## 4 Discussion
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Variables**} & \multicolumn{6}{c}{**Vitamin D Intake per 1 ug/d Increment, Adjusted**} \\ \cline{2-9}  & \multicolumn{3}{c}{**All (\(n=2513\))**} & \multicolumn{3}{c}{**Men (\(n=1145\))**} & \multicolumn{3}{c}{**Women (\(n=1368\))**} \\ \cline{2-9}  & **OR** & **(95\% CI)** & \(p\)-Value** & **OR** & **(95\% CI)** & \(p\)-Value** & **OR** & **(95\% CI)** & \(p\)-Value** \\ \hline Abdominal obesity & 1.020 & (0.999 1.043) & 0.067 & 1.028 & (1.001 1.051) & 0.043 & 0.980 & (0.951 1.010) & 0.193 \\ Increased BP & 0.994 & (0.972 1.015) & 0.563 & 0.992 & (0.966 1.019) & 0.559 & 0.997 & (0.970 1.025) & 0.821 \\ High blood glucose & 1.012 & (0.995 1.029) & 0.176 & 1.021 & (0.996 1.047) & 0.099 & 0.989 & (0.964 1.016) & 0.427 \\ Increased TG & 0.984 & (0.968 1.001) & 0.072 & 0.980 & (0.961 0.999) & 0.041 & 0.993 & (0.967 1.020) & 0.597 \\ Decreased HDL-C & 1.004 & (0.988 1.019) & 0.656 & 0.997 & (0.972 1.023) & 0.836 & 1.010 & (0.985 1.036) & 0.435 \\ Metabolic syndrome & 1.012 & (0.991 1.033) & 0.275 & 1.005 & (0.978 1.033) & 0.105 & 1.014 & (0.987 1.041) & 0.308 \\ \hline \hline \end{tabular} The information was presented as odds ratio (OR) and 95% confidence intervals (CIs). Adjusted \(p\)-values were derived by a complicated sampling design multivariate logistic regression analysis, adjusted with sex, age, education, occupation, region, drinking, smoking, physical activity, dietary supplement, season of blood draw, intake of saturated fatty acid, polyunsaturated fatty acid, fiber, energy, and BMI (except for analyzing abdominal obesity). Abbreviation: HDL, high-density lipoprotein. Metabolic Syndrome was determined by having 3 or more risk determinants among abdominal obesity (waist circumference greater than 90 cm for men and greater than 85 cm for women), high blood pressure (systolic \(\geq\) 130 mmHg or diastolic \(\geq\) 85 mmHg), high fasting blood glucose of \(\geq\)100 mg/dL, high serum triglycerides of \(\geq\)150 mg/dL, or low HDL (<40 mg/dL for men and <50 mg/dL for women).  
\end{table} 
Table 6: Odds ratios for metabolic syndrome and its components by vitamin D intake. Therefore, in order to examine the more direct relationship between vitamin D level (either serum level or dietary intake) and MetS, we controlled for some factors related to metabolic profiles such as BMI, total energy intake, dietary fiber intake, SFA intake, and PUFA intake, in addition to the usual factors such as sex, age, education, occupation, living area, smoking, alcohol drinking, physical activity, dietary supplement, and the season of blood draw in this study. The odds ratio for MetS components to the serum 25(OH)D concentration revealed that serum 25(OH)D was negatively correlated with abdominal obesity and increased TG in men, implying that vitamin D has a beneficial impact on lowering serum TG, abdominal obesity, and hypertriglyceridemia in Korean adults, particularly Korean men. There are continuous reports of vitamin D and other associations with cholesterol and TG, both of which are diagnostic indicators of dyslipidemia [51; 52; 53; 54]. A novel finding in our study is a negative link between the dietary vitamin D intake and serum LDL cholesterol levels only in Korean women, although they did not show a significant association of serum 25(OH)D concentration with MetS or its components and a weak but positive relationship between vitamin D intake and serum 25(OH)D.  
Similar to our study, the Qatar women's study and other studies found an inverse relationship between the MetS prevalence and serum 25(OH)D level, but no relationship between the serum 25(OH)D level and other Mets components, such as waist circumference, blood pressure, HbA1c, blood glucose, HDL cholesterol, and serum TG [55]. A study reported that dietary vitamin D intake and serum 25(OH)D levels were found to be inversely and significantly related to visceral adipose tissue, as well as the total adipose tissue and BMI.