Development and Evaluation of Validity of Short Dish Frequency Questionnaire (DFQ) for Estimation of Habitual Sodium Intake for Korean Adults / 대한지역사회영양학회지

The aim of this study was to develop various types of a dish frequency questionnaire (DFQ) for estimating the habitual sodium intake and to evaluate the validity of a 125 item dish frequency questionnaire (DFQ 125) with the DFQ 70, DFQ 36 and DFQ 15. For the DFQ 125, one hundred and twenty five dish items were selected based on the information of sodium content of a one serving size, consumption frequency and dish items that contributed most to the variation of sodium intake. Frequency of consumption was determined through nine categories ranging from more than 3 times a day to almost never to indicate how often the specified amount of each food item was consumed during the past 6 months. The sodium intake estimated with DFQ 125 was 5775.0 +/- 3636.3mg, 12.6% higher than that estimated with a 24 hr urine analysis (5009.7 +/- 1541.9mg) and significant correlation was observed between them (r = 0.3315, p < 0.001). When sodium content in broth leftover was subtracted from the total intake, the actual sodium intakes was decreased to 5309.6 +/- 3076.6mg, which was 3.2% higher than that with a 24-hr urine analysis. Overall, 56% of subjects in the lowest quintile of sodium intake computed with DFQ 125 were also in the lowest of adjacent quintile while categorization into the opposite quintile were 4.9%. DFQ 70 was developed from DFQ 125 by omitting the food items not frequently consumed, selecting the dish items that showed higher sodium content per one portion size and higher consumption frequency. The sodium intake estimated with DFQ 70 (5026.6 +/- 3107.1mg) showed only 0.2% difference from that estimated with a 24-hr urine analysis, significant correlation with it (r = 0.3199, p < 0.001) and higher proportion of subjects to be classified into the same or adjacent quintile. The sodium intake estimated with DFQ 36 or DFQ 15 was also significancy correlated with that estimated with a 24-hr urine analysis (r = 0.3441, p < 0.001; r = 0.321, p < 0.001 respectively) and more. The proportion of subjects was classified into the same or adjacent quintile. However, the actual sodium intake estimated with DFQ 36 or DFQ 15 were 3534.0 +/- 1804.6mg and 2508.0 +/- 1261.5mg, respectively, 31.3% or 51.3% less than that estimated with a 24-hr urine analysis. It seems the DFQ 125 with subtraction of sodium content in broth leftover or DFQ 70 can be used quantitatively to estimate sodium intake of adults. DFQ 36 or DFQ 15 can be used as a screening tool or to assess the changes of sodium intake after nutrition education.

Sodium Intakes of Korean Adults with 24-hour Urine Analysis and Dish Frequency Questionnaire and Comparison of Sodium Intakes According to the Regional Area and Dish Group / 대한지역사회영양학회지

This study was performed to assess the sodium intakes of Korean adults using a 24-hr urine analysis and dish frequency questionnaire (DFQ) according to each dish group and the regional area. The subjects of this study were comprised of 552 adults (male: 267, female: 285), aged 20-59yr residing in the metropolitan area (N = 200), Chungcheng-Do (N = 117), Jeolla-Do (N = 117), and Gueongsang-Do provinces (N = 118). The subjects were recruited from the residents who once participated or are participating in the various health programs offered by the public health center. The number of subjects who completed the 24-hr urine collection was 205 (male : 110, female : 95).The mean age and BMI of the subjects were 39.0+/-11.7 y and 23.1+/-2.9 kg/m2, respectively. The mean systolic and diastolic blood pressure was 119.5+/-15.4 mmHg, and 77.1+/-11.1 mmHg, respectively. Eighteen percent of the subjects responded that they are currently smoking, 36% drinking and 50.4% exercising. Twenty point six percent of the subjects were assessed as having hypertension according to their systolic or diastolic blood pressure(SBP > or = 140 mmHg or DBP > or = 90 mmHg) measurements in the present study. Salt intake of the subject estimated with 24-hr sodium excretion was 12.7 g/d (male : 13.4 g/d, female : 12.1 g/d) based on the sodium excretion rate as 82%. Salt intake estimated with DFQ was 14.7 g/d (male : 16.2 g/d, female : 13.4 g/d), 2 g more than the salt intake estimated with 24-hr urine analysis. The four dish groups that contributed most to the sodium intake in order were kimchi (I1571.4mg), soup and stew (1260.5 mg), fish and shellfish (706.3 mg) and noodle and ramyeon (644.3mg). Salt intake estimated with DFQ was the highest in the subjects of Gueongsang-Do (17.0 g/d), second highest Chungcheong-Do (16.4 g/d) and the lowest in the metropolitan area (13.0 g/d). Subjects of Gueongsang-Do showed the highest sodium intakes in most of the dish group, whereas subjects of the metropolitan area showed the lowest. Residents of Chuncheong-Do revealed the highest sodium intake with kimchi and ofJeolla-Do the higher sodium intake with the main dish (meat, fish and beans). The highest salt percentage of kimchi (3.0+/-0.8%) and soybean paste (14.5 +/-5.1%) were observed in Gueongsang-Do, whereas individuals of the metropolitan area were observed as having kimchi (1.6 +/-0.5%) and soybean paste (7.4 +/-1.6%) with the lowest salt percentage. Men were observed as having more salty kimchi (2.4 +/-0.1%) than women (2.1 +/-0.1%).