ABSTRACT
This study assesses the sodium intake of adults by 24-hour urine analysis, dietary records review and a food intake questionnaire. Subjects were 236 adult female in Daegu. The results are summarized as follows: Sodium intake as indicated by the 24-hour urine analysis was 5,805.4 +/- 3836.8 mg. This was significantly higher than intake indicated by dietary records (4415.4 +/- 1935.1 mg) and the dish frequency questionnaire (DFQ 55)(4293.5 +/- 1526.5 mg). The results of the 24-hour urine analysis and DFQ 55 showed that sodium intake was higher for the 65-to-74-year-old age group than for other age groups (p < 0.05, p < 0.05). Review of dietary records to examine typical sodium intake by food groups showed that 53.7% of the sodium consumed by subjects in all age groups came from seasonings and spices (2399.0 +/- 1526.5 mg). The analysis of sodium intake by food groups using DFQ 55 showed 34.2% of their sodium came from consumption of kimchi (p < 0.001) and kimch, soup, stew and fish jorim accounted for 57.8% of total sodium intake. The results indicate positive correlation between age and sodium intake, as shown by the 24-hour urine analysis and food intake questionnaire (p < 0.05). Therefore, these results would be valuable as basic data for planning nutrition education for sodium intake reduction.
Subject(s)
Adult , Female , Humans , Diet Records , Eating , Porphyrins , Surveys and Questionnaires , Seasons , Sodium , SpicesABSTRACT
The assessment of sodium intake is complex because of the variety and nature of dietary sodium. This study intended to develop a dish frequency questionnaire (DFQ) for estimating the habitual sodium intake and a short DFQ for screening subjects with high or low sodium intake. For DFQ112, one hundred and twelve dish items were selected based on the information of sodium content of the one serving size and consumption frequency. 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. One hundred seventy one adults (male: 78, female: 93) who visited hypertension or health examination clinic participated in the validation study. DFQ55 was developed from DFQ112 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. To develop a short DFQs for classifying subjects with low or high sodium intakes, the weighed score according to the sodium content of one protion size was given to each dish item of DFQ25 or DFQ14 and multiplied with the consumption frequency score. A sum index of all the dish items was formed and called sodium index (Na index). For validation study the DFQ112, 2-day diet record and one 24-hour urine collection were analyzed to estimate sodium intakes. The sodium intakes estimated with DFQ112 and 24-h urine analysis showed 65% agreement to be classified into the same quartile and showed significant correlation (r = 0.563 p < 0.05). However, the actual amount of sodium intake estimated with DFQ112 (male: 6221.9 mg, female: 6127.6 mg) showed substantial difference with that of 24-h urine analysis (male: 4556.9 mg, female: 5107.4 mg). The sodium intake estimated with DFQ55 (male: 4848.5 mg, female: 4884.3 mg) showed small difference from that estimated with 24-h urine analysis, higher proportion to be classfied into the same quartile and higher correlation with the sodium intakes estimated with 24-h urine analysis and systolic blood pressure. It seems DFQ55 can be used as a tool for quantitative estimation of sodium intake. Na index25 or Na index14 showed 39~50% agreement to be classified into the same quartile, substantial correlations with the sodium intake estimated with DFQ55 and significant correlations with the sodium intake estimated with 24-h urine analysis. When point 119 for Na index25 was used as a criterion of low sodium intake, sensitivity, specificity and positive predictive value was 62.5%, 81.8% and 53.2%, respectively. When point 102 for Na index14 was used as a criterion of high sodium intake, sensitivity, specificity and positive predictive value were 73.8%, 84.0%, 62.0%, respectively. It seems the short DFQs using Na index14 or Na index25 are simple, easy and proper instruments to classify the low or high sodium intake group.