Between- and within-subject variation in nutrient intake from infancy to old age: estimating the number of days required to rank dietary intakes with desired precision

Number of 24-hour diet recalls needed to estimate energy intake

PURPOSE

Twenty-four-hour diet recall interviews (24HRs) are used to assess diet and to validate other diet assessment instruments. Therefore it is important to know how many 24HRs are required to describe an individual's intake.

METHOD

Seventy-nine middle-aged white women completed seven 24HRs over a 14-day period, during which energy expenditure (EE) was determined by the doubly labeled water method (DLW). Mean daily intakes were compared to DLW-derived EE using paired t tests. Linear mixed models were used to evaluate the effect of call sequence and day of the week on 24HR-derived energy intake while adjusting for education, relative body weight, social desirability, and an interaction between call sequence and social desirability.

RESULTS

Mean EE from DLW was 2115 kcal/day. Adjusted 24HR-derived energy intake was lowest at call 1 (1501 kcal/day); significantly higher energy intake was observed at calls 2 and 3 (2246 and 2315 kcal/day, respectively). Energy intake on Friday was significantly lower than on Sunday. Averaging energy intake from the first two calls better approximated true energy expenditure than did the first call, and averaging the first three calls further improved the estimate (p=0.02 for both comparisons). Additional calls did not improve estimation.

CONCLUSIONS

Energy intake is underreported on the first 24HR. Three 24HRs appear optimal for estimating energy intake.

Effects of dietary assessment methods on assessing risk of nutrient intake adequacy at the population level: from theory to practice

The present study evaluated how applying different dietary methods affects risk assessment of inadequate intakes at the population level. A pooled analysis was conducted using data from two Spanish regional representative surveys both applying similar methodology with a total sample of 2615 individuals aged 12-80. Diet was assessed in the entire sample applying data from one 24 h recall (24HR), a mean of two non-consecutive 24HR, both crude and adjusted for intraindividual variability, and a FFQ. Intakes of vitamins A, C, E, thiamin, riboflavin, niacin, vitamin B6, vitamin B12, Fe, Mg, P and Zn were compared to the average nutrient requirement (ANR or estimated average requirement) in the entire sample and also excluding under-reporters applying the ANR cut-point method (and the probability approach for Fe). Higher percentages of intakes below the ANR were seen for 1-24HR and the mean of 2-24HR, except for nutrients with the highest rates of inadequacy (vitamins A, E, folate and Mg). For these micronutrients, higher percentages of inadequacy were obtained by adjusted 24HR data and the lowest with FFQ. For the remaining nutrients, adjusted data gave the lowest inadequacy percentages. The best concordance was seen between 2-24HR and 1-24HR as well as for adjusted 24HR, with the least observed between FFQ and the other methods. Exclusion of under-reporters considerably reduced inadequacy in both daily methods and FFQ. Crude daily data gave higher estimates of inadequate intakes than adjusted data or FFQ. Reproducibility of daily methods was also reasonably good. Results may differ depending on the micronutrient thus impeding reaching conclusions/recommendations common for all micronutrients.

Assessing individual dietary intake from common-plate meals: a new tool for an enduring practice

Objective

The purposes of the present study were to estimate individual intake from common-plate meals among Bedouin Arabs using a modified 24 h recall questionnaire, and to evaluate reported energy intake (EI) by comparison with estimated energy requirement (EER).

Design

Weighed records were used to develop a method of quantifying intake from common plates. Reported EI and nutrient intakes were obtained from administration of the modified 24 h recall. The relative standard error (RSE) was used to evaluate the reliability of reported nutrient intakes. The FAO/WHO/United Nations University and Oxford equations and reported physical activity levels were used to compute ratios of reported EI to BMR and EER.

Setting

Population centres of traditionally semi-nomadic Bedouin Arabs undergoing sedentarization/urbanization in southern Israel.

Subjects

A convenience sample of 451 adults (aged 19–82 years).

Results

Mean (se) energy intake was 9648 (276) kJ/d (2306 (66) kcal/d) for men and 8230 (172) kJ/d (1967 (41) kcal/d) for women, of which carbohydrates accounted for 63–64 %. The nutrient intakes evaluated had RSE ratios of less than 25 %. EI:EER ratios ranged from 0·86 to 0·89, and from 0·87 to 0·93 among non-dieters who ate the usual amount on the recall day.

Conclusions

The modified 24 h recall produced plausible estimates of energy and nutrient intakes, comparable to those obtained with the 24 h recall in other populations. The modified questionnaire makes an important contribution to facilitating large-scale nutritional surveillance in the Bedouin population, and may serve as a model for modifying dietary instruments to quantify individual intake in other populations that practise common-plate eating.

Urinary sugars biomarker relates better to extrinsic than to intrinsic sugars intake in a metabolic study with volunteers consuming their normal diet

BACKGROUND/OBJECTIVES

Sugars in diet are very difficult to measure because of the unreliability of self-reported dietary intake. Sucrose and fructose excreted in urine have been recently suggested as a biomarker for total sugars intake. To further characterize the use of this biomarker, we investigated whether urinary sugars correlated better to extrinsic compared to intrinsic sugars in the diet.

SUBJECTS/METHODS

Seven male and six female healthy participants were living for 30 days in a metabolic suite under strictly controlled conditions consuming their usual diet as assessed beforehand from four consecutive 7-day food diaries kept at home. During the 30-day study, all 24 h urine specimens were collected, validated for their completeness and analysed for sucrose and fructose.

RESULTS

The mean total sugars intake in the group was 202+/-69 g day(-1). Daily intake of extrinsic, intrinsic and milk sugars contributed 60.1, 34.4 and 5.5%, to the total sugars intake, respectively. The individuals' 30-day mean sugars excretion levels were significantly correlated with the 30-day means of extrinsic sugars (r=0.84; P<0.001) but not with the intrinsic sugars intake (r=0.43; P=0.144). In the regression, only extrinsic sugars intake explained a significant proportion of the variability in sugars excretion (adjusted R(2)=0.64; P=0.001); daily excretion of 100 mg sucrose and fructose in urine predicted 124 g of extrinsic total sugars in the diet. Using fewer urinary and dietary measurements in the analysis did not change the overall trend of the findings.

CONCLUSIONS

In this group of volunteers, sucrose and fructose in urine better correlated to extrinsic than to intrinsic sugars intake.

Relative validity of a semiquantitative food frequency questionnaire designed for schoolchildren in western Greece

Background

The use of food frequency questionnaires (FFQs) has become increasingly important in epidemiologic studies. During the past few decades, a wide variety of nutritional studies have used the semiquantitative FFQ as a tool for assessing and evaluating dietary intake. One of the main concerns in a dietary analysis is the validity of the collected dietary data.

Methods

This paper discusses several methodological and statistical issues related to the validation of a semiquantitative FFQ. This questionnaire was used to assess the nutritional habits of schoolchildren in western Greece. For validation purposes, we selected 200 schoolchildren and contacted their respective parents. We evaluated the relative validity of 400 FFQs (200 children's FFQs and 200 parents' FFQs).

Results

The correlations between the children's and the parents' questionnaire responses showed that the questionnaire we designed was appropriate for fulfilling the purposes of our study and in ranking subjects according to food group intake.

Conclusion

Our study shows that the semiquantitative FFQ provides a reasonably reliable measure of dietary intake and corroborates the relative validity of our questionnaire.

Ethnic variance in iron status: is it related to dietary intake?

OBJECTIVE

In New Zealand (NZ), Fe deficiency (ID) is present in 14% of children aged <2 years. Prevalence varies with ethnicity (NZ European 7%, Pacific 17%, Maori 20%). We describe dietary Fe intake, how this varies with ethnicity and whether intake predicts Fe status.

