Vitamin and mineral intakes of Anglo-American and Mexican-American preschoolers

Overview of methods used to evaluate the adequacy of nutrient intakes for individuals and populations

The objective of the present paper is to review the methods of measuring micronutrient intake adequacy for individuals and for populations in order to ascertain best practice. A systematic review was conducted to locate studies on the methodological aspects of measuring nutrient adequacy. The results showed that for individuals, qualitative methods (to find probability of adequacy) and quantitative methods (to find confidence of adequacy) have been proposed for micronutrients where there is enough data to set an average nutrient requirement (ANR). If micronutrients do not have ANR, an adequate intake (AI) is often defined and can be used to assess adequacy, provided the distribution of daily intake over a number of days is known. The probability of an individual's intake being excessive can also be compared with the upper level of safe intake and the confidence of this estimate determined in a similar way. At the population level, adequacy can be judged from the ANR using the probability approach or its short cut – the estimated average requirement cut-point method. If the micronutrient does not have an ANR, adequacy cannot be determined from the average intake and must be expressed differently. The upper level of safe intake can be used for populations in a similar way to that of individuals. All of the methodological studies reviewed were from the American continent and all used the methodology described in the Institute of Medicine publications. The present methodology should now be adapted for use in Europe.

Nutrition provided to Mexican-American preschool children on the Texas-Mexico border

The purpose of this study was to assess whether nutrients offered to border Mexican-American preschool children met the Recommended Dietary Allowances. Nutrient contents of two dietary patterns were examined in this study, one composed exclusively of home foods and one containing a combination of both home and school foods. The sample consisted of 198 Mexican-American preschoolers living on the Texas-Mexico border, who were recruited using a convenience sampling technique. A self-administered, precoded 24-hour recall questionnaire was used. Nutrient values of home foods were collected during a weekend day, and nutrient values containing a combination of both home and school foods were collected during a weekday. Fisher's exact test or chi2 test and t test were used for analyses. Mean nutrient contents of foods provided to the border Mexican-American children exceeded recommendations for total energy (P<0.001), total fat (P<0.001), saturated fat (P<0.001), carbohydrates (P<0.001), protein (P<0.001), sodium (P<0.001), and niacin (P<0.001). Foods offered were also significantly insufficient in fiber (P<0.001), vitamin A (P<0.001), and potassium (P<0.001). Nutrition interventions targeting low-income border Mexican-American families should emphasize the need and importance of providing children with diets that meet the Recommended Dietary Allowances.

Nonsupplemented children of Latino immigrants have low vitamin E intakes and plasma concentrations and normal vitamin C, selenium, and carotenoid intakes and plasma concentrations

OBJECTIVE

This study sought to determine and evaluate the intakes and plasma concentrations of vitamin E (alpha-tocopherol), gamma-tocopherol, vitamin C, selenium, and carotenoids (alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin, and lycopene) of nonsupplemented boys and girls, 4 to 8 years old, of Latino immigrants living in rural Nebraska.

DESIGN

Dietary intakes of the Latino children were estimated. Their plasma samples (fasting) were analyzed for vitamin E, vitamin C, selenium, and carotenoid concentrations. Data were evaluated by sex.

SUBJECTS

The subjects were a convenience sample of 4- to 8-year-old (n=29), apparently healthy, nonsupplemented children of Latino immigrants living in rural Nebraska.

STATISTICAL ANALYSIS

Sex differences in parameter values were determined using general linear models; Pearson r was used for determining correlations.

RESULTS

No significant differences in parameter values were observed by sex, with the exception of plasma lutein/zeaxanthin concentration. The majority (69%) had plasma vitamin E (alpha-tocopherol) concentrations<0.516 mg/dL (12 micromol/L), which is indicative of vitamin E inadequacy, and over half (59%) reported consuming less than the Estimated Average Requirement for vitamin E. All subjects had plasma vitamin C and selenium concentrations indicative of adequacy (>0.41 mg/dL or >23 micromol/L, and >6.32 microg/dL or >0.8 micromol/L, respectively), and consumed at least the Recommended Dietary Allowances for these nutrients. The plasma carotenoid concentrations of the children may be useful as norms.

CONCLUSIONS

These children of Latino immigrants who did not take supplements had low plasma vitamin E (alpha-tocopherol) concentrations but normal plasma vitamin C and selenium concentrations.

IMPLICATIONS

Dietetics professionals and others involved in health care need to work with Latino immigrant parents so that their children consume adequate amounts of vitamin E.

