Misung Kim

Relationship between inflammation biomarkers, antioxidant vitamins, and bone mineral density in patients with metabolic syndrome

Few studies have shown the correlation between metabolic syndrome and bone mineral density (BMD). The main pathogenic mechanisms of metabolic syndrome rely on chronic low-level inflammatory status and oxidative stress. There are few studies that examine the gender-specific effects of inflammation and antioxidants on BMD. In this study, we evaluated the relative contribution of these factors in patients with metabolic syndrome. We conducted a cross-sectional study of 67 men and 46 postmenopausal women with metabolic syndrome; metabolic syndrome was defined as having three or more metabolic syndrome risk factors. BMD, body fat mass, and lean body mass were evaluated. We also examined the levels of high sensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), adiponectin, vitamin E, and C in serum. Log-transformed hs-CRP levels were significantly higher in lumbar spine osteoporotic subjects than in normal subjects for women but not for men. There was no significant difference between the normal group and the osteoporotic group in other inflammatory markers. Stepwise regression analyses for BMD of the lumbar spine showed that lean body mass and vitamin E were significant determinants in men. Lean body mass and log-transformed hs-CRP were significant determinants in women Analysis for BMD of the femoral neck showed that lean body mass was a significant determinant for both men and women. There was no significant factor among the inflammatory markers or antioxidant vitamins affecting the femoral neck BMD for either gender. In conclusion, while hs-CRP is an independent predictor of the BMD of the lumbar spine in women, vitamin E showed profound effects on BMD in men but not women with metabolic syndrome.

Correlation between vitamin D and cardiovascular disease predictors in overweight and obese Koreans

Although there is evidence that vitamin D deficiency relates to expression of chronic disease, relationship between vitamin D and cardiovascular disease predictors have not been clearly demonstrated in Korean. Our objective was to assess the correlation between vitamin D and the cardiovascular and inflammatory markers in overweight and obese people who had not been exposed to a particular disease. We enrolled 171 healthy adults (159 men and 12 pre-menopausal women) with no history of cardiovascular disease and with a body mass index >23 kg/m2 in this study. In addition, levels of serum vitamin D and concentrations of the inflammatory markers hs-CRP, interleukin-6, and adiponectin were measured. The average age of our study subjects was 48.53 years old, and 64.8% of all male subjects and 91.9% of all female subjects were in the vitamin D deficient status. Serum vitamin D levels showed a positive correlation with age (p<0.05), HDL-cholesterol (p<0.05), and adiponectin (p<0.05) levels. However, there was a negative correlation of vitamin D with triglyceride (p<0.01) and interleukin-6 levels (p<0.05). In addition, even after adjusting for factors that may affect the cardiovascular index (age, sex, body mass index, smoking, and alcohol intake), serum vitamin D levels showed a significant correlation with triglyceride (p<0.05), HDL-cholesterol (p<0.05), and adiponectin (p<0.05) levels. Therefore, the results of this study suggest that vitamin D may be a predictor of cardiovascular disease for overweight and obese people who are likely to be at a risk for cardiovascular disease.

Relationship between vitamin K status, bone mineral density, and hs-CRP in young Korean women

Vitamin K intake has been reported as an essential factor for bone formation. The current study was conducted under the hypothesis that insufficient vitamin K intake would affect inflammatory markers and bone mineral density in young adult women. The study was a cross-sectional design that included 75 women in their 20s. Physical assessments, bone mineral density measurements, 24-hr dietary recalls, and biochemical assessments for high sensitivity C-reactive protein (hs-CRP) and percentages of undercarboxylated osteocalcin (%ucOC) were performed. An analysis of vitamin K nutritional status was performed comparing first, second, and third tertiles of intake based on %ucOC in plasma. Vitamin K intake levels in the first, second, and third tertiles were 94.88 ± 51.48 µg, 73.85 ± 45.15 µg, and 62.58 ± 39.92 µg, respectively (P < 0.05). The T-scores of the first and third tertiles were 1.06 and -0.03, respectively, indicating that bone mineral density was significantly lower in the group with lower vitamin K intake (P < 0.05). There was a tendency for different serum hs-CRP concentrations between the first (0.04 ± 0.02) and third tertiles (0.11 ± 0.18), however this was not statistically significant. Regression analysis was performed to identify the correlations between vitamin K nutritional status, inflammatory markers, and bone mineral density after adjusting for age and BMI. Serum hs-CRP concentrations were positively correlated with vitamin K deficiency status (P < 0.05). And bone mineral density, which was represented by speed, was negatively correlated with vitamin K deficiency status (P < 0.05). In conclusion, status of vitamin K affects inflammatory status and bone formation. Therefore, sufficient intake of vitamin K is required to secure peak bone mass in young adult women.