DESIGN

A random sample of children aged 6-23 months. Usual Fe intake and dietary sources were estimated from 2 d weighed food records. Associations were determined between adequacy of Fe intake, as measured by the Estimated Average Requirement (EAR), and ID.

SUBJECTS

Sampling was stratified by ethnicity. Dietary and blood analysis data were available for 247 children.

RESULTS

The median daily Fe intake was 8.3 mg (age 6-11 months) and 6.3 mg (age 12-23 months). Breast milk and milk formulas (median 58%; age 6-11 months), and cereals (41%) and fruit and vegetables (17%; age 12-23 months), were the predominant dietary sources of Fe. Fe intake was below the EAR for 25% of the children. Not meeting the EAR increased the risk of ID for children aged 6-11 months (relative risk = 18.45, 95% CI 3.24, 100.00) and 12-23 months (relative risk = 4.95, 95% CI 1.59, 15.41). In comparison with NZ European, Pacific children had a greater daily Fe intake (P = 0.04) and obtained a larger proportion of Fe from meat and meat dishes (P = 0.02).

CONCLUSIONS

A significant proportion of young NZ children have inadequate dietary Fe intake. This inadequate intake increases the risk of ID. Ethnic differences in Fe intake do not explain the increased risk of ID for Pacific children.

Corrective responses in human food intake identified from an analysis of 7-d food-intake records

BACKGROUND

We tested the hypothesis that ad libitum food intake shows corrective responses over periods of 1-5 d.

DESIGN

This was a prospective study of food intake in women.

METHODS

Two methods, a weighed food intake and a measured food intake, were used to determine daily nutrient intake during 2 wk in 20 women. Energy expenditure with the use of doubly labeled water was done contemporaneously with the weighed food-intake record. The daily deviations in macronutrient and energy intake from the average 7-d values were compared with the deviations observed 1, 2, 3, 4, and 5 d later to estimate the corrective responses.

RESULTS

Both methods of recording food intake gave similar patterns of macronutrient and total energy intakes and for deviations from average intakes. The intraindividual CVs for energy intake ranged from +/-12% to +/-47% with an average of +/-25%. Reported energy intake was 85.5-95.0% of total energy expenditure determined by doubly labeled water. Significant corrective responses were observed in food intakes with a 3- to 4-d lag that disappeared when data were randomized within each subject.

CONCLUSIONS

Human beings show corrective responses to deviations from average energy and macronutrient intakes with a lag time of 3-4 d, but not 1-2 d. This suggests that short-term studies may fail to recognize important signals of food-intake regulation that operate over several days. These corrective responses probably play a crucial role in bringing about weight stability.

Within- and between-person variations as determinant factors to calculate the number of observations to estimate usual dietary intake of adolescents

This cross-sectional study describes the variation in the dietary intake of energy and macronutrients based on estimated coefficients of within- and between-person variation and intends to calculate the number of days required to evaluate the dietary intake of adolescents in Piracicaba, Brazil. The sample was made up by ninety-two adolescents aged between eleven and sixteen years. Interviews were performed to assess demographic, anthropometric and dietary variables, which were evaluated by the answers obtained through two 24-hour recalls. Descriptive analyses were performed and variances and Coefficients of variation within- and between-person were obtained by results of one-way ANOVA. The mean energy intake observed was 2,326.2 kilocalories; mean macronutrient intake came to 89.0 grams of fatty acids, 305.3 grams of carbohydrates and 82.2 grams of proteins. Coefficients of within-person variation ranged from 36% to 45%, while between-person coefficients varied from 26% to 31%. Variance ratios ranged from 1.35 (carbohydrate) to 2.62 (protein). The lowest number of observations required to correctly evaluate the usual diet calculated (r = 0.90) was six days, for carbohydrates while the highest was eleven, for proteins. Coefficients of variation were similar to those observed in international studies. We conclude that, in this study, two observations were sufficient to obtain reasonable correlations. However, six evaluations are necessary for these adolescents in order to obtain excellent correlations.

Urinary sucrose and fructose as biomarkers of sugar consumption: comparison of normal weight and obese volunteers

Using urinary sugars as a biomarker of consumption, we have previously shown that obese people consume significantly more sugars than individuals of normal weight. However, there is concern that recovery of this biomarker may differ between normal weight and obese individuals. A total of 19 subjects, divided into two groups according to their body mass index (BMI) (normal weight BMI < or = 25 kg/m(2), n=10; obese BMI > or = 30 kg/m(2), n=9), participated in a randomized crossover dietary intervention study of three diets providing 13, 30 and 50% of energy from sugars for 4 days each while living in a volunteer suite. The mean urinary sucrose and fructose excretions in 24-h urine increased with increasing sugar consumption over the three dietary periods in both BMI groups and were significantly different between the diets (P < 0.01). There was no significant interaction effect of BMI class on the mean urinary excretions of these sugars with different sugar intakes, either as absolute values or expressed as a percentage of total sugar intake. In conclusion, BMI does not affect the validity of sucrose and fructose excretions in 24-h urine collections used as biomarkers to estimate total sugar consumption.

Sucrose in the diet of 3-year-old Finnish children: sources, determinants and impact on food and nutrient intake

The aim was to identify the important sources of added sucrose and determinants of high intake, and to evaluate what impact a high proportion of energy from added sucrose has on the intake of foods and nutrients. The subjects consisted of children invited to the nutrition study within the Type 1 Diabetes Prediction and Prevention birth cohort and born in 2001 (n 846). Of these, 471 returned 3 d food records at 3 years of age. The average daily intake of added sucrose was 35 (sd 17) g (11·3 % of energy intake) and that of total sucrose was 41 (sd 18) g (13·3 % of energy intake). Sucrose added by manufacturers accounted for 82 %, naturally occurring sucrose for 15 % and sucrose added by consumers for 3 % of the total sucrose. Juice drinks, yoghurt/cultured milks, and chocolate and confectionery were the main contributors to added sucrose intake. Consumption of rye bread, porridge, fresh vegetables, cooked potatoes, skimmed milk, hard cheeses, margarine and fat spread as well as intake of most nutrients decreased across the quartiles of added sucrose (P < 0·05). Being cared for at home, having a father with a vocational school degree, having at least two siblings and a milk-restricted diet increased the risk for a high-sucrose diet. The study implied that a high proportion of added sucrose in the diet had mainly an unfavourable impact on the intake of recommended foods and key nutrients in Finnish children. The rationale for the recommendation to reduce the intake of refined sugars to ensure adequate intakes of nutrients seems reasonable.

Concurrent comparison of energy intake and expenditure among adults in Butajira District, Ethiopia

Objective

To estimate and compare dietary energy intake (DEI) and total energy expenditure (TEE) among adults, using questionnaires.

Design

Comparative, cross-sectional study.

Setting

Community-based, at the demographic surveillance site (DSS) in Butajira District of Ethiopia.

Subjects

A total of 619 adults, 18–64 years of age, were randomly selected from among the urban and rural population of Butajira using the DSS sampling frame. Habitual dietary intake and physical activity were assessed using questionnaires. BMR was estimated using a regression equation, and TEE was calculated from BMR and the metabolic energy equivalent task (MET) and duration of reported activities. Physical activity level (PAL) was calculated as TEE/BMR, while food intake level (FIL) was calculated as DEI/BMR. The mean DEI:TEE ratio was used to evaluate reported DEI at the population level, while individual misreporters were identified by applying the Goldberg cut-off points at three levels of PAL.

