The application of a handheld personal digital assistant with camera and mobile phone card (Wellnavi) to the general population in a dietary survey

This study was carried out to examine first, the validity of a new dietary assessment method, a handheld personal digital assistant with camera and mobile phone card (Wellnavi), in comparison with a weighed diet record as a reference method and second, the relation between obesity and underreporting in the Wellnavi method in 27 men and 48 women volunteers aged 30-67 y from the general population. On the validity, there were significant correlations (0.32-0.75) between the daily nutrient intakes measured by the Wellnavi method and the weighed diet record method in all the subjects except for some nutrients such as iron, magnesium and vitamin E. Results similar to those from the group of all the subjects were obtained in the men's group and the women's group. In all the subjects and the men's group and the women's group, the differences in the daily nutrient intakes between the two dietary assessment methods were statistically significant. However, good agreement of the differences between the two dietary assessment methods for many daily nutrient intakes was obtained in the nonobese men. The nutrient intakes estimated by the Wellnavi method in all the subjects and the men's group and the women's group were significantly lower than those values estimated by the weighed diet record method except for some nutrients such as sodium, iron and fat-soluble vitamins. With respect to the relation between obesity and underreporting, the obesity in women was not a factor of underreporting in the Wellnavi method, but the presence of this relation was undeniable in the obese men. The reason why the values of daily nutrient intakes in the Wellnavi method were lower than those estimated by the weighed diet record method seemed to be the low quality of the digital photo of the Wellnavi instrument. By improving the digital photo quality of this instrument, the Wellnavi method could become a useful new dietary assessment method to get accurate dietary information from people of a wide range of age and occupation, and a wide variety of physical situations of subjects from the general population.     

Development of a new instrument for evaluating individuals' dietary intakes

OBJECTIVE: With the aim of developing a new dietary instrument for assessing an individual's usual intakes, we evaluated a hand-held personal digital assistant with camera and mobile telephone card, called Wellnavi (Matsushita Electric Works, Ltd, Osaka, Japan). SUBJECTS/SETTING: Twenty-eight college students majoring in food and nutrition in Okayama University of Japan voluntarily participated in this study. DESIGN: Applying a cross-sectional study design, participants were asked to keep 1-day weighed food records. Digital images of all recorded foods were obtained simultaneously and sent to registered dietitians by a mobile telephone card. The following day, a 24-hour recall was obtained. These procedures were repeated after 6 months. Participants' opinions about the three methods were determined using a questionnaire. STATISTICAL ANALYSIS: Differences in estimated median nutrient intake among the three methods were compared by Wilcoxon matched-pairs signed rank test. Relationships among the nutrient estimates by each method were evaluated using Spearman rank correlation coefficients. RESULTS: We found no significant differences between the Wellnavi method when compared with food records for most nutrients, except zinc, manganese, vitamin E, saturated fatty acid, polyunsaturated fatty acid, and dietary fiber. The median correlation coefficients for the nutrient estimates were 0.66 between the Wellnavi method and the food records. The survey showed that 57.1% of subjects considered the Wellnavi method the least burdensome of the three methods and the least time consuming (16 minutes) to record daily diet. About half of participants indicated that they would be willing to use the Wellnavi for 1 month to record their diet. CONCLUSIONS: This study suggests that a hand-held digital assistant may be a valid and convenient instrument for evaluating dietary intake.     

Validation of a food frequency questionnaire for assessing dietary nutrients in Brazilian children 5 to 10 years of age

