summer (= $23.8{\pm}23.6$ min) were much longer than that in the winter (= $10.8{\pm}13.4$ min). The serum 25-(OH) vitamin D levels of participants were $17.5{\pm}7.5$ ng/mL in the summer and $13.4{\pm}4.3$ ng/mL in the winter, showing that the latter was significantly lower than that of the former (p<0.001). The serum 25-(OH) vitamin D levels of subjects were positively related to outdoor activities (r=0.315, p<0.05) during the summer, while related to dietary intake (r=0.252, p<0.05) during the winter. Conclusions: In order to improve the current vitamin D status of Korean young women, nutrition education programs should focus on increasing more dietary intake especially during the winter, and performing more outdoor activities in other seasons.

• Journal of Dairy Science and Biotechnology
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• 제27권2호
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• pp.17-23
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• 2009

In the light of the increasing concern over the prevalence of osteoporosis, hypertension, diabetes mellitus, we performed this study to review the correlation between the dietary calcium and vitamin D intake and these diseases. To this end, we investigated the effects of dietary calcium and vitamin D on these diseases. We observed that the intake of dietary calcium and vitamin D had a negative correlation with the incidences of osteoporosis, hypertension, and diabetes mellitus. Further, the intake of these two nutrients is expected to improve related mechanisms such as the renin-angiotensin system. Therefore, we suggest that dietary calcium and vitamin D have a beneficial effect on these diseases.

• Journal of Nutrition and Health
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• 제49권6호
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• pp.437-446
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• 2016

본 연구는 국민건강영양조사 5기의 2011년 자료를 이용하여 만 19세 이상 남녀를 대상으로 비타민D 섭취량과 혈중 25OHD 농도, 골밀도와의 관계를 분석하였다. 평균 비타민D 섭취량은 남성이 $3.84{\pm}0.23{\mu}g/day$, 여성은 $2.22{\pm}0.11{\mu}g/day$로 나타났으며, AI 미만 섭취 비율은 남성은 71.6~96.6%,여성은 80.2~98.5%로 모두 높게 나타났으며 여성이 남성에 비해 더 높았다. 혈중 25OHD 농도는 연령이 높아질수록 증가했으며, 혈중 25OHD의 결핍수준을 20 ng/mL 미만으로 보았을 때 남성은 47.8~81.1%, 여성은 59.4~92.8%의 결핍률을 보였고 젊은 층의 결핍률이 더 높았다. 50세 미만과 이상으로 나누어 비타민D 섭취량과 혈중 25OHD 농도, BMD와의 관계를 조사한 결과 50세 미만 연령층군에서는 비타민D 섭취량이 $10{\mu}g/day$ 이상인 군이 $5{\mu}g/day$ 이하인 군에 비하여 유의하게 혈중 25OHD 농도가 더 높았으며, 50세 이상 여성에서는 비타민D 섭취량이 $10{\mu}g/day$ 이상인 군이 $5{\mu}g/day$ 이하인 군에 비하여 골밀도가 유의하게 높게 나타났다. 즉, 한국 성인 남녀의 비타민D 섭취량 수준은 상당히 취약한 상태이나 식사를 통한 비타민D가 혈중 25OHD 농도를 상승시킬 수 있음을 보여주고 있다. 그러므로 한국인이 비타민D 섭취량을 늘릴 수 있도록 강화식품 정책 등을 통해 비타민D 섭취량을 늘리는 방안을 모색하여야 한다. 특히, 2010년에 비해 2015년 한국인영양소섭취기준에서 19~49세 연령층의 비타민D 충분섭취량을 $5{\mu}g$에서 $10{\mu}g$으로 상향조정한 것은 바람직한 방향으로 개정된 것으로 판단된다.