Results

Based on the Goldberg method, 57 % of the study participants were identified as acceptable reporters of DEI, among whom mean TEE was 8·21 (95 % CI 8·01, 8·42) MJ (1963 (95 % CI 1914, 2012) kcal), mean DEI was 8·13 (95 % CI 7·93, 8·34) MJ (1944 (95 % CI 1895, 1993) kcal) and mean DEI:TEE was 1·01 (95 % CI 0·99, 1·04).

Conclusion

The dietary history and physical activity questionnaires provide comparable estimates of mean energy intake and expenditure at a population level. Acceptable reporters have to be identified in order to obtain better estimates. Questionnaire-based estimates of energy intake should not be interpreted without an inherent system of comparison or validation.

Variation in energy and nutrient intakes among pre-school children: implications for study design

BACKGROUND

Within- and between-person variation in nutrient intakes has been characterized in adult populations, but little is known about variation in the diet of pre-school-aged children. The aim of this study was to describe dietary variations in Flemish pre-schoolers and to estimate the number of record days required for studying diet-disease associations among pre-school-aged children.

METHODS

Data from 3-day estimated diet records, collected in 2002-03, were used from 661 pre-school children (2.5-6.5 years) in Flanders, using parents/caregivers as a proxy. Age categories for studying differences in dietary variations between age groups were based on the age groups of the Belgian dietary recommendations (2.5-3 years and 4-6.5 years).

RESULTS

Overall, micronutrient intakes had smaller variance ratios than macronutrients. The largest variance ratios were found for cholesterol followed by fat, fatty acids and sodium intakes and would result in attenuated linear regression estimates of diet-disease associations in children. Within/between variance ratios were > or =1 for most nutrients in the oldest group (4-6.5 years) of pre-school children, while <1 for most micronutrients in the youngest age group (2.5-3 years), resulting in fewer days required for this youngest age group in comparison with the oldest group. No consistent differences in variance components were found between genders. Overall, 7-day dietary records were sufficient for accurately estimating 15 of the 23 nutrients in both age groups.

CONCLUSION

The number of record days required for reliably classifying pre-school children raises with increasing age category (from 2.5-3 years to 4-6.5 years) for most nutrients and varies from 3 or 4 days for some nutrients like carbohydrates to 2 or 3 weeks for others like dietary cholesterol or monounsaturated fatty acids.

Association between dietary fat intake, liver fat, and insulin sensitivity in sedentary, abdominally obese, older men

Whether dietary fat influences the interaction between liver fat, visceral adipose tissue (VAT), and metabolic risk is unclear. Thus, we sought to determine the independent associations between 1 and 10 d dietary fat intake, liver fat, and VAT on insulin sensitivity using a cross-sectional design. Liver fat score (LFS) was assessed by computed tomography and VAT by magnetic resonance imaging in 42 abdominally obese older men. Insulin sensitivity was measured by the hyperinsulinemic–euglycemic clamp technique. Diet composition was determined from self-recorded diet records for 1 and 10 d preceding the assessment of LFS. LFS was positively associated with the 10 d average fat and alcohol intake, but not with any 1 d average dietary variables. VAT (r = –0.36) and LFS (r = –0.32) were both negatively correlated with insulin sensitivity (p < 0.05). When LFS and VAT were entered in the same model, only VAT was an independent predictor of insulin sensitivity (p < 0.05). Control for the average 10 d alcohol consumption and fat intake improved the association between insulin sensitivity and LFS (from r = –0.32, p > 0.10 to r = –0.49, p < 0.05), but not VAT. In fact, after control for the 10 d dietary variables, both LFS and VAT were independent predictors of insulin sensitivity (p < 0.05). This was not true for any of the 1 d dietary intake variables. In conclusion, liver fat is associated with dietary fat intake and alcohol consumption over 10 d, but not 1 d. Furthermore, dietary habits may influence the relationship between liver fat and insulin sensitivity.

Technology-Assisted Dietary Assessment

Dietary intake provides valuable insights for mounting intervention programs for prevention of disease. With growing concern for adolescent obesity, the need to accurately measure diet becomes imperative. Assessment among adolescents is problematic as this group has irregular eating patterns and have less enthusiasm for recording food intake. Preliminary studies among adolescents suggest that innovative use of technology may improve the accuracy of diet information from young people. In this paper, we propose a novel food record method using a mobile device that will provide an accurate account of daily food and nutrient intake among adolescents. Our approach includes the use of image analysis tools for identification and quantification of food consumption. Images obtained before and after food is consumed can be used to estimate the diet of an individual. In this paper we describe our initial results and indicate the potential of the proposed system.

Validation of a food frequency questionnaire for assessing dietary soy isoflavone intake among midlife Chinese women in Hong Kong

Substantial evidence suggests that soy isoflavones may protect against certain chronic diseases. This study aims to assess the reproducibility and validity of a 47-item semiquantitative soy FFQ (SFFQ) designed to measure the usual intake of soy isoflavones among 145 Chinese mid-life women in Hong Kong. Reproducibility of the SFFQ was assessed by the stability of dietary intake obtained at baseline (SFFQ0) and at 13-mo follow-up (SFFQ1). Relative validity was measured by comparing data collected from SFFQ1 with those derived from 23-d, 24-h dietary recalls (DR) collected during the same 1-y validation period. Isoflavone intake was calculated using analytical values from the Chinese University of Hong Kong Soy Isoflavone Database. A total of 3,217 DR were successfully obtained. The median (interquartile range) absolute intake estimated by the SFFQ1 was 0.91 (-2.7 to 6.8) mg aglucon equivalents/d higher than the 6.3 (3.7-10.7) mg aglucon equivalents/d measured by the DR (P < 0.0057; Wilcoxon's Signed Rank test). Bland-Altman analysis further demonstrated the presence of significant proportional bias between methods among Cantonese women with above-median intake (Spearman correlation coefficient; r = 0.44; P = 0.0005). Nonetheless, the intraclass and Pearson correlation coefficients, respectively, were 0.84 and 0.72 for non-Cantonese and 0.65 and 0.50 for Cantonese, showing moderate to good levels of reproducibility and validity of the SFFQ (difference between 2 intraclass correlation coefficients, P = 0.09; difference between 2 Pearson r, P = 0.16). The unadjusted and BMI-adjusted correlations were of similar magnitude. The SFFQ is a reasonably valid instrument for assessing dietary soy isoflavone exposure in Hong Kong Chinese mid-life women.

Socio-economic, behavioural and environmental factors predicted body weights and household food insecurity scores in the Early Childhood Longitudinal Study-Kindergarten

Recent increases in obesity prevalence among children in developed countries are of policy concern. While significant positive associations between households' food insecurity status and body weights have been reported for adults, it is known from the energy physiology literature that energy requirements depend on BMR, anthropometric measures and physical activity. It is therefore important to model the bi-directional relationships between body weights and households' food insecurity scores especially for children that have evolving nutrient and energy requirements. The present paper estimated dynamic random effects models for children's body weights and BMI, and households' food insecurity scores using longitudinal data on 7635 children in the USA enrolled in 1st, 3rd and 5th grades (1999-2003) of the Early Childhood Longitudinal Study-Kindergarten. The main findings were, first, physical exercise and numbers of siblings were significantly (P < 0.05) negatively associated with body weights, while households' food insecurity score was not a significant predictor. Moreover, children's body weights were significantly lower in households with higher parental education and incomes; time spent watching television and in non-parental care were positively associated with weights. Second, models for households' food insecurity scores showed that poverty and respondents' poor emotional and physical health significantly increased food insecurity. Moreover, households with children who were taller and heavier for their ages faced significantly higher food insecurity levels. Overall, the results showed that household food insecurity was unlikely to exacerbate child obesity in the USA and it is important that children receive balanced school meals and perform higher physical activity.