Estimation of vitamin K intake in Koreans and determination of the primary vitamin K-containing food sources based on the fifth Korean National Health and Nutrition Examination Survey (2010-2011)

There is little information on dietary vitamin K intake and nutritional status of daily requirements of vitamin K in Korea. The objective of this study was to investigate the vitamin K intake and major food sources of Vitamin K in Koreans. The survey data from the 2010-2011 Korean National Health and Nutrition Examination Survey of 7,792 subjects (aged 19-64 years) were examined. Total vitamin K intake was calculated from 24-hour dietary recall using a vitamin K food database, Computer Aided Nutritional analysis Program and the United States Department of Agriculture database. The geometric mean of vitamin K was estimated as 322.40 ± 6.33 ug/day for men and 271.20 ± 4.92 ug/day for women. Daily vitamin K intake increased significantly with age (p for trend < 0.001). The main food source of vitamin K was vegetables (72.84%), including cabbage kimchi (19.26%), spinach (17.38%), sesame leaves (7.11%), radish leaves (6.65%), spring onions (6.28%), and laver (4.82%), followed by seaweed, seasonings, and fat and oils. We observed that the vitamin K intake of Koreans was relatively higher than that reported by other studies in Western countries and differed depending on age.

Vitamin K1 (phylloquinone) and K2 (menaquinone-4) supplementation improves bone formation in a high-fat diet-induced obese mice

Several reports suggest that obesity is a risk factor for osteoporosis. Vitamin K plays an important role in improving bone metabolism. This study examined the effects of vitamin K1 and vitamin K2 supplementation on the biochemical markers of bone turnover and morphological microstructure of the bones by using an obese mouse model. Four-week-old C57BL/6J male mice were fed a 10% fat normal diet group or a 45% kcal high-fat diet group, with or without 200 mg/1000 g vitamin K1 (Normal diet + K1, high-fat diet + K1) and 200 mg/1000 g vitamin K2 (Normal diet + K2, high-fat diet + K2) for 12 weeks. Serum levels of osteocalcin were higher in the high-fat diet + K2 group than in the high-fat diet group. Serum OPG level of the high-fat diet group, high-fat diet + K1 group, and high-fat diet + K2 group was 2.31 ± 0.31 ng/ml, 2.35 ± 0.12 ng/ml, and 2.90 ± 0.11 ng/ml, respectively. Serum level of RANKL in the high-fat diet group was significantly higher than that in the high-fat diet + K1 group and high-fat diet + K2 group (p<0.05). Vitamin K supplementation seems to tend to prevent bone loss in high-fat diet induced obese state. These findings suggest that vitamin K supplementation reversed the high fat diet induced bone deterioration by modulating osteoblast and osteoclast activities and prevent bone loss in a high-fat diet-induced obese mice.

Dietary intake of vitamin K in relation to bone mineral density in Korea adults: The Korea National Health and Nutrition Examination Survey (2010–2011)

Low vitamin K nutritional status has been associated with increased risk of fracture, however inconsistent results exist to support the role of vitamin K on bone mineral density depending on ethnic difference and gender. Our objective was to determine vitamin K intake in Korean adults, examine correlation between vitamin K intake and bone mineral density. This study analyzed raw data from the fifth Korea National Health and Nutrition Examination Survey for adults (2,785 men, 4,307 women) aged over 19 years. Cross-sectional analyses showed only positive association between vitamin K intake and femur bone mineral density in men after adjusting bone-related factors. However, women in high tertiles of vitamin K intake had a significantly higher bone mineral density both in femur and lumber as compared to women in lowest tertiles (p<0.05). The risk for osteoporosis was decreased as vitamin K intake increased in women, but this effect was not persisted after adjusting factors. The findings of this study indicate that low dietary vitamin K intake was associated with low bone mineral density in subjects. From these results we may suggest an increase in dietary vitamin K intakes for maintaining bone mineral density. (2010-02CON-21-C, 2011-02CON-06-C)

Correlation between Intake of Dietary Fiber and Adherence to the Korean National Dietary Guidelines in Adolescents from Jeonju

This study surveyed dietary intake and adherence to the Korean national dietary guidelines in Korean adolescents. To elucidate basic data for use in nutrition education, which aims to improve adolescent compliance with the national dietary guidelines and to increase the intake of dietary fiber, we evaluated the sources of fiber in adolescent diets. This study included 182 male and 212 female students from 2 middle schools in the Jeonju province. From November 15~20, 2011, we surveyed the students for general characteristics, adherence to the Korean national dietary guidelines, and dietary intake. Dietary fiber intake was 16.57 ± 6.95 g/day for male students and 16.14 ± 7.11 g/day for female students. The food groups that contributed most to dietary fiber intake were (in descending order) cereals, vegetables, seasoning, and fruits. The fiber-containing food items consumed most were cabbage- kimchi, cooked rice, instant noodles, and cabbage. Based on adherence to the Korean national dietary guidelines, the vegetable-based intake of dietary fiber in groups 1 (score 15~45), 2 (score 46~52), and 3 (score 53~75) were 4.41 ± 2.595 g/day, 4.12 ± 2.692 g/day, and 5.49 ± 3.157 g/day, respectively (p<0.001). In addition, the total intake of dietary fiber varied significantly among the three groups (p<0.001) as follows: Group 1, 14.99 ± 6.374 g/day; Group 2, 15.32 ± 6.772 g/day; and Group 3, 18.79 ± 7.361 g/day. In this study, we discovered that adherence to the Korean national dietary guidelines correlates with improved intake of dietary fiber. Therefore, marketing and educational development is needed to promote adherence to the Korean national dietary guidelines. In addition, nutritional education is needed to improve dietary fiber consumption through the intake of vegetables and fruits other than kimchi.