Factors associated with Hb concentration in children aged 6-59 months in the State of Pernambuco, Brazil

In 1997, the prevalence of anaemia was 40.9 % among children aged 6-59 months in the State of Pernambuco, north-east Brazil. Using the same sample of children, we have investigated possible reasons for this high prevalence. A representative sample was selected through a three-stage process: proportional systematic random sampling of municipalities in the State, systematic random sampling of census sectors within these municipalities, and finally, simple random sampling of households with children aged 6-59 months to obtain the sample of 650 children. Data collection included demographic, environmental, socio-economic and maternal variables, and nutritional status and dietary intakes of the children. Multiple linear regression analysis was based on a hierarchical model of factors associated with Hb concentration. The mean Hb concentration of children aged 6-23 months was 10 g/l lower than that of older children. In the regression analysis, child age explained 8.3 % of the variance in Hb concentration. The intake of bioavailable Fe explained a further 3.3, serum retinol 2.7, diarrhoea 2.4, water treatment 1.7, sanitation 1.3 and low birth-weight 0.5 %. The final model explained 23.4 % of the variance in Hb concentration. We conclude that child age, bioavailable-Fe intake, serum retinol concentration, diarrhoea, water treatment, sanitation and low birth-weight are independently associated with Hb concentration. In north-east Brazil, anaemia prevention programmes among children should focus on those aged <2 years and should consider feasible strategies to improve intakes of bioavailable Fe and vitamin A, and reduce infection. Supplemental Fe should be given to low birth-weight infants.

A comparison of nutrient intake between infants and toddlers with and without cystic fibrosis

OBJECTIVE

To compare the micronutrient and energy intake of infants and toddlers with cystic fibrosis (CF) to the intake of matched control children and dietary reference index (DRI) levels.

DESIGN

A two-group comparison study. Nutrient and energy intakes were measured via 3-day diet diaries. Anthropometric data were collected within 1 week of study enrollment.

SUBJECTS/SETTING

A clinical sample of 35 infants and toddlers with CF (mean=18.6, SD=8.1 months) matched to a community sample of 34 healthy controls.

STATISTICAL ANALYSES PERFORMED

Children with CF and controls were compared on anthropometric and nutrient data using independent sample t tests. Mean nutrient and energy intake for children in each group were compared with the age-appropriate DRI for targeted nutrients using percentages.

RESULTS

Children with CF and controls were similar on measures of growth (height, weight, or weight-for-height percentile). Four children with CF were at or below the 10th percentile for weight-for-height, compared with one control child. Children with CF and controls did not differ on average daily protein, calcium, zinc, and energy intake. Overall, children met or exceeded DRI levels for nutrient intakes. A notable exception was iron, for which mean intakes were lower for control children. Toddlers with CF consumed only 89% of the RDA per day for energy.

APPLICATIONS/CONCLUSIONS

Infants and toddlers with CF are likely obtaining adequate micronutrient intakes from food. Interventions to increase total energy intake in infants and toddlers with CF are needed. Dietitians may want to focus more on calorie intake and percent calories from fat than on micronutrient intake in their nutrition counseling in young children with CF.

Longitudinal study of energy and nutrient intakes for infants from low-income, urban families

OBJECTIVE

To assess the energy and nutrient intakes of healthy infants from low-income families and to compare intakes with current recommendations.

DESIGN

We interviewed mother-infant pairs longitudinally when the infants were 3, 6, 9, 12, 18 and 24 months old. Food intake data were obtained by 24-hour dietary recalls. Selected nutrient intakes were calculated and compared with the Recommended Dietary Allowances (RDAs).

SUBJECTS/SETTING

Infants were the offspring of low-income, pregnant women recruited at the Albany County Department of Health, New York for the Albany Pregnancy and Infancy Lead Study, a prospective investigation of factors related to blood lead levels, including nutrition. Interviews were conducted during paediatric clinic visits.

STATISTICAL ANALYSES PERFORMED

Means and standard deviations were used to describe energy and micronutrient intakes for age groups. The probability approach was utilised to examine the prevalence of inadequate intakes.

RESULTS

Mean energy and nutrient intakes generally met or exceeded the RDA. The exceptions were vitamin D and zinc for which observed means were below the RDA at several data points. Protein consumption was exceptionally high in this sample. The highest estimated prevalences of inadequate intakes were observed for iron, zinc and vitamin D at the older ages.

CONCLUSIONS

This study identified several potential concerns about the diets of infants during the transition from infant food and formula to table foods. Low intakes of vitamin D, zinc and iron, especially at 12 and 18 months, were observed. High protein intakes were noted at all ages.