Relative validation of a short food frequency questionnaire to assess calcium intake in older adults

OBJECTIVE

To develop and validate a food frequency questionnaire (FFQ) for estimating calcium intake in community-dwelling older adults using a food record as the reference method.

METHOD

A validation study involving 102 subjects (67 females) aged > or =65 years and residing independently in Adelaide, Australia, between 2002-06 was performed. Estimates of calcium intake over the last year were calculated from two versions (35 and 15 items) of the FFQ and compared with average intake from four days of non-consecutive food records (4DFR).

RESULTS

Mean calcium intake from the 4DFR was 987 mg/day (95% CI 922-1051). The 35 and 15-item questionnaires gave mean intakes of 992 mg/day (95% CI 913-1,071) and 1017 mg/day (95% CI 927-1,106) respectively. Mean difference (95% limits of agreement) between the food record and the 35 and 15-item questionnaires was 5 mg (-739-729) and 28 mg (-936-879) respectively. The 15-item questionnaire demonstrated 82% sensitivity for classifying subjects with calcium intake below the estimated average requirement (EAR, 840 mg for males 51-70 years; 1,100 mg for females >51 years and males >70 years of age) and 46% specificity for classifying subjects with intake above the EAR.

CONCLUSION

The FFQ evaluated as part of this study is one of very few that has been tested across both genders and in older adults specifically. The 15-item version has demonstrated a level of sensitivity and specificity comparable with other FFQs for evaluating calcium intake.

IMPLICATIONS

The 15-item FFQ can be confidently used for measuring group mean calcium intake in older Australians or as a screening tool to allow health professionals to identify those who are most at risk of inadequate dietary calcium intake.

Underreporting of dietary intake by body mass index in premenopausal women participating in the Healthy Women Study

Underreporting patterns by the level of obesity have not been fully assessed yet. The purpose of this study was to examine the differential underreporting patterns on cardiovascular risk factor, macronutrient, and food group intakes by the level of Body Mass Index (BMI). We analyzed cross-sectional baseline nutritional survey data from the population-based longitudinal study, the Healthy Women Study (HWS) cohort. Study subjects included 538 healthy premenopausal women participating in the HWS. Nutrient and food group intakes were assessed by the one-day 24-hour dietary recall and a semi-quantitative food frequency questionnaire, respectively. The ratio of reported energy intake (EI) to estimated basal metabolic rate (BMR) was used as a measure of relative energy reporting status and categorized into tertiles. Overweight group (BMI>/=25kg/m(2)) had a higher ratio of EI to BMR (EI/BMR) than normal weight group (BMI<25kg/m(2)). Normal weight and overweight groups showed similar patterns in cardiovascular risk factors, nutrient intake, and food group intake by the EI/BMR. Fat and saturated fat intakes as a nutrient density were positively associated with the EI/BMR. Proportion of women who reported higher consumption (>/=4 times/wk) of sugar/candy, cream and red meat groups was greater in higher tertiles of the EI/BMR in both BMI groups. Our findings suggest similar patterns of underreporting of cardiovascular risk factors, and macronutrient and food group intakes in both normal and overweight women.

Energy and nutrient intakes by pre-school children in Flanders-Belgium

The objective of this cross-sectional study was to investigate energy and nutrient intakes in pre-school children in Flanders-Belgium, using multistage clustered sampling. Diets of 661 children (338 boys; 323 girls) between 2·5 and 6·5 years old were assessed, with parentally reported 3 d estimated diet records. Usual energy and nutrient intakes were compared with national and international recommendations. Statistical modelling was used to account for within-individual variation. Mean daily energy intakes (boys, 6543 kJ; girls, 5757 kJ) approached the estimated energy requirements (EER) (boys, 6040 kJ; girls, 5798 kJ) for children < 4 years old. For children at least 4 years old, mean energy intakes (boys, 6408 kJ; girls, 5914 kJ) were below the EER of 6995 and 6740 kJ/d, respectively. Mean energy percentage (en%) derived from saturated fatty acids (SFA) (13–14 en%) was above the acceptable macronutrient distribution range (AMDR) upper level of 12 en%. Mean percentages derived from MUFA (10–11 en%) and PUFA (4–5 en%) were below the AMDR lower levels of 12 and 8 en%, respectively. For fibre, iron and vitamin D intakes, < 15 % of the children reached the recommended dietary allowances. Everybody exceeded the tolerable upper intake levels for sodium. Although diets in Belgian children were adequate in most nutrients, the implications of low iron, vitamin D and fibre intakes should be investigated. Furthermore, this affluent diet, characterised by SFA, MUFA and PUFA intakes differing from the recommendations and excessive sodium intakes, might increase the risk for CVD in later life.

Taste acuity in response to zinc supplementation in older Europeans

Taste acuity declines with age and may be dependent upon Zn status. The aim of the present double-blind, randomised controlled intervention trial has been to determine taste acuity in response to Zn supplementation (placebo, or 15 or 30 mg Zn/d). Healthy older European adults aged 70–87 years were recruited within Italy (Rome) (n 108) and France (Grenoble) (n 91) to the European Commission-funded Zenith project. A signal detection theory approach was adopted for taste assessment. The data were converted to R indices and analysed by repeated-measures ANOVA controlling for baseline taste acuity as well as serum and erythrocyte Zn. Serum Zn increased post-intervention, indicating compliance with the intervention. Results differed across geographical region. Salt taste acuity was greater in response to Zn (30 mg) than placebo post-intervention among those recruited in Grenoble. There was no apparent change in acuity for sweet, sour or bitter taste in response to Zn. Supplemented Zn may have potential to enhance salt taste acuity in those over the age of 70 years. Further research is required to determine if enhanced salt taste acuity is reflected in the eating experiences of older individuals.

Plasma n-6 and n-3 polyunsaturated fatty acids as biomarkers of their dietary intakes: a cross-sectional study within a cohort of middle-aged French men and women

OBJECTIVE

To measure the correlations between habitual intakes of individual n-6 and n-3 polyunsaturated fatty acids (PUFA) and their percentages in total plasma fatty acids in a population of adult men and women.

SUBJECTS/METHODS

Two hundred and seventy-six men and 257 women aged 45-60 (men) or 35-60 (women) at baseline, volunteers of the French SU.VI.MAX cohort. Fifteen 24-h record questionnaires were used to estimate the habitual intake of energy, total fat and linoleic, alpha-linolenic acid, arachidonic, eicosapentaenoic (EPA), n-3 docosapentaenoic (DPA) and docosahexaenoic (DHA) acids. Fatty acid composition of fasting plasma total lipids has been determined at baseline.

RESULTS

Dietary intakes of linoleic acid, arachidonic acid, EPA and DHA were weakly but significantly correlated (0.16<r<0.28, P<0.01) with their respective percentages in plasma total fatty acids in both men and women. No correlation was observed between the plasma levels of alpha-linolenic acid and its dietary intake, and between the plasma levels of arachidonic acid and long-chain n-3 PUFA and the intakes of their 18-carbon precursors, linoleic and alpha-linolenic acid, respectively.

CONCLUSIONS

The percentages of linoleic acid, arachidonic acid, EPA and DHA in plasma total fatty acids, but not that of alpha-linolenic acid, are acceptable markers of their habitual levels of intake. The plasma levels of long-chain n-6 and n-3 PUFA are not influenced by the intake levels of their precursors, linoleic and alpha-linolenic acids.

Twenty-four-hour urinary thiamine as a biomarker for the assessment of thiamine intake

OBJECTIVE

To investigate 24-h urinary thiamine as a potential biomarker for thiamine intake for use in validation studies to assess the validity of dietary intake data collected by self-reporting dietary methods.