OBJECTIVE: This study aimed to assess the relative validity of a food frequency questionnaire (FFQ), previously validated to measure usual intakes in adults, for measuring dietary intakes in children 5 to 10 y of age. METHODS: Dietary intakes were measured using an FFQ and a 3-d dietary record. Healthy children, 5 to 10 y old (n = 151), were recruited from public schools and asked to answer the questions in the FFQ and to provide non-consecutive 3-d dietary records based on reported estimated portion sizes. Paired sample t tests and Pearson's correlation coefficients were conducted to determine whether the two instruments reported similar values for energy and nutrients. The agreement of quartile categorization between the two instruments was also examined. RESULTS: Estimated energy and nutrient intakes derived from the FFQ were significantly higher than those derived from 3-d dietary records. As expected, Pearson's correlations increased after adjusting for residual measurement error, presumably due to exclusion of the high within-person variability in intake of these nutrients. Moderate to high (r > 0.50) correlation coefficients were verified for some nutrients such as calcium, folate, vitamin B2, vitamin A, and vitamin C. CONCLUSION: This FFQ, originally developed for use in adults, appears to overestimate usual energy and nutrient intakes in children 5 to 10 y of age. Further work is necessary to conduct a calibration study to establish adequate portion sizes before instrument adoption in this population.     

Reproducibility and validity of an expanded self-administered semiquantitative food frequency questionnaire among male health professionals.

The authors assessed the reproducibility and validity of an expanded 131-item semiquantitative food frequency questionnaire used in a prospective study among 51,529 men. The form was administered by mail twice to a sample of 127 participants at a one-year interval. During this interval, men completed two one-week diet records spaced approximately 6 months apart. Mean values for intake of most nutrients assessed by the two methods were similar. Intraclass correlation coefficients for nutrient intakes assessed by questionnaires one year apart ranged from 0.47 for vitamin E without supplements to 0.80 for vitamin C with supplements. Correlation coefficients between the energy-adjusted nutrient intakes measured by diet records and the second questionnaire (which asked about diet during the year encompassing the diet records) ranged from 0.28 for iron without supplements to 0.86 for vitamin C with supplements (mean r = 0.59). These correlations were higher after adjusting for week-to-week variation in diet record intakes (mean r = 0.65). These data indicate that the expanded semiquantitative food frequency questionnaire is reproducible and provides a useful measure of intake for many nutrients over a one-year period.     

Validation of a semi-quantitative food frequency questionnaire: comparison with a 1-year diet record

The validity of a self-administered semi-quantitative food frequency questionnaire was evaluated for a group of 27 men and women aged 20 to 54. Intakes of 18 nutrients computed from the questionnaire were compared with those derived from 1-year diet records completed approximately 18 months earlier. The questionnaire estimates of mean nutrient intake were within 10% of the mean diet record measurements for 11 of the 18 nutrients evaluated, and the difference was less than 25% for all but one nutrient (total vitamin A). Correlation coefficients comparing unadjusted nutrient intakes measured by the two methods ranged from 0.38 (vitamin C) to more than 0.65 (total calories, total fat, saturated fat, polyunsaturated fat, oleic acid, and cholesterol). The overall mean of correlation coefficients comparing intakes of the 18 nutrients measured by questionnaire and by diet record was 0.60. Coefficients for macronutrients decreased somewhat after adjustment for age and gender or caloric intake. The data provide further evidence that a simple and relatively inexpensive questionnaire can provide useful information on dietary intake over an extended period.     

The use of a self-administered questionnaire to assess diet four years in the past

The use of a mailed, self-administered, semiquantitative food frequency questionnaire to describe past dietary intake was evaluated in 1984 among a group of 150 Boston-area women who had completed four one-week diet records three to four years previously. Correlation coefficients comparing calorie-adjusted nutrient intakes computed from the questionnaire with those obtained from a compressed version of the questionnaire completed during diet record keeping ranged from 0.44 for total carbohydrate to 0.62 for vitamin C including supplements. Coefficients comparing calorie-adjusted nutrient intakes measured by questionnaire with those assessed by the diet records completed three to four years previously ranged from 0.28 for iron without supplements to 0.61 for total carbohydrate. An evaluation of the incremental contribution provided by several open-ended sections of the questionnaire to the estimation of nutrient intake suggested that in this population most of these items might be eliminated without material loss of information. These findings demonstrate that useful estimates of nutrient intake several years previously can be obtained by a relatively inexpensive, mailed, self-administered questionnaire.     