Dietary inflammatory index and its relationship with high-sensitivity C-reactive protein in Korean: data from the health examinee cohort

Inflammation is associated with chronic disease. High-sensitivity C-reactive protein (hs-CRP) is a predictor of chronic disease. The dietary inflammatory index (DII) is used to determine the overall inflammatory potential of diet. A cross-sectional analysis of Health Examinee cohort data (2012–2014) from Korea was performed. Subjects were 40–79 years of age (8,332 males; 19,754 females). The DII was used to analyze the relationship between subject characteristics, nutrient intake, and the hs-CRP. Additionally, the relationship between DII and hs-CRP as a predictor of chronic disease was examined. The DII was divided into 4 quartile: Q1 = −7.21 to −1.88 (median: −3.020), Q2 = −1.87 to −0.02 (median: −0.410), Q3 = −0.01 to 1.87 (median = 0.870) and Q4 = 1.88 to 7.34 (median = 3.040). For each group, the carbohydrate/protein/fat intake ratio was Q1 = 66.7:16.6:19.2, Q2 = 67.2:15.6:18.7, Q3 = 67.3:15.1:18.4 and Q4 = 67.3:14.0:17.9. The odds of elevated hs-CRP were 1.241 times higher in participants with the most proinflammatory diets than those with the most anti-inflammatory diets [hs-CRP; odds ratio (95% confidence interval) for Q4 vs Q1: 1.241 (1.071, 1.438); p for trend = 0.002]. An association was found between a high DII and high levels of hs-CRP. The DII may be applied to measure the association between diet and chronic diseases.

Validity and Reliability of a Self-administered Food Frequency Questionnaire to Assess Vitamin K Intake in Korean Adults.

This study was conducted to validate a food frequency questionnaire (FFQ) to assess vitamin K intake in clinical and research settings based on data from the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V). We collected a subset of data on informative food items using the 24-hour recall method from adults aged 19 to 64 years from KNHANES V. The cumulative percent contribution and cumulative multiple regression coefficients for vitamin K intake from each food were computed. Twenty-five foods items were selected for the FFQ to assess vitamin K intake. The FFQ was validated against intakes derived from a 5-day food record (5DR) (n = 48). To assess the reliability of the FFQ, participants completed the self-administered FFQ (FFQ1) and a second FFQ (FFQ2) after a 6-month period (n = 54). Data were analyzed using Pearsons correlation coefficients, the cross-classification method, and Bland-Altman plots. Mean intakes were similar for vitamin K between the FFQ and dietary records, with significant correlations observed (r = 0.652), and cross-classification analyses demonstrated no major misclassification of participants into intake quartiles. Bland-Altman plots showed no serious systematic bias between the administrations of the two dietary assessment methods over the range of mean intakes. FFQ reliability was high, with a Pearsons correlation coefficient of 0.560. This pilot study shows promising validation and reliability evidence for the use of this FFQ, which is focused on vitamin K intake in adults, as an efficient screening tool in clinical and research settings.

Effect of the Telephone-Delivered Nutrition Education on Dietary Intake and Biochemical Parameters in Subjects with Metabolic Syndrome

As prevalence of metabolic syndrome has rapidly increased over the past decade, lifestyle changes including dietary habits are considered as a therapeutic cornerstone for metabolic syndrome, cardiovascular complications and type 2 diabetes. We evaluated the effectiveness of a telephone-delivered nutrition education to improve metabolic parameters compared with a single-visit with a dietitian in subjects with metabolic syndrome. A total of seventy-one adults who met diagnostic criteria for the metabolic syndrome were randomly assigned to either the single-visit group or the in-depth nutrition education group during a 3-month intervention study period. The in-depth telephone-delivered nutrition education group had an initial visit with a dietitian and additional two telephone counseling during the first 4 weeks of the study periods. Sixty-six subjects completed a 3-month intervention study. The trial examined participants anthropometric changes and dietary intakes as well as changes in the metabolic syndrome factors. At the end of the trial, the in-depth nutrition education group showed significantly higher reduction in weight, body fat and abdominal circumference compared with the other group (p < 0.05). In the in-depth nutrition groups, the prevalence of metabolic syndrome was decreased to 45.5%, while 69.7% of the subjects were metabolic syndrome patients in the single-visit group (p < 0.05). These results demonstrate that the telephone-intervention counseling is a feasible mean to deliver dietary intervention in patients with metabolic syndrome.