SUBJECTS

Seven male and six female healthy participants living for 30 days in a metabolic suite under strictly controlled conditions consuming their usual diet as assessed beforehand from four consecutive 7-day food diaries kept at home. During the 30-day study, all 24-h urine specimens were collected, validated for their completeness and analysed for thiamine.

RESULTS

Thirty-day mean (+/-s.d.) calculated thiamine intake was 2.22+/-0.55 mg/day. Thirty-day mean (+/-s.d.) urinary excretion of thiamine was 526.5+/-193.0 microg/day (24.7+/-8.10% of intake). There was a highly significant correlation between individuals' 30-day means of thiamine intake and their mean excretion level (r=0.720; P=0.006), where 1 mg of thiamine intake predicted 268.2 microg of thiamine in urine. The correlations between intake and excretion remained significant when measurement from a single 24-h urine collection was used (r=0.56).

CONCLUSION

Twenty-four-hour urinary thiamine can be used as a concentration biomarker for thiamine intake in dietary validation studies.

Dietary zinc intake and sex differences in taste acuity in healthy young adults

BACKGROUND

Previous research suggests that adequate dietary zinc intake may be important in determining the sensory experience of food, appetite and consequently, dietary quality. The aim of this pilot study was to explore relationships between taste sensitivity and dietary zinc intake in healthy young adults (age 20-40 years: 24 male, mean age +/- SD = 27 +/- 4.86 years; 26 female, mean age +/- SD = 23 +/- 2.10).

METHOD

A signal detection method was used to assess taste acuity for the four basic tastes: sweet (glucose), sour (citric acid), salt (sodium chloride) and bitter (quinine). A 4-day food diary was used to determine dietary intakes of zinc (mg day(-1)) and salt.

RESULTS

Males reported a higher zinc intake than females (P=0.001). Higher dietary zinc intake was associated with better taste acuity for salt in females (P=0.017) but not in males. Acuity for bitter taste appeared to be related to zinc intake in males (P=0.007) but not females. Among those whose average daily zinc intake was below the RNI, males were less sensitive than females to sour (P=0.02) and bitter (P=0.014) taste.

CONCLUSION

These findings suggest that zinc is more important for taste acuity in males than females and indicate the importance of taking sex differences into account when studying taste acuity.

Altering portion sizes and eating rate to attenuate gorging during a fast food meal: effects on energy intake

OBJECTIVE

Eating large amounts of food at a rapid rate, defined as gorging, may contribute to excess energy intake. We aimed to evaluate whether altering portion sizes and eating rate could decrease energy intake during an extra-large fast food meal.

METHODS

Subjects were adolescents (n = 18), 13 to 17 years of age, who reported eating fast food > or =1 time per week. BMI exceeded the 80th percentile for all subjects. Three feeding conditions were evaluated with a crossover design. Total amounts and types of foods and beverage served during the meal were held constant across conditions, equaling approximately 125% of that consumed during a baseline assessment visit when subjects were offered unlimited amounts. The meal (chicken nuggets, French fries, and cola) was presented as 1 large serving at a single time point (condition A, standard), portioned into 4 smaller servings presented at a single time point (condition B, effects of portioning), or portioned into 4 smaller servings presented at 15-minute intervals (condition C, effects of portioning and eating rate). Energy intake across conditions was compared by using analysis of variance.

RESULTS

Energy intake was not significantly different, whether expressed in kilojoules (mean +/- SEM: condition A, 5552 +/- 357 kJ; condition B, 5321 +/- 433 kJ; condition C, 5762 +/- 500 kJ) or relative to total daily energy expenditure (mean +/- SEM: condition A, 51.9 +/- 3.5%; condition B, 48.2 +/- 4.0%; condition C, 53.0 +/- 4.3%).

CONCLUSIONS

Adolescents consumed approximately 50% of energy needs regardless of manipulations in portion sizes and eating rate to attenuate gorging. This finding suggests that nutritional factors inherent to fast food, such as low levels of dietary fiber, high palatability, high energy density, high fat content, high glycemic load, and high content of sugar in liquid form promote excess energy intake.

Minimizing random error in dietary intakes assessed by 24-h recall, in overweight and obese adults

OBJECTIVE

To determine the minimum number of days of dietary intake interviews required to reduce the effects of random error (day-to-day variability in dietary intake) when using the multiple-pass, multiple-day, 24-h recall method.

DESIGN

Cross-sectional study.

SETTING

University research department.

SUBJECTS

A total of 50 healthy non-smoking overweight and obese (body mass index=26-40 kg/m2) adult men and women aged 39-45 years completed the study. Participants were randomly selected from volunteers for a larger unrelated study.

INTERVENTIONS

Each participant completed 10, multiple-pass, 24-h recall interviews on randomly chosen days over 4 weeks. The minimum number of record days was determined for each macronutrient (carbohydrate, fat, protein) and energy, for each gender, to obtain a 'true' (unobservable) representative intake from reported (observed) dietary intakes.

RESULTS

The greatest number of days required to obtain a 'true' representative intake was 8 days. Carbohydrate intakes required the greatest number of days of dietary record among males (7 days), whereas protein required the greatest number of days among females (8 days) in this cohort. Sunday was the day of the week that showed greatest variability in macronutrient intakes. Protein (P<0.05) and fat (P<0.001) intakes were significantly more variable than carbohydrate on Sundays compared with weekdays, for both men and women.

CONCLUSION

A logistically achievable 8 days of dietary intake interviews was sufficient to minimize the effect of random error when using the multiple-pass, 24-h recall dietary intake method. Sunday should be included among the dietary interview days to ensure a 'true' representation of macronutrient intakes. This method can be confidently applied to small cohort studies in which dietary intakes from different groups are to be compared or to investigations of associations between nutrient intakes and disease.

Issues in dietary intake assessment of children and adolescents

Studies of food habits and dietary intakes face a number of unique respondent and observer considerations at different stages from early childhood to late adolescence. Despite this, intakes have often been reported as if valid, and the interpretation of links between intake and health has been based, often erroneously, on the assumption of validity. However, validation studies of energy intake data have led to the widespread recognition that much of the dietary data on children and adolescents is prone to reporting error, mostly through under-reporting. Reporting error is influenced by body weight status and does not occur systematically across different age groups or different dietary survey techniques. It appears that the available methods for assessing the dietary intakes of children are, at best, able to provide unbiased estimates of energy intake only at the group level, while the food intake data of most adolescents are particularly prone to reporting error at both the group and the individual level. Moreover, evidence for the existence of subject-specific responding in dietary assessments challenges the assumption that repeated measurements of dietary intake will eventually obtain valid data. Only limited progress has been made in understanding the variables associated with misreporting in these age groups, the associated biases in estimating nutrient intakes and the most appropriate way to interpret unrepresentative dietary data. Until these issues are better understood, researchers should exercise considerable caution when evaluating all such data.

