A systematic review of dietary assessments of pregnant adolescents in industrialised countries

Adolescent pregnancy is a major public health challenge for many industrialised countries and is associated with significant medical, nutritional, social and economic risk for mothers and their infants. Despite this, relatively little is known about the nutrient intakes of adolescents during pregnancy. The aim of this study is to review the current evidence relating to the dietary assessment of pregnant adolescents living in industrialised countries. Nine papers were identified that fulfilled the inclusion criteria, seven of which were conducted in the USA. Mean nutrient intakes were compared with the most recent US dietary reference intakes (DRI) for pregnant adolescents. Despite the poor quality of the majority of studies, there appeared to be some consensus to suggest that the nutrient intakes of pregnant adolescents were below the DRI for energy, iron, folate, calcium, vitamin E and magnesium, nutrients which are recognised to be vital for fetal growth and development during pregnancy. Modest differences were observed in nutrient intake between trimesters and age groups. Current research is limited by sampling and measurement bias, and research is urgently required to address these limitations. Further consideration should also be made of the influence of age and of role of socio-economic support on pregnant adolescents' nutrient intake. The achievement of improved nutrition in pregnancy among adolescents requires multidisciplinary collaborations of adolescent health care providers, academics, professional organisations, policy makers, industry and service users. Only once this is achieved can adolescent nutrition, and adolescent nutrition in pregnancy, be significantly and sustainably optimised.     

Food-based dietary guidelines: some assumptions tested for The Netherlands

Recently, the concept of food-based dietary guidelines has been introduced by WHO and FAO. For this concept, several assumptions were necessary. The validity and potential consequences of some of these assumptions are discussed in this paper on the basis of the Dutch National Food Consumption Surveys. The topics were interrelationships among dietary characteristics, nutrient density, diets in accordance with the guidelines, and food variety. To obtain insight into overall diet quality, a dietary quality index based on nutrients and a food-based quality index based on food groups were created and tested. As expected the results showed that a higher dietary quality index was associated with an improved intake of the nutrients included in the index, in particular a lower intake of total fat and cholesterol. This was related to a lower consumption of cheese, fats and oils, meat and meat products, and a higher consumption of fruit and vegetables. The information obtained with a dietary quality index can be used to assess the feasibility of a particular goal in combination with other relevant goals and to obtain clues or confirmation for recommendations regarding food consumption. The food-based quality index created showed that a combination of several food-based goals (formulated in quantitative terms) was associated with an increase in food consumption, without a clear relevance for the dietary quality. Therefore, the formulation of food-based guidelines should be based on explicitly stated dietary goals. The findings regarding nutrient density were in the direction of what was assumed, namely a positive association between density and absolute intake, although the expected effects were not completely found. The results regarding the association between variety and dietary intake were characterized mainly by differences in quantity rather than dietary quality. The data indicate that energy intake may be an important pitfall in implementing food-based dietary guidelines, that 'eat a variety of food' can be an empty slogan and that nutrient density is positively related to the absolute intake of specific micronutrients. Further, the 'absence' of interrelationships among risk nutrients indicates that a selection process has to be applied.     

Pregnant adolescent and adult women have similarly low intakes of selected nutrients

OBJECTIVE: To examine the dietary intake of pregnant adolescents during the second and third trimester of pregnancy, and to compare their nutrient intake with that of pregnant adults. DESIGN: Two 7-day food records (14 days) from subjects participating in a larger randomized clinical calcium trial: the first at 19 to 21 weeks and the second between 29 and 31 weeks gestation. Intake of energy and selected nutrients were calculated and compared with dietary standards. SUBJECTS/SETTING: Fifty-nine pregnant adolescents and 97 pregnant adults recruited from prenatal clinics at a metropolitan university hospital. STATISTICAL ANALYSES: Two sample t tests, equality of variances, and repeated measures (analysis of variance). RESULTS: There was no difference in mean nutrient intakes between the second and third trimesters. Using two 7-day food records, we found mean intakes for energy, iron, zinc, calcium, magnesium, folate, and vitamins D and E to be below recommended standards in both groups. Other nutrients examined met or exceeded reference values. Total daily intakes for energy and 11 nutrients were significantly higher in the adolescent compared to the adult diets (P < .05). These differences were not evident when nutrient values were corrected for energy, indicating that increased energy intake in the teen-aged population was contributed by nutrient-dense foods. APPLICATIONS: This study indicates the need for continued dietary monitoring of pregnant adolescents and pregnant adults, including nutrition guidance that stresses food sources of calcium, magnesium, zinc, iron, fiber, folate, and vitamins D and E, the nutrients found deficient in their diets.     

