BACKGROUND: A self-administered questionnaire on dietary habits used in the JACC Study contained a 40-item food frequency questionnaire (FFQ). Although more than 110 thousand subjects enrolled in JACC Study and responded to the FFQ, no validation study has been conducted to date. METHODS: Eighty-five volunteers among the cohort members completed 2 FFQs (FFQs 1&2) and 12-day weighed dietary records (WDR). The interval between the two FFQs was one year. During the one year, the subjects carried out a 3-consecutive-day WDR in each season. We tested the reproducibility by using two FFQs. Also, we tested the validity of the FFQ by using the 12-day WDR as a gold standard. RESULTS: The intake frequencies of the 2 FFQs often agreed, showing the Spearman correlation coefficients ranging from 0.42 (edible wild plants) to 0.86 (coffee). The Spearman correlation coefficients of the energy and nutrient intakes from FFQ2, and that of the 12-day WDR were 0.20(energy) to 0.46 (animal protein, potassium). After adjusting the energy intake, the correlation coefficients showed 0.21(fish fat) to 0.51(animal fat). When classifying the FFQ2 and WDR by quartiles and examining the degree of agreement between the two methods, we obtained its median 30%. CONCLUSIONS: The FFQ is suitable to deal with a large group of subjects. However, since the energy and the amount of nutrient intake from this FFQ can not show the overall dietary intake situation, the subjects’ dietary intake should be assessed by categories.

Background: A self-administered quantitative food frequency questionnaire (ax) was developed for a population-based cohort study on cancer in Takayama, Japan.Methods: The ax was tested among 58 male and 59 female volunteers. Average daily nutrient intakes for the previous year calculated from the ax were compared with those from 3-day food records and four 24-h recalls. The ax was also validated among 37 volunteers by comparing the nutrient intakes calculated from the ax with 12 1-day food records during a year. We also calculated the intra-class correlation coefficients for various nutrients between the ax and the second ax administered by the same volunteers 1 year after the first survey.Results: Pearson correlation coefficients between total energy from the ax and 3-day records were 0.38 for men and 0.25 for women and those between the ax and 24-h recalls were 0.19 and -0.02 for men and women, respectively. Correlations between the several nutrients from the ax and 3-day records ranged from 0.2 to 0.5 for both men and women. These correlations after energy adjustment ranged from 0.2 to 0.6 for men and from 0.1 to 0.7 for women. In general, the correlations for various nutrients between the ax and 12 1-day records were higher than those described above. The intra-class correlation coefficients ranged from 0.46 to 0.78 in men and from 0.36 to 0.67, except for vitamin C in women. When the information on portion size was excluded, almost all of the above indices showed somewhat lower figures.Conclusion: These results suggest that our food frequency questionnaire with portion size information can be used to estimate nutrient intakes of each individual.

The relationship between soy product intake and serum total cholesterol concentration was examined in 1242 men and 3596 women who participated in an annual health check-up program in Takayama City, Japan, provided by the municipality in 1992. The intake of soy products and various foods and nutrients was assessed by a semiquantitative food-frequency questionnaire. Blood samples were collected from fasting subjects to measure the serum total cholesterol concentration. A significant trend (P for trend = 0. 0001) was observed for decreasing total cholesterol concentration with an increasing intake of soy products in men after controlling for age, smoking status and intake of total energy, total protein and total fat. This negative trend (P for trend = 0.0001) was also noted in women after controlling for age, menopausal status, body mass index and intake of total energy and vitamin C. An additional adjustment for physical activity, coffee and tea consumption, and intake of cholesterol, carbohydrates, fiber and vitamin E did not change the results. These data suggest a role for soy products in human cholesterol homeostasis.

We examined the cross-sectional relationship of soy product intake to serum concentrations of estradiol (E2) and sex hormone-binding globulin (SHBG) in 50 healthy premenopausal Japanese women. Intakes of soy products and various nutrients were estimated through a semiquantitative food-frequency questionnaire. Blood samples were drawn from each subject on Days 11 and 22 of her menstrual cycle. The intake of soy products was inversely correlated with E2 on Days 11 and 22 of the cycle after controlling for age, body mass index, cycle length, and intakes of total energy, fat, and crude fiber (r = -0.23, p = 0.08 and r = -0.32, p = 0.04, respectively). No significant correlation was observed between soy product intake and SHBG. There was a tendency for the intake of individual soy foods such as tofu and miso to be inversely correlated with E2 on Days 11 and 22 of the menstrual cycle. Miso intake was inversely significantly correlated with SHBG on Day 22 of the cycle (r = -0.36, p = 0.02). If the observed association is causal, our results suggest that the consumption of soy products lowers the risk of developing breast cancer risk modifying estrogen metabolism.

Simplified methods to estimate long term nutrient intakes would be needed for not only nutritional epidemiologic studies but also other ones.Based on data of diet history questionnaires (DHQ) which ask frequency and portion size for 169 items from 2,371 participants randomly selected from our cohort study in a rural city of Japan, we simplified the DHQ by eliminating some items using stepwise regression method. To examine the validity of the simplified DHQ (SDHQ), we obtained the SDHQs from 31 volunteers who had finished to complete one-day records once a month during the previous year, we calculated Pearson's correlation coefficient and calorie-adjusted correlation coefficient between the SDHQ and twelve one-day records for each nutrient intake value. Thirty one items were selected for our SDHQ. The mean values of most nutrient intakes from the SDHQ were more than those from twelve one-day records. The correlation coefficients between the SDHQ and twelve one-day records were more than 0.30 except for fat and monounsaturated fat. Calorie adjustment increased in the correlation coefficients for some nutrients. Our results suggest that the SDHQ is a validated and easy-to-use method for assessing long term 17 selected nutrient intakes.J Epidemiol, 1997; 7 : 33-41.diet history questionnaire, one-day records, stepwise regression, validationEpidemiologic studies have indicated relationships between nutrient or food intakes and chronic diseases. Not only nutritional epidemiologic studies but also other ones should include some validated nutrient or food intake assessment methods in their researches. Hankin et al 1). developed the diet History Questionnaire (DHQ). It has been modified and used to estimate average food intakes of the residents in a rural city of Japan). However, the DHQ asked average frequency and quantity in the previous year for 169 foods and dishes and it took about one hour to complete it. Such a long questionnaire might not be suitable in epidemiologic studies where major interests are not in nutrition. We developed a shorter version of the DHQ, i.e., the simplified Diet History Questionnaire (SDHQ) to estimate 17 selected nutrient intakes. This study aims to know the validity of the SDHQ by comparing with mean estimated nutrient intake values from twelve one-day records. MATERIALS AND METHODS Development of the SDHQIn September 1992, we distributed the DHQs to all residents aged 35 years old and over in a rural city of Gifu prefecture, Japan, at the beginning of our cohort study. We received the DHQs from 34,018 among 36,990 residents (response rate: 92%). We randomly selected 2,371 subjects from 23,708 respondents who met our conditions and aged under 64 years old, and utilized the DHQ data from these subjects (They were 1,137 males including 58 subjects who had missing values in body mass index (BMI) (with mean age = 49.6 years; SD = 8.4, mean BMI = 22.8 kg/m2; SD = 2.8) and 1,234 females including 35 subjects who had missing values in BMI (with mean age = 49.3 years; SD = 8.3, mean BMI = 22.1 kg...