Validity and reproducibility of a semi-quantitative food-frequency questionnaire for estimating calcium intake in Belgian preschool children

Relative validity and reproducibility of a semi-quantitative food-frequency questionnaire (FFQ) for measuring preschool children's usual Ca intake were assessed using parents or guardians as a proxy. Estimated diet records (EDR; 3d) were used as the reference method and reproducibility was measured by repeated FFQ administrations 5 weeks apart. From 2095 preschool children (2·5–6·5 years) randomly selected in Flanders (Flemish region of Belgium), 1052 returned a FFQ and EDR. Stringent exclusion procedures reduced the sample for validity analyses to 509 children. From a separate sample of 244 preschool children, 124 returned two FFQ, of whom sixty were included in the reproducibility analysis. Mean Ca intakes were 838 (sd 305) and 777 (sd 296) mg/d for EDR and FFQ respectively, indicating a mean difference of 60·9 (sd 294·4) mg/d (p<0·001). Pearson's correlation was 0·52. Cross-classification analysis of the FFQ and EDR classified 83%of the subjects in the same or adjacent category and 2·4% in extreme quartiles. Actual values for surrogate FFQ quartiles showed a progressive increase in Ca intake (p<0·001). The FFQ correctly identified 77% of the children consuming less Ca than the age-specific RDA (800mg/d). Correlation between repeated administrations was 0·79. No significant difference between mean Ca intakes was established by two administrations (23·8 (sd 161·2) mg/d). Cross-classification of repeated administrations classified 93·4% of the subjects in the same or adjacent category and no subjects in extreme categories. This FFQ tended to underestimate preschool children's Ca intake when administered by a proxy. However, it demonstrated good repeatability and fairly good ability to classify subjects into extremes of Ca intake.

Financial incentive for diet recall accuracy does not affect reported energy intake or number of underreporters in a sample of overweight females

Underreporting of energy intake in diet recalls is common, especially among obese individuals. Incentives have been used to ameliorate the problem, but are typically provided without efficacy assessment. The present study sought to determine whether financial incentives decrease underreporting in diet recalls. Three groups were used to assess incentive timing effects in this parallel group crossover study. One group received a $50 bonus for accurate diet recalls on the first two of four recalls. Accuracy was purportedly verified by salivary analysis. Another group received the $50 bonus for the last two recalls. A third group received no incentive. Mean energy intake during the first two visits was compared to mean energy intake during the last two visits to assess differences resulting from the incentive. Underreporters were identified using a Goldberg cutoff and energy intake <76% of estimated energy expenditure. Energy intake did not differ within or between groups at any time, and the number of underreporters was not associated with group at any time. Overall, the incentive was ineffective in this small, homogeneous sample. Future studies should assess different forms of incentives, other study populations, and the probability of incentives causing undereating.

Swedish pre-school children eat too much junk food and sucrose

AIM

To analyze dietary intake in healthy 4-year-old children.

METHODS

Families from three Paediatric Health Care Centres in different socio-economic areas in Göteborg completed 7-day food records and questionnaires about socio-economy.

RESULTS

One hundred thirty two/153 completed the study, 49% of parents were university educated. Eighteen percent of children were overweight/obese. Energy intake was high; 67% had sucrose intake exceeding Nordic Nutrition Recommendations (NNR) but 36% had n-3 fatty acid intake < 0.5 energy percent. Significant negative correlations were found between sucrose and fat and between BMI and fat intake. Junk food supplied 24% of energy. Ninety-two percent had low vitamin D intake, 70% low iron and 21% low calcium intake. Gruel, which was consumed by 28%, had a positive impact on micronutrient intake. Child care and mother's origin seemed to influence dietary intake.

CONCLUSION

In 4-year olds from well-educated urban families, 18% was overweight/obese. Total energy intake was above present NNR but lower than 20 years ago, when overweight was rare. Fat energy intake was negatively associated with BMI, and low n-3 fatty acid intake was associated with higher body weight. In several aspects dietary intake was not optimal in the children.

Modest changes in dietary intake across the menstrual cycle: implications for food intake research

Food intake varies across the menstrual cycle in mammals, energy intake usually being greater in the premenstrual phase compared with the postmenstrual phase. Premenstrual increments in energy intake and a preferential selection of carbohydrate have been suggested to be greater in women with premenstrual syndrome (PMS), who may be more sensitive to cyclical hormonal or neurotransmitter fluctuations. This has direct implications for research within populations of women, especially where the primary outcome is diet or a change in energy balance. We aimed to determine whether: the premenstrual intake of energy and macronutrients differed from the postmenstrual intake; the change in intake across the menstrual cycle differed in women with PMS compared with controls; and the change in intake was related to the severity of premenstrual symptoms. We collected 3 d dietary intake data during the postmenstrual and premenstrual phases of the menstrual cycle in thirty-one women with PMS and twenty-seven control women. The consumption of energy and macronutrient intake were similar between the phases of the cycle in women with PMS. Conversely, intakes were usually greater premenstrually in control women, although not all differences were statistically significant. Exceptions were with non-milk extrinsic sugars and alcohol, which were both consumed in greater amounts in the premenstrual phase in women with PMS. Significant correlations were observed between the severity of symptoms and the change in the consumption of these nutrients. These data suggest that a consideration of the menstrual cycle phase and PMS in diet may not be warranted, especially in cross-sectional analysis, although it may need to be taken into account when examining change in intake during dietary interventions.

Validity and reliability of the Block98 food-frequency questionnaire in a sample of Canadian women

Objective

To assess the validity and reliability of the most recent adaptation of Block's full-diet food-frequency questionnaire (FFQ) among a sample of Canadian women.

Design

Participants completed a self-administered FFQ (FFQ1), two unannounced 24-hour recalls (weekday and weekend) and a second FFQ (FFQ2) between October 2003 and February 2004. FFQs and recalls were analysed for 32 nutrients using Block Dietary Data Systems and the University of Minnesota's Nutrient Data System. Mean and median intakes were computed, along with crude and deattenuated Pearson correlation coefficients between FFQ1 and the average of two recalls (validity) and between FFQ1 and FFQ2 (reliability).

Setting

Ontario, Canada.

Subjects

A random population-based sample (n = 166) of women aged 25 to 74 years.

Results

One hundred and fifteen (69%) women completed FFQ1, 96 completed FFQ1 and both recalls, and 93 completed both FFQs, about 56 days apart. Mean intakes were similar for most nutrients. FFQ reliability was high, with Pearson correlation coefficients having a median of 0.75, ranging from 0.57 to 0.90 (macronutrients) and from 0.65 to 0.88 (micronutrients from supplements and food). FFQ validity was moderate to high, with deattenuated Pearson correlation coefficients having a median of 0.59, ranging from 0.11 to 0.73 (macronutrients) and from 0.50 to 0.76 (micronutrients from supplements and food). Our micronutrient correlations were similar to or higher than those of other studies that included supplements. Two correlations <0.40 were associated with fats.

Conclusions

The validity and reliability of this full-diet version of the Block FFQ were moderate to high, supporting its use in future studies among Canadian women.

Validation of a semi-quantitative food-frequency questionnaire used among 2-year-old Norwegian children

Objectives:

An adequate diet is of profound importance in infancy and early childhood. To ensure an optimal diet, knowledge about actual intake must be obtained. The aims of this study were to assess the validity of a semi-quantitative food-frequency questionnaire (SFFQ) applied in a large nation-wide survey among 2-year-old children and to examine the validity of the SFFQ in relation to different background parameters.

Design:

The SFFQ was administered to the parents close to the child's second birthday, and one to two weeks later they started to weigh and record the child's diet for 7 days.

Subjects:

One-hundred and eighty-seven families with a 2-year-old child completed both methods.

Results:

There were no differences between the intakes of protein, saturated fatty acids, total carbohydrates and calcium estimated from the two methods. The average intake of all micronutrients, except for calcium, was overestimated by the SFFQ. Bland–Altman plots showed a systematic increase in difference between the two methods with increasing intake for most nutrients. Spearman correlation coefficients between methods for nutrient intakes ranged from 0.26 to 0.50, the median correlation was 0.38. The correlations increased when estimates were adjusted for energy intake, the median correlation being 0.52. Differences in observed validity were found according to the number of siblings.

Conclusions:

This study indicates that the SFFQ may be a valuable tool for measuring average intakes of energy, macronutrients and several food items among a 2-year-old population in Norway. The ability of the questionnaire to rank children according to intakes of nutrients and food items was rather low.

