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Background/Objectives:The aim of this paper was to compare methods to estimate usual intake distributions of nutrients and foods. As 'true' usual intake distributions are not known in practice, the comparison was carried out through a simulation study, as well as empirically, by application to data from the European Food Consumption Validation (EFCOVAL) Study in which two 24-h dietary recalls (24-HDRs) and food frequency data were collected. The methods being compared were the Iowa State University Method (ISU), National Cancer Institute Method (NCI), Multiple Source Method (MSM) and Statistical Program for Age-adjusted Dietary Assessment (SPADE).Subjects/Methods:Simulation data were constructed with varying numbers of subjects (n), different values for the Box-Cox transformation parameter (λBC) and different values for the ratio of the within- and between-person variance (rvar). All data were analyzed with the four different methods and the estimated usual mean intake and selected percentiles were obtained. Moreover, the 2-day within-person mean was estimated as an additional 'method'. These five methods were compared in terms of the mean bias, which was calculated as the mean of the differences between the estimated value and the known true value. The application of data from the EFCOVAL Project included calculations of nutrients (that is, protein, potassium, protein density) and foods (that is, vegetables, fruit and fish).Results:Overall, the mean bias of the ISU, NCI, MSM and SPADE Methods was small. However, for all methods, the mean bias and the variation of the bias increased with smaller sample size, higher variance ratios and with more pronounced departures from normality. Serious mean bias (especially in the 95th percentile) was seen using the NCI Method when rvar=9, λBC=0 and n=1000. The ISU Method and MSM showed a somewhat higher s.d. of the bias compared with NCI and SPADE Methods, indicating a larger method uncertainty. Furthermore, whereas the ISU, NCI and SPADE Methods produced unimodal density functions by definition, MSM produced distributions with 'peaks', when sample size was small, because of the fact that the population's usual intake distribution was based on estimated individual usual intakes. The application to the EFCOVAL data showed that all estimates of the percentiles and mean were within 5% of each other for the three nutrients analyzed. For vegetables, fruit and fish, the differences were larger than that for nutrients, but overall the sample mean was estimated reasonably.Conclusions:The four methods that were compared seem to provide good estimates of the usual intake distribution of nutrients. Nevertheless, care needs to be taken when a nutrient has a high within-person variation or has a highly skewed distribution, and when the sample size is small. As the methods offer different features, practical reasons may exist to prefer one method over the other. [ABSTRACT FROM AUTHOR]

Background/objectives: We studied the ecologic relationships of food groups, macronutrients, eating patterns, and an a priori food pattern score (Mediterranean Adequacy Index: MAI) with long-term CHD mortality rates in the Seven Countries Study.Subjects/methods: Sixteen cohorts (12,763 men aged 40-59 years) were enrolled in the 1960s in seven countries (US, Finland, The Netherlands, Italy, Greece, former Yugoslavia: Croatia/Serbia, Japan). Dietary surveys were carried out at baseline and only in a subsample of each cohort. The average food consumption of each cohort was chemically analyzed for individual fatty acids and carbohydrates.Results: Ecologic correlations of diet were computed across cohorts for 50-year CHD mortality rates; 97% of men had died in cohorts with 50-year follow-up. CHD death rates ranged 6.7-fold among cohorts. At baseline, hard fat was greatest in northern Europe, olive oil in Greece, meat in the US, sweet products in northern Europe and the US, and fish in Japan. The MAI was high in Mediterranean and Japanese cohorts. The 50-year CHD mortality rates of the cohorts were closely positively ecologically correlated (r = 0.68-0.92) with average consumption of hard fat, sweet products, animal foods, saturated fat, and sucrose, but not with naturally occurring sugars. Vegetable foods, starch, and the a priori pattern MAI were inversely correlated (r = -0.59 to -0.91) with CHD mortality rates.Conclusions: Long-term CHD mortality rates had statistically significant ecologic correlations with several aspects of diet consumed in the 1960s, the traditional Mediterranean and Japanese patterns being rich in vegetable foods, and low in sweet products and animal foods. [ABSTRACT FROM AUTHOR]

Background/objectives: Evidence regarding the consumption of soy foods and isoflavones in relation to risk of type 2 diabetes (T2D) is scarce. Our study was to evaluate the association between soy food and isoflavone consumption and risk of T2D in US men and women.Subjects/methods: We followed 63 115 women in the Nurses' Health Study (1998-2012), 79 061 women in the Nurses' Health Study II (1999-2013) and 21 281 men in the Health Professionals Follow-Up Study (2002-2010). Diet was assessed by a validated food-frequency questionnaire and was updated every 4 years. Self-reports of incident T2D were confirmed by a validated supplementary questionnaire.Results: During 1 966 321 person-years of follow-up, 9185 incident T2D cases were documented. After multivariate adjustment for covariates, consumption of soy foods (tofu and soy milk) was not associated with a lower T2D risk. Compared with non-consumers of soy foods, the hazard ratio (HR) was 1.00 (95% confidence interval (CI): 0.93, 1.07) for <1 serving/week and 0.93 (95% CI: 0.83, 1.03) for ⩾1 serving/week of soy foods (P for trend=0.14). In contrast, intake of total isoflavones was inversely associated with T2D risk. Comparing extreme quintiles of isoflavones, the HR was 0.89 (95% CI: 0.83, 0.96; P for trend=0.009). Inverse associations were also found for consumption of major individual isoflavones, including daidzein and genistein, with risk of T2D.Conclusions: Intake of isoflavones was associated with a modestly lower T2D risk in US men and women who typically consumed low-to-moderate amounts of soy foods. These findings warrant replications in other populations with similar soy intake levels. [ABSTRACT FROM AUTHOR]

This study compared nutrient intakes from 7-day menus for the US MyPlate and DASH Eating Plan versus the cutoff points for green lights defined by the UK's multiple traffic light (MTL) scheme. For both diets, the foods achieved green lights for saturated fat and salt, and for beverages for total fat, saturated fat and salt. The other nutrients achieved amber lights but were within the range of the two diets. By contrast, the MTL threshold for salt in beverages was outside the range of the diets. The values for salt in beverages in the MyPlate and Dash diet plans were 0.06±0.07 and 0.19±0.01 (s.d.) g/100 ml, which are both considerably lower compared with the cutoff of 0.3 g/100 ml for an MTL green light. Adjusting the green MTL threshold values to the median values for a healthful diet could help make MTL labelling a more valid way of helping consumers choose a healthful diet. [ABSTRACT FROM AUTHOR]