Dietary shortcomings in children on a gluten‐free diet

Background: Coeliac disease (CD), or permanent gluten intolerance, is one of the most common chronic food‐related diseases among children in Europe and the USA. The treatment is lifelong gluten‐free diet (GFD) (i.e. the exclusion of wheat, rye and barley from the diet, which are important sources particularly of iron, dietary fibre and vitamin B). The present study aimed to evaluate dietary intakes of energy and nutrients in children and adolescents on GFD and compare these with intake of comparable age groups on a normal diet as well as current recommendations. Methods: Thirty children, 4–17 years of age with confirmed CD and on GFD were agreed to participate in this study at the Department of Pediatrics, Umeå University Hospital. Weight and height were used to calculate individual energy requirement according to Nordic Nutrition Recommendations 2004 (NNR‐04). Dietary intake was assessed using 5‐day food records and household measures were used for quantities. Twenty‐five children completed their dietary record. Results: Thirteen of the 25 children did not meet the recommended energy intake and the dietary intakes were inadequate regarding quality of macronutrients and quantity of minerals and vitamins. The mean intakes of sucrose and saturated fatty acids were above and the intakes of dietary fibre, vitamin D, magnesium and selenium below the NNR‐04. High intakes of sucrose and saturated fat and a low intake of dietary fibre were also noted in a previous national survey on healthy children on a normal diet. The nutrient density of vitamin D, riboflavin, niacin, thiamine, magnesium and selenium were lower among CD children than healthy children but, for iron and calcium, it was higher in CD children. Conclusions: Children on GFD appear to follow the same trends as healthy children on a normal diet, with high intakes of saturated fat and sucrose and low intakes of dietary fibre, vitamin D and magnesium compared to recommendations.     

Diet diversity and nutrient intake

Variety is espoused as a key to dietary adequacy, yet data from new shortcut dietary measures suggest that intakes of relatively few foods can accurately classify individuals according to nutrient intake. This study examines diet diversity, caloric intake, and nutrient density values as contributors to the level of selected nutrients in the diets of 1,747 white men and 1,898 white women, 18 to 34 years old, completing the 24-hour recall in NHANES II. Nutrient intake was directly related to both number of foods eaten and total calories consumed, as well as to nutrient density values. For fat, saturated fat, and potassium, higher caloric consumption alone may account for substantial differences in nutrient intakes between the lowest and highest quartiles. For cholesterol, calcium, and vitamin A, differences in dietary density were more important in explaining nutrient intake differences. Both caloric intake and nutrient density influence sodium intake from food sources. For some nutrients, an overall measure of diversity may be useful for estimating intakes. For others, nutrient-specific diversity indexes would likely be needed. Knowledge of specific foods in diets with high levels of nutrients could aid the construction of food frequency instruments.     

Development of a simple food frequency questionnaire to estimate intakes of calcium and other nutrients for the prevention and management of osteoporosis

There have been no simple methods to estimate dietary nutrient intakes for the prevention and management of osteoporosis. The aim of this study was to develop and validate a new, simple food frequency questionnaire (FFQ) for dietary intake of calcium and other nutrients relevant to the bone health of adult Japanese women. We developed a 28-item FFQ. To validate this, 208 and 72 adult women aged between 18 and 69 y were recruited for testing reliability and reproducibility, respectively. In the 208 women, moderate-to-high Spearman's correlation coefficients between our FFQ and the conventional diet record method were found in intakes of calcium (r=0.668), sodium chloride (NaCl) (r=0.475), vitamin A (r=0.501), vitamin D (r=0.413), vitamin K (r=0.649), and energy (r=0.471). In the 72 women, coefficients of variance of the four repeated measurements of intakes throughout a year were 14.1% for calcium, 7.3% for NaCl, 21.2% for vitamin A, 13.6% for vitamin D, 36.8% for vitamin K, and 9.6% for energy. In conclusion, the FFQ we developed is a useful tool to evaluate the intake of dietary calcium of adult Japanese women. Although it can also measure intakes of dietary vitamin A, vitamin D, vitamin K, NaCl, and energy, further improvement is needed to measure intakes of these nutrients and energy.     