Dietary intakes of selected elements from longitudinal 6-day duplicate diets for pregnant and nonpregnant subjects and elemental concentrations of breast milk and infant formula

As part of a longitudinal investigation into mobilization of lead from the maternal skeleton during pregnancy and lactation, we have determined the daily intake of selected elements (hereafter called micronutrients) for various subjects and compared these intakes with recommended and/or published intakes, especially those of the United States, through the U.S. National Health and Nutrition Examination Survey (NHANES). We also sought to ascertain whether there was any seasonal effect in the diets. Six-day duplicate diets were collected from 15 pregnant and 16 nonpregnant migrants to Australia, 6 pregnant Australian control subjects, and 8 children of nonpregnant migrants (6 to 11 years). Samples of breast milk and infant formula were also analyzed. Blended samples were analyzed by inductively coupled plasma mass spectrometry for the elements Ca, Cu, Fe, Mg, P, K, Na, Zn, Ba, Sr, and Pb. Daily intakes of micronutrients were only about half of the daily intake estimated for non-Hispanic white females and infants in the U.S. NHANES III. Estimates of daily intakes from breast milk were also considerably lower for the migrant and Australian infants compared with the values extracted from tables of food composition and dietary recall for non-Hispanic white infants in the U.S. NHANES III. For example, Ca was a factor of approximately 3 times lower, Fe approximately 50, and Zn approximately 4. We consider our estimates a reliable indication of the daily intakes for several reasons, including the collection of up to nine quarterly collections of 6-day duplicate diets and retention of subjects in a longitudinal prospective study. The low intakes of the essential elements such as Ca, Fe, and Zn in all these population groups are of potential concern from a public health viewpoint.

Longitudinal study of nutrient and food intakes of white preschool children aged 24 to 60 months

OBJECTIVE

To determine nutrient and food intakes of 72 white preschool children primarily from families of middle and upper socioeconomic status and to compare children's nutrient intakes with current recommendations.

DESIGN

Six in-home interviews were conducted with mothers when children were 24 to 60 months old; at each time mothers provided 3 days of dietary information on the child. Children and mothers independently provided information on the child's favorite and least favorite foods at 42 and 54 months.

SUBJECTS

Preschool children (24 to 60 months old) participating in a longitudinal study.

STATISTICAL ANALYSES

Mean nutrient intakes were compared with the most recent Recommended Dietary Allowances/Adequate Intakes. Differences over time were tested with repeated-measures analysis of variance; gender differences were determined with t tests. Food frequencies (i.e., percentage of children consuming specific foods) were determined from dietary recalls and food records. Dietary variety was assessed with the Variety Index for Toddlers or the Variety Index for Children.

RESULTS

Means were consistently less than the RDA/AI for energy, zinc, folate, and vitamins D and E. Energy, carbohydrate, and fat intakes were highest (P < or = .01) at 60 months. Boys consumed more (P < or = .05) protein (10 g), calcium (197 mg), magnesium (35 mg), and pantothenic acid (0.8 mg) at 60 months than did girls. Foods most commonly eaten were fruit drink, carbonated beverages, 2% milk, and french fries. The vegetable group consistently had the lowest variety scores; vegetables also dominated least favorite foods lists.

APPLICATIONS

Parents need to be encouraged to include more sources of zinc, folate, vitamin E, and vitamin D in children's diets. Parents should also encourage their children to eat more vegetables, zinc- and folate-fortified cereals, lean red meats, seafood, vegetable oils, and low-fat milk.

Nutrient intake of Head Start children: home vs. school

OBJECTIVE

To determine mean intake of energy and protein, total fat, saturated fat, percent energy from total and saturated fat, cholesterol, carbohydrate, calcium, iron, zinc, folate, vitamins A, C, E, B-6 and B-12, thiamin, niacin, riboflavin, magnesium, sodium and fiber of preschool Head Start children at school and away from school.

DESIGN

Twenty-four-hour food intakes for 358 Head Start children were obtained by observing food intake at school and acquiring intake recalls from parents or guardians specifying food their children consumed for the balance of the day. After determining group estimates of energy and nutrient intake, mean intake was compared to standard nutrient recommendations for the entire 24-hour day, i.e., for the time the children were in school and for the remaining hours away from school ("home" intake).

SUBJECTS

The 358 Head Start children attended school either half-day (2- to 3-hour AM and PM sessions) or all-day (5 to 6 hours).