Fiber intakes and anthropometric measures are predictors of circulating hormone, triglyceride, and cholesterol concentrations in the women's health trial

The unhealthy eating patterns and obesity among women in the U.S. are indicated by changes in biomarkers, such as insulin, lipoproteins, and estradiol, that are risk factors for breast cancer and cardiovascular diseases. This article models the inter-relations among diet, serum insulin, estradiol, and sex hormone binding globulin (SHBG) concentrations, plasma LDL and HDL cholesterol, and net triglyceride concentrations, using the data at baseline and 12 mo on 379 and 615 postmenopausal women in the Control and Intervention groups, respectively, of the Women's Health Trial: Feasibility Study in Minority Populations. Subjects in the Intervention group received detailed advice over a period of 1 y for reducing fat intakes and increasing the consumption of whole grains and fruits and vegetables. The main findings were that there were significant differences between the Control and Intervention groups in the changes from baseline to 12 mo in LDL and HDL cholesterol and SHBG concentrations. Second, using a comprehensive random effects modeling framework, the ratio of fiber to energy intake was significantly associated (P < 0.05) with lower insulin and triglyceride levels, and with a higher HDL cholesterol concentration in the Intervention group. Third, the subjects' waist-to-hip ratio and BMI were significantly associated with insulin, SHBG, LDL and HDL cholesterol, and triglyceride concentrations. Fourth, insulin levels were significantly negatively associated with SHBG and HDL cholesterol, and positively associated with LDL cholesterol, triglyceride, and estradiol concentrations. Overall, weight loss, especially around the waist, and increased fiber intakes are likely to be beneficial for lipid, cholesterol, and hormone profiles of U.S. women.

Dietary intakes and food sources of fatty acids for Belgian women, focused on n-6 and n-3 polyunsaturated fatty acids

The intake of fat, saturated and monounsaturated FA (SFA and MUFA), and omega-6 and omega-3 PUFA has been estimated in 641 Belgian women (age 18-39 y). Their food intake was recorded using a 2-d food diary. The PUFA included were linoleic (LA), alpha-linolenic (LNA), arachidonic (AA), eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) acids. The mean total fat intake corresponded to 34.3% of total energy intake (E). The mean intake of the FA groups corresponded to 13.7%, 13.1%, and 6.0% of E, for SFA, MUFA, and PUFA, respectively. The mean intake of LA was 5.3% of E and of LNA was 0.6% of E, with a mean LA/LNA ratio of 8.7. The mean intake of AA was 0.03% of E. The mean intake of EPA, DPA, and DHA was 0.04%, 0.01%, and 0.06% of E, respectively. According to the Belgian recommendations, the total fat and SFA intake was too high for about three-quarters of the population. The mean LA and overall n-6 PUFA intake corresponded with the recommendation, with part of the population exceeding the upper level. Conversely, the population showed a large deficit for LNA and n-3 PUFA. The major food source for LA and LNA was fats and oils, followed by cereal products. The main sources of long-chain PUFA were fish and seafood, and meat, poultry, and eggs. From a public health perspective, it seems desirable to tackle the problem of low n-3 PUFA intake.

Community assessment of availability, consumption, and cultural acceptability of food sources of (pro)vitamin A: toward the development of a dietary intervention among preschool children in rural Burkina Faso

BACKGROUND

Vitamin A deficiency remains a public health problem in Burkina Faso and elsewhere in the developing world. Dietary diversification is a promising strategy that needs to be explored to strengthen the country's ongoing supplementation program.

OBJECTIVE

The purpose of this study was to identify locally available and acceptable (pro)vitamin A-rich foods to be included in a dietary intervention addressing vitamin A deficiency in children aged six months to three years.

METHODS

A food ethnographic study combining recall methods, observation, and focused group discussion was conducted in the dry and rainy seasons. Thirty-five mother-child pairs were randomly selected and included in the study.

RESULTS

The dietary pattern of children was characterized by low diversity with extremely low energy and vitamin A intake in both seasons. The study identified the availability of numerous (pro)vitamin A-rich foods, but these foods are either not consumed or consumed by few in low amounts and/or in low frequencies. The main constraining factors identified are related to financial accessibility (for liver), seasonal availability (for egg, milk, mango, papaya, and green leafy vegetables), and beliefs related to consumption and preparation (for green leafy vegetables). However, the study also revealed that the study population associated all identified (pro)vitamin A-rich foods with positive attributes such as health, strength, and vitamin richness, which might offer an entry point for designing and implementing dietary interventions.

CONCLUSIONS

Based on the findings of this formative research, intervention strategies with mango and liver are proposed to improve the vitamin A intake and status of children in the rural areas of Burkina Faso.

Sources of variation in nutrient intakes among men in Shanghai, China

BACKGROUND AND OBJECTIVE

Random errors, from any source, will attenuate epidemiological risk estimates. Before we launched the Shanghai Men's Health Study (SMHS), a large population-based cohort study investigating the diet-cancer association among Chinese men, a dietary calibration study was conducted among 96 men aged 40-75 years (mean age 56.5 years), with biweekly 24-hour dietary recalls (24HDRs) implemented over a 1-year period. Data from this study were analysed to evaluate the nature and magnitude of variances for intake of 26 nutrients among SMHS participants, to compare variance ratios of 26 nutrients among Chinese men and women and individuals in other studies, and to estimate the number of 24HDRs required for future dietary calibration studies in similar populations.

DESIGN

Ninety-six healthy, free-living men in Shanghai were administered biweekly 24HDR interviews 24 times over a 1-year period. To assess between-individual and within-individual contributions to variance, a mixed effects model was fitted and ratios of within-individual to between-individual (sigma(w)(2)/sigma(b)(2)) dietary intake variances were computed.

SETTING

Shanghai, China.

RESULTS

In agreement with reports from studies conducted in the USA and many other countries, we found that within-individual variances were usually larger than between-individual variances in dietary intake for all nutrients. The sum of all other variation (e.g. weekday and weekend, seasonal, interviewer) accounted for less than 5% of total variation. Ratios of within- to between-individual variances (for log-transformed data) ranged from 1.25 for carbohydrate intake to near 8 for delta-tocopherol intake.

CONCLUSIONS

The results of this study suggest that among middle-aged and elderly Chinese men in Shanghai, within- and between-individual variation account for more than 95% of the total variation for 26 nutrients. Further dietary validation studies in the same population could be adequately carried out with only 12 days of dietary recalls, if 100 participants were enrolled.

Risk factors and prevalence of periodontitis in community-dwelling elders in Mexico

AIM

The objective of this study was to determine whether an association existed between chronic systemic diseases/conditions, risk factors common in old age, and the extent and severity of chronic periodontal disease.

MATERIALS AND METHODS

Sociodemographic and lifestyle characteristics were examined by contrasting rural, urban-marginal, and urban social environments in Central Mexico. Data were analysed with Analysis of Variance, chi2 tests, and multivariable logistic regression.

RESULTS

A total of 473 adults 60 years old and over were interviewed; 315 were also examined and underwent laboratory assays (participation rate, 66%); women, 62%; mean age 73+/-8 years; 23% edentulous. The distribution of periodontitis by sociodemographic variables showed differences across locales (73% low-urban, 57% middle-urban, 29% rural). The regression model indicated that periodontitis was more frequently associated with low-urban locale, higher systolic blood pressure, higher body mass index, and worse calculus readings, with an interaction whereby being obese and having a high calculus index was associated with a high probability of having periodontitis.

CONCLUSIONS

Overall periodontal conditions were fair. While we identified oral, systemic, and social variables that modulated the experience of periodontitis, it would appear that urban, low social class elders appeared to have worse periodontal conditions.