The nutrient intakes of pregnant and lactating mothers of good socio-economic status in Cambridge, UK: some implications for recommended daily allowances of minor nutrients

1. Forty-two mothers from social classes I, II and III non-manual and twenty-one from social classes III manual M), IV and V were studied longitudinally. The mean daily nutrient intakes in months 4-9 of pregnancy, months 2-4 of lactation and 3 and 6 months post-lactation are presented and are compared with the UK and the US recommended daily allowances (RDA). 2. The quality of the diets (nutrients per 4184 kJ (1000 kcal] was found to be better than that of other adult female populations studied in the UK, except for a group of dietitians. 3. The mean daily intakes of nutrients for which there are UK RDA were almost all greater than 100% of the RDA. The exceptions were iron, which in the manual group (social classes IIIM, IV and V) was 85% of the RDA in pregnancy and 75% post-lactation, and vitamin D. 4. Among the nutrients for which there are US, but not UK RDA, only phosphorus and vitamin B12 intakes were greater than 100% of the RDA in both groups at all stages of the study. Intakes of other nutrients were below the RDA: pantothenate 70-91, vitamin B6, zinc, vitamin E and copper 40-72, folate 21-44, and biotin less than 20% of the RDA. 5. The bases of the RDA for adult women were examined; for most nutrients the information is limited. It was concluded that the RDA for magnesium, vitamin E and pantothenate are probably higher than necessary and that deficiency is unlikely; that zinc, copper, vitamin B6 and folate are probably 'marginal' nutrients for 'at risk' groups; and that information on biotin is insufficient even roughly to assess the dietary requirement.     

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

In prospective studies of diet it is often necessary to know for how many days subjects should record food consumption in order to be able to rank subjects correctly according to their nutrient intakes. Data from six studies--of toddlers, families, schoolchildren, dietitians, pregnant women, and elderly subjects--were analyzed to estimate the number of recording days necessary for energy, 28 nutrients, and the ratio of polyunsaturated to saturated fatty acids (P:S). The most striking finding is that 7 d of diet record do not rank subjects with the degree of accuracy commonly assumed. For some nutrients, such as iron, zinc, nicotinic acid, and pyridoxine, it may be desirable to record diet over a number of short, separate periods to achieve the number of days required. For others, such as copper, retinol, carotene, vitamin B-12, polyunsaturated fatty acids, P:S, and alcohol, alternative methods of assessment based on dietary histories or questionnaires may be more appropriate.     

Variability in estimation of self-reported dietary intake data from elite athletes resulting from coding by different sports dietitians

A routine activity for a sports dietitian is to estimate energy and nutrient intake from an athlete's self-reported food intake. Decisions made by the dietitian when coding a food record are a source of variability in the data. The aim of the present study was to determine the variability in estimation of the daily energy and key nutrient intakes of elite athletes, when experienced coders analyzed the same food record using the same database and software package. Seven-day food records from a dietary survey of athletes in the 1996 Australian Olympic team were randomly selected to provide 13 sets of records, each set representing the self-reported food intake of an endurance, team, weight restricted, and sprint/power athlete. Each set was coded by 3-5 members of Sports Dietitians Australia, making a total of 52 athletes, 53 dietitians, and 1456 athlete-days of data. We estimated within- and between- athlete and dietitian variances for each dietary nutrient using mixed modeling, and we combined the variances to express variability as a coefficient of variation (typical variation as a percent of the mean). Variability in the mean of 7-day estimates of a nutrient was 2- to 3-fold less than that of a single day. The variability contributed by the coder was less than the true athlete variability for a 1-day record but was of similar magnitude for a 7-day record. The most variable nutrients (e.g., vitamin C, vitamin A, cholesterol) had approximately 3-fold more variability than least variable nutrients (e.g., energy, carbohydrate, magnesium). These athlete and coder variabilities need to be taken into account in dietary assessment of athletes for counseling and research.     