Dietary patterns in pregnancy and associations with nutrient intakes

Despite the recent popularity in the use of dietary patterns to investigate diet-disease associations, the associations between dietary patterns and nutrient intakes have not been fully explored. This paper determines the linear and non-linear associations between estimated nutrient intake (considered as both absolute and relative intake) and distinct dietary patterns, obtained during the third trimester of pregnancy using principal components analysis (PCA). It also examines the proportion of variability explained by the patterns in food and nutrient intakes. Pregnant women were asked to record the frequency of consumption of a variety of food items as part of regular self-completion questionnaires, the primary source of data collection in the Avon Longitudinal Study of Parents and Children, 12 035 cases were available. Individual dietary components were identified using PCA and scores on these components were related to estimated nutrient intakes. Five individual dietary patterns were established to best describe the types of diet being consumed in pregnancy. Scores on the 'processed' and 'confectionery' patterns were negatively related to the estimated intake of most nutrients with the exception of energy, fats and sugars, which increased with higher scores. Scores on the 'health-conscious' and 'traditional' components showed positive linear relationships with all nutrients. The results presented here suggest that dietary patterns adequately characterize dietary intake. There is, therefore, potential for dietary patterns to be used as a valid tool in assessing the relationship between diet and health outcomes, and dietary pattern scores could be used as covariates in specific nutrient-disease studies.     

Computerized dietary analysis by food groups and by nutrients from food groups

The professional responsibility of dietetic and nutrition educators and counselors is to provide clients and the public with accurate, understandable information and counseling concerning the relationship of diet to health and disease. Dietary guidance expressed as energy and nutrient content is clear to the nutrition professional, but it frequently is difficult for many clients to comprehend. This study was undertaken to develop a computer software program to analyze dietary data in terms of foods, food groups, and nutrients and to discuss the applications of the computerized assessment. Dietary recalls from a group of noninstitutionalized older women were used for illustrative purposes. Dietary intakes were described in terms of servings consumed of 9 major food groups and 39 major subgroups. Intake of energy and selected nutrients from each major food group was calculated. Recalls were evaluated by comparison with recommended servings from two food guides and recommended energy and nutrient allowances. The information elicited by the software package is useful for monitoring changes in food consumption patterns, assessing dietary compliance, planning, and evaluating nutrition and feeding programs.     

Nutrient intake and food consumption among pregnant women from an agricultural region of Morocco

This study aimed to assess dietary intake and nutrient adequacy in pregnant women selected from an agricultural region of Morocco. On a sample of 172 pregnant women from rural and urban area, data on socio-demographic characteristics and dietary habits by a quantified food frequency were collected using questionnaires. Mean daily intakes of energy and nutrients were estimated and compared to reference nutrient intakes (RNI). The results show that the mean daily intakes of energy (3110.9 kcal in urban; 2707.5 kcal in rural) and some nutrients were adequate. However, iron, folate, zinc and calcium intakes were inadequate for the majority of women and more markedly in rural area. Education level appeared to affect nutrient intakes while no differences were registered across pregnancy stages or according to household size. The study suggests that an education program should be conducted to improve dietary intakes in order to prevent risks for pregnancy outcome in this population.     

Adult recall of adolescent diet: reproducibility and comparison with maternal reporting

Many cancers have long latency periods, and dietary factors in adolescence may plausibly affect cancer occurrence in adulthood. Because of a lack of prospective data, retrospective collection of data on adolescent diet is essential. The authors evaluated a 124-item high school food frequency questionnaire (HS-FFQ) assessing diet during high school (15-35 years in the past) that was completed in 1998 by 45,947 US women in the Nurses' Health Study II (NHSII) cohort. To assess reproducibility, the authors readministered the HS-FFQ approximately 4 years later to 333 of these women. The mean Pearson correlation for 38 nutrient intakes was 0.65 (range, 0.50-0.77), and the mean Spearman rank correlation for food intakes was 0.60 (range, 0.37-0.77). Current adult diet was only weakly correlated with recalled adolescent diet (for nutrient intakes, mean r = 0.20). For assessment of validity, 272 mothers of the NHSII participants were asked to report information on their daughters' adolescent diets using the HS-FFQ. In this comparison, the mean Pearson correlation was 0.40 (range, 0.13-0.59) for nutrients, and the mean Spearman rank correlation for foods was 0.30 (range, 0.10-0.61). While further studies are warranted, these findings imply that this food frequency questionnaire provides a reasonable record of adolescent diet.     

Nutrient intake and food consumption among pregnant women from an agricultural region of Morocco

This study aimed to assess dietary intake and nutrient adequacy in pregnant women selected from an agricultural region of Morocco. On a sample of 172 pregnant women from rural and urban area, data on socio-demographic characteristics and dietary habits by a quantified food frequency were collected using questionnaires. Mean daily intakes of energy and nutrients were estimated and compared to reference nutrient intakes (RNI).

The results show that the mean daily intakes of energy (3110.9?kcal in urban; 2707.5?kcal in rural) and some nutrients were adequate. However, iron, folate, zinc and calcium intakes were inadequate for the majority of women and more markedly in rural area. Education level appeared to affect nutrient intakes while no differences were registered across pregnancy stages or according to household size. The study suggests that an education program should be conducted to improve dietary intakes in order to prevent risks for pregnancy outcome in this population.     