STATISTICAL ANALYSES

Differences in nutrient intake among class times were analyzed using one-way analysis of variance (ANOVA) followed by Tukey's multiple comparison test. Differences with a p-value <0.05 (two-tailed) were considered to be statistically significant. Total energy, protein, calcium, iron, zinc, vitamins A, C, E, B6, and B12, thiamin, niacin, riboflavin as well as folate and magnesium were compared to the Recommended Dietary Allowances for the 4- to 6-year-old age group. Other standards that were used for comparisons included the National Cholesterol Education Program (fat, saturated fat and cholesterol), the 1989 National Research Council's Diet and Health Report (carbohydrate and sodium) and the recommendation for fiber proposed by the American Health Foundation.

RESULTS

At school, half-day children consumed up to 25% of the daily recommendation for energy and nutrients, while all-day children achieved at least a third of the recommended intakes. When intakes at home and school were combined, all three groups of children (AM, PM and all-day) exceeded dietary recommendations for protein, vitamins and minerals. Energy intake remained below 100% of the recommendation, while intake of total fat, saturated fat and cholesterol exceeded recommendations.

APPLICATION

Further research is required to explore energy needs and determine nutritional status and nutrient needs of minority and low-income preschool children. Strategies are required to increase nutrient density, but not fat density, of meals and snacks served to children who attend day care for part of the day. Finally, school meals and nutrition education programs such as Team Nutrition should broaden their base to include healthful eating habits for all school children, including the very youngest children in preschool programs.

The effect of changes in dietary fat on the food group and nutrient intake of 4- to 10-year-old children

OBJECTIVE

To determine how young children changed their overall diet when they changed their fat intake after 3 months of participating in a nutrition education demonstration study designed to lower low-density lipoprotein cholesterol and cardiovascular risk.

METHODS

Three 24-hour dietary recalls were collected from 303 4- to 10-year-old children at baseline and 3 months later. At both times, mean number of servings from food groups, grams of fat contributed from food groups, and intake of calories and nutrients were calculated and compared among quartiles of children formed according to change in their percent of calories from total fat after 3 months.

RESULTS

Children who reduced their percent of calories from total fat most (ie, by an average of 8.5%) after 3 months consumed fewer servings from meats, eggs, dairy, fats/oils, and breads but tended to increase their number of servings from lower-fat foods within those food groups, particularly from dairy foods. These children also increased their mean intake of fruits, vegetables, and desserts, and maintained average intakes of all nutrients (except vitamin D) in excess of two thirds of the respective recommended dietary allowance.

CONCLUSIONS

Young children who reduced their percent of calories from total fat in accordance with the current National Cholesterol Education Program recommendations accomplished this by reducing their overall intake of higher-fat foods, replacing higher-fat foods with lower-fat foods within several food groups, particularly within the dairy group (eg, drinking skim milk instead of whole milk) and by consuming more servings of fruits, vegetables, and very-low-fat desserts. These behaviors did not compromise their mean calorie or nutrient intakes, showing that it is possible for young children to lower their fat intake safely to reduce their risk of future heart disease.

Nutrient patterns and nutritional adequacy among French-Canadian children in Montreal

OBJECTIVES AND METHODS

A representative sample of French Canadian Montrealers was surveyed to compile data on food habits, nutrient intakes and sociodemographic characteristics, using interviewer-administered questionnaires and 7-day food records (7D-FR).

RESULTS

Complete 7D-FR and sociodemographic data were obtained from 614 adults aged 19 and over (40.1% males), and 182 children aged 5 to 18 (44.8% males). Average heights and weights of children were at the 50th percentile for both sexes and all age groups. Nutrient intakes surpassed most of the age- and sex-specific 1990 Canadian Recommended Nutrient Intakes (RNIs). Energy intakes were 83% to 98% of the RNIs, with 16-18 year old adolescent girls having systematically lower energy consumption. Calcium was most frequently found below the 66% age-sex specific RNI cut-off. On average, protein comprised 16% of energy, fat 36-37%, and carbohydrates 48-49%, for males and females, respectively. Simple sugars comprised 16-19% of energy among boys, and 16-20% among girls, fluctuating with age. Only a small proportion of respondents (15.4%) had low relative total fat and saturated fat intakes (ranging from 30-34%, and 10-12% of energy, respectively); no differences in mean nutrient levels were found between low, medium or higher fat consumers. Among those with inadequate intakes, 26% lived in one lower middle income sector of Montreal; however, no clear pattern emerged linking dietary adequacy and socioeconomic factors.

CONCLUSIONS

While Montreal youngsters consume generally adequate diets, sufficient quantities of calcium-furnishing foods must be eaten, particularly by adolescent girls. Surveillance of children's food and nutrient intakes will contribute to the reduction of chronic disease by providing data for effective health care planning.