The reliability of ten-year dietary recall: implications for cancer research

Remote dietary intakes may be more important than recent diet in the etiology of cancer because of the long latency in cancer development. We examined the reliability of remote dietary recall over 10 y. Subjects were 56 adults participating in a cancer prevention trial in Western Australia. All subjects completed a 28-d diet record (DR) in 1991. A food-frequency questionnaire (FFQ) modified to ask respondents about their diet 10 y earlier was sent to each subject for completion in 2001. Remote intakes recalled from 10 y earlier using the FFQ were compared with the DR using the limits of agreement (LOA) method and Pearson correlation coefficients. Mean intakes of most nutrients did not differ between dietary methods. The LOA indicated that the FFQ could under- or overestimate DR estimates by >/=50%. For many nutrients, agreement between methods depended on the magnitude of intake. Pearson's correlation coefficients ranged from 0.02 for retinol to 0.66 for alcohol. These findings are similar to those of other studies that examined the reliability of recent and remote dietary intakes. They also show that using this FFQ, remote diet recalled from 10 y earlier may be as reliable as recent dietary recall.     

Validation of a Food Frequency Questionnaire in Native American and Caucasian Children 1 to 5 Years of Age

Objective: To assess the validity of the Harvard Service Food Frequency Questionnaire (HFFQ) in the diet assessment of Native American and Caucasian children 1 to 5 years of age participating in the North Dakota WIC program. Methods: The 84-item HFFQ was administered twice to the parent or guardian of 131 Native American and 102 Caucasian children ages 1 to 5 years (total n = 233), first at the child's routine WIC visit and then following the completion of three 24-hr dietary recalls taken over approximately 1 month. Average nutrient intakes from the three 24-hr dietary recalls were compared to average nutrient intakes from the HFFQs by calculating Pearson correlation coefficients and adjusting for energy intake and within person variation. Results: Correlation coefficients ranged from 0.26 for dietary fiber to 0.63 for magnesium. The average correlation was 0.52, similar to that found in validation studies among adolescents and adults. The following nutrients had correlations of 0.50 or greater: carbohydrate, sucrose, total fat, vitamin C, vitamin E, vitamin Bl, vitamin B2, niacin, folate, vitamin B6, calcium, magnesium, and iron. Conclusions: The HFFQ is a simple self-administered questionnaire completed by the child's parent or guardian and is useful in assessing the diets of Native American and Caucasian children. It may also provide important nutritional information about this age group for future program planning, research, education, and intervention purposes.     

The growth and development of vegan children

The results of prospective study on the growth and diets, estimated from 7-day weighed food intake records, of 20 life vegan children (aged 5.8–12.8 years) are presented. The growth and development of the children were normal but they tended to be lighter in weight and exceptionally lean compared with standards. Heights were around the median of the Tanner-Whitehouse standards but were lower than the medians recently proposed by the Department of Health. Energy intakes were similar to those reported in children of the same age in the general population, but dietary fibre intakes were very high which may have influenced the digestible energy. Sugar provided an average 15.6% of the dietary energy and this was supplied mainly by fruit and fruit juice. Mean fat intakes were close to the dietary reference values. Daily intakes of essential nutrients generally met the amounts recommended, with the exceptions of calcium and vitamin B₁₂. Many children received supplementary sources of vitamin B₁₂ and only two children had intakes below the lower recommended nutrient intake. Intakes of saturated fatty acids were low and those of linoleic acid were high. The ratio of linoleic/α-linolenic acid was high. As docosahexaenoic acid is absent from vegan diets, it is suggested that vegans should use oils with a lower ratio of linoleic/α-linolenic acid. Future studies should also consider the influence of a vegan diet on retinal function. None of the children was immunized against whooping cough and 11 had not been immunized against polio: 16 of the children had suffered from whooping cough. Future studies need to take into account factors other than diet when assessing the health of vegans. The results of this study show that children can be successfully reared on a vegan diet providing sufficient care is taken to avoid the known pitfalls of a bulky diet and vitamin B₁₂ deficiency.     