Associations between maternal concern for healthful eating and maternal eating behaviors, home food availability, and adolescent eating behaviors

OBJECTIVE: Evaluate the relationship between maternal concern for healthful eating and maternal and adolescent dietary intake, eating behavior, and home food environment. DESIGN: Mothers of a subsample of adolescents who participated in a school-based survey (Project Eating Among Teens [EAT]) completed telephone interviews. PARTICIPANTS: Seven hundred fourteen mother-adolescent pairs. VARIABLES MEASURED: Mothers responded to a question regarding how much they are personally concerned with eating healthfully, and adolescents responded to a question regarding perceptions of their mothers' concern about eating healthfully. Dependent variables included adolescent and parent food intake and home food environment. ANALYSIS: Multinomial cumulative logistic regression models, adjusted for maternal race/ethnicity, socioeconomic status (SES), and adolescent grade level. RESULTS: A positive association was found between maternal concern for healthful eating and maternal fruit and vegetable intake, maternal breakfast and lunch consumption, and serving fruits and vegetables in the home. Maternal concern for healthful eating (as reported by mothers) was not associated with adolescent behavior. Adolescent perception of maternal concern for healthful eating was positively associated with adolescent fruit and vegetable intake. CONCLUSIONS AND IMPLICATIONS: Mother's concern for healthful eating is associated with maternal eating behavior and the home food environment. Adolescent perceptions of maternal attitudes are a stronger predictor than actual maternal attitudes of adolescent behavior. Parents should be encouraged to share their beliefs regarding the importance of healthful eating with their adolescents.     

Older pregnant women and adolescents: nutrition data after enrollment in WIC

Although there has been an increase in pregnancy in women over 35 years of age, the literature contains no information on dietary intakes of older pregnant women. Several studies have reported the nutritional status of pregnant adolescents who are considered to be at nutritional risk. This study investigated the energy, nutrient, and food intake patterns of 63 low-income pregnant women over 35 compared with 526 pregnant adolescents. Nutrient intake was assessed using a standardized 24-hour dietary recall protocol. Energy values for both groups were below recommended levels, and neither group gained the recommended amount of weight. Obesity may have been the reason for the lack of weight gain by the older pregnant women, since more than 50% of the older pregnant women were calculated to be obese prior to pregnancy. The younger women reported consuming less milk but more snack foods with lower nutrient densities, which significantly increased their energy values over those of the older group. In comparison with diets reported in other studies, the diets of the older pregnant women were more nutrient dense for most nutrients. Although all participants were enrolled in WIC, an equal number of women from both groups stated that they did not have the supplemental foods in their households at the time of interview.     

Evaluation of energy, nutrient and dietary fiber intakes of adolescent males

OBJECTIVE: The minimal data available on the current energy, nutrient and dietary fiber intakes of adolescent males challenges the development of effective nutrition education programs. There is a need for research into the current intakes of adolescent males and in particular their relation to the current Dietary Reference Intakes (DRIs). The primary objective of this study was to assess the diet of adolescent males and relate energy, nutrient and dietary fiber intakes to the DRIs. Secondary objectives were to relate energy, macronutrient and dietary fiber intakes to body mass index (BMI)-for-age percentile categories as well as to explore vitamin/mineral supplement use and soft drink consumption. METHODS: Three-day food records were completed by 180 healthy adolescent males for analysis of energy, nutrient and dietary fiber intakes from food and supplements. Following adjustment for intra-individual variability, nutrient intake percentile distributions were related to the DRIs. Energy, macronutrient and dietary fiber intakes were compared among BMI-for-age percentile categories and diets were evaluated for vitamin/mineral supplement use and soft drink consumption. RESULTS: Median intakes for percent energy from carbohydrate, fat and protein were within the Accepted Macronutrient Distribution Ranges. Intakes of micronutrients with Estimated Average Requirement values indicated that greater than 50% of subjects consumed inadequate amounts of vitamin A and vitamin B6, and greater than 75% of subjects consumed inadequate amounts of magnesium, phosphorus and zinc. Subjects classified as overweight had significantly lower energy and carbohydrate intakes compared with subjects classified as having an acceptable body weight. The prevalence of vitamin/mineral supplement use was 16.1% and 67% of subjects reported daily consumption of soft drinks. CONCLUSION: Results of this study reveal that adolescent males are consuming the recommended amounts of macronutrients but may be at risk for consuming inadequate levels of specific micronutrients. Nutrition education programs should consider targeting select micronutrients to improve nutritional intakes of adolescent males.     

Validity and Reproducibility of a Food Frequency Questionnaire to Assess Nutrients Intake of Pregnant Women in the South-East of Spain

Proper nutrition during pregnancy is pivotal to maintain good health for the child and the mother. This study evaluates the reproducibility and validity of a