Dietary energy intake at the age of 4 months predicts postnatal weight gain and childhood body mass index

OBJECTIVE

Rapid infant weight gain has been shown to predict later obesity risk; however, it is unclear which factors influence infant diet and weight gain. The objective of this study was to determine whether different feeding patterns and energy intakes that are provided to infants affect body weight and BMI later in childhood.

METHODS

This representative birth cohort study was conducted in the United Kingdom. Energy intake at age 4 months was estimated from 1-day unweighed dietary records in 881 infants and related to their childhood weight gain and BMI.

RESULTS

Among formula- or mixed-fed infants (N = 582), energy intake was higher in first-born infants (mean +/- SE: 2730 +/- 29.4 kJ/day; n = 263) than in subsequent-born infants (2620.8 +/- 25.2 kJ/day; n = 296). Energy intake at 4 months was also higher in infants who were given solid foods earlier (1-2 months: 2805.6 +/- 50.4 kJ/day, n = 89; 2-3 months: 2658.6 +/- 25.2 kJ/day, n = 339; 4+ months: 2587.2 +/- 46.2 kJ/day, n = 111). Higher energy intake at 4 months predicted greater weight gain between birth to age 1, 2, or 3 years and larger body weight and BMI at ages 1 to 5 years. No significant associations were seen in breastfed infants (N = 299).

CONCLUSIONS

Among formula- or mixed-fed infants, dietary energy intake at age 4 months predicted postnatal weight gain and childhood obesity risk. Both prenatal and postnatal factors may influence infant energy intake and postnatal weight gain.

Lower limb fracture, cognitive impairment and risk of subsequent malnutrition: a prospective evaluation of dietary energy and protein intake on an orthopaedic ward

OBJECTIVE

To report the dietary energy and protein intake of undernourished older adults (with and without cognitive impairment) admitted to hospital following a lower limb fracture and to determine whether dietary intakes met estimated requirements.

DESIGN

An observational study of a sequential sample.

SETTING

The orthopaedic ward of a South Australian metropolitan teaching hospital.

SUBJECTS

Sixty-eight patients aged > or =70 years screened as undernourished and admitted to hospital following lower limb fracture (50% cognitively impaired) provided 3 to 5 days of dietary data. MAJOR OUTCOME METHODS: Dietary energy and protein intake.

METHODS

Dietary assessment using plate waste methodology and snack record charts commenced within 6 days postinjury and continued for up to five consecutive days or until discharge. Estimated resting energy requirements were calculated and adjusted for activity equivalent to bed rest and physiological stress. Protein requirements were calculated as 1 g/kg/day. Cognition was assessed using the Short Portable Mental Status Questionnaire.

RESULTS

Cognitively impaired participants and those without cognitive impairment consumed, mean (95% CI) respectively, 3661 kJ/day (3201, 4121) versus 4208 kJ/day (3798, 4619) and 38 g (33, 44) versus 47 g (41, 52) protein/day. Cognitively impaired participants consumed mean (95% CI) 48% (43, 53) of estimated total energy expenditure and 78% (69, 87) of estimated protein requirements.

CONCLUSIONS

Orthopaedic fracture patients at greatest nutritional risk, including those with cognitive impairment, do not achieve estimated energy or protein requirements from diet alone. Effective methods of achieving requirements in this vulnerable group are needed before improvements in outcomes will be observed.

Effect of impact exercise on bone mineral density in elderly women with low BMD: a population-based randomized controlled 30-month intervention

Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants (n=160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [-1.1%, 95% confidence interval (CI) -0.1% to -2.1% and -1.6%, 95% CI -0.4% to -2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (-7.7%, 95% CI -9.7% to -5.6% vs. -2.9%, 95% CI -5.3 to -0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention (P=0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.

Fitness-for-purpose of dietary survey duration: a case-study with the assessment of exposure to ochratoxin A

The duration of food consumption survey may have a marked effect on estimates of usual nutrient intakes in individuals and groups. This arises from a high degree of within-person variability in food intakes, primarily on a day-to-day basis. Both the level of observation-populations versus individuals-and the desirable level of precision decide upon the 'fitness-for-purpose' of dietary survey duration. Though similar from a methodological standpoint, the question was rarely addressed in the case of non-nutrients. Our work aims at estimating the number of days of food records needed for the assessment of usual intakes of food chemicals as a function of research purpose. Focusing on the French population exposure to food mycotoxin ochratoxin A, we implement a range of well-established methods borrowed from the field of nutrient intakes assessment. Our results on OTA show that: (a) at the population level, as low as three days give satisfactory distributional estimates; yet, the implementation of variance reduction methods is of particular relevance when higher percentiles of exposure are at stake; (b) the estimation of individual usual intakes based on food records is behind practical possibilities, which calls for alternative options such as biomarkers of exposure.

Lack of Relationship between Calcium Intake and Body Size in an Obesity-Prone Population

OBJECTIVE

Dietary calcium intake, especially from dairy products, may have a protective effect against obesity. This study aimed to determine if calcium intake is associated with body weight and adiposity in Pima Indians, an obesity-prone population.

RESEARCH METHODS AND PROCEDURES

Subjects were 65 Pima Indian adults (35 men/30 women, age 33+/-8 years [mean+/-standard deviation]) participating in a study of eating behavior and 78 Pima Indian children (36 boys/42 girls, age 10.4+/-0.3 years) participating in a study of childhood obesity. Height and weight were measured, and body composition was determined by dual-energy x-ray absorptiometry. Food intake in adults was assessed using the Block 1998 Food Questionnaire; food intake in children was assessed using a 24-hour recall with parental assistance.

RESULTS

In adults, mean energy intake was 3,163+/-1,037 kcal/day, mean percentage of energy from fat was 41%+/-7%, and calcium intake was 914+/-333 mg/day. In children, mean energy intake was 1,988+/-733 kcal/day, mean percentage of energy from fat was 36%+/-9%, and calcium intake was 637+/-352 mg/day, half the recommended daily intake for this age group. There were no significant associations between calcium intake and body weight (r=0.05, P=.71; r=0.04, P=.73), body fat (r=0.16, P=.19; r=0.12, P=.42), or body mass index (r=0.01, P=.97; r=0.04, P=.77) in either adults or children, respectively.

DISCUSSION

One explanation for the lack of association between reported calcium intake and body size in Pima Indians may be that the high-fat, high-energy diet consumed by the population overwhelmed the "anti-obesigenic" effect of calcium.

CONCLUSIONS

We were unable to find an association between calcium intake and body size or adiposity in Pima Indian adults and children. Although the essentiality of calcium to bone health is well established, the role of calcium and dairy product intake in obesity and weight management remains uncertain.

Modeling the effects of health status and the educational infrastructure on the cognitive development of Tanzanian schoolchildren

This paper models the proximate determinants of school attendance and scores on cognitive and educational achievement tests and on school examinations of over 600 schoolchildren from the Control group of a randomized trial in Tanzania, where children in the Intervention group heavily infected with hookworm and schistosomiasis received treatment. The modeling approach used a random effects framework and incorporated the inter-relationships between school attendance and performance on various tests, controlling for children's health status, socioeconomic variables, grade level, and the educational infrastructure. The empirical results showed the importance of variables such as children's height and hemoglobin concentration for the scores, especially on educational achievement tests that are easy to implement in developing countries. Also, teacher experience and work assignments were significant predictors of the scores on educational achievement tests, and there was some evidence of multiplicative effects of children's heights and work assignments on the test scores. Lastly, some comparisons were made for changes in test scores of treated children in the Intervention group with the untreated children in the Control group.