A two-year dietary survey of middle-aged women: repeated dietary records as a measure of usual intake

A two-year survey of the dietary consumption and supplement use patterns of adult women was conducted at the University of Wisconsin-Madison. Participants were asked to record their diet on two randomly selected days per month over a two-year period. Each subject filled out an average of 19 records a year, for an overall 71% return rate. Because of the sampling design, it was possible to estimate each woman's "usual" or average daily dietary and total intake (diet plus supplements) of 15 nutrients. Many women were consuming usual amounts of energy, calcium, iron, magnesium, vitamin B-6, and, especially, zinc and total folate that were 30% to 50% below recommended levels. It was also found that the women generally took vitamin/mineral supplements for nutrients already adequately supplied in the diet. Low nutrient intakes may have been due, in part, to underreporting of food intakes.     

Nutrient intake of low-income Southeast Asian pregnant women

Dietary nutrient intakes of 91 Cambodian, 37 Laotian, and 59 Vietnamese low-income pregnant women attending a university teaching hospital outpatient clinic in Southern California were measured. The nutrient intakes of the Southeast Asian groups were compared with one another as well as with the intakes of a group of 165 low-income non-Southeast Asian pregnant women of similar height, weight, and age from the same outpatient clinic population. Computerized analysis of the 24-hour recall data showed that there were few differences in nutrient intake between the Southeast Asian groups, except that the Cambodian group consumed significantly less fat, riboflavin, vitamin D, and calcium than the Vietnamese group. However, there were a number of differences between the nutrient intakes of the Southeast Asian groups and those of the non-Southeast Asian group. These included significantly lower intakes of fat, riboflavin, folate, vitamins D and E, calcium, phosphorus, potassium, and magnesium and significantly higher intakes of thiamin, niacin, sodium, and selenium. These findings suggest that low-income Southeast Asian pregnant women have some good dietary habits that dietitians need to reinforce and other dietary habits that need improvement.     

Dietary intake of a representative sample of the population of Val-de-Marne; III. Mineral and vitamin intake

Mineral and vitamin intakes were assessed among 1108 subjects, aged 6 months to 97 years in 12 of 47 towns and cities in the district of Val-de-Marne (Paris area), using the telephone directory as random sampling base. Micronutrients intake was evaluated by individual interviews at home by specialized dietitians (dietary history method). Mineral and vitamin intake was found to vary widely with age. In absolute value, overall mineral and vitamin dietary intakes was higher in men than in women (except for vitamin C). Conversely, the dietary density for mineral and vitamins was higher in females. For a large part of the studied population, it would appear difficult to satisfy recommended dietary allowances for many micronutrients (iron, zinc, vit. B1, B6, C, A et E). These results bring to light possible difficulties in covering certain mineral and vitamin requirements in the French population.     

Comparison of a food frequency questionnaire using reported vs standard portion sizes for classifying individuals according to nutrient intake

Individual intakes of retinol, carotene, vitamin C, and folacin calculated from a food frequency questionnaire using reported portion size were compared with intakes calculated using standard portion size information. Data from a case-control study to determine the association of nutrient intake and risk of cervical dysplasia were supplemented by standard portion size information from the US Department of Agriculture and reanalyzed. Significant mean differences were found between intake calculated from reported portion size data and that calculated from standard portion size data for all nutrients. Correlation of nutrient intakes obtained by the two methods of data collection ranged from .73 to .92. Calculation of the rho statistic, measuring the consistency of classification of participants into groups of high, medium, and low nutrient intake, led to values ranging from .55 to .71, indicating some misclassification of study participants. To determine the effect misclassification had on the study outcome, odds ratios were calculated using nutrient amounts obtained from both methods of collecting portion size data. Results indicate that replacing reported portion size data with standard portion size data may lead to conflicting outcomes for specific nutrients in research concerning the relationship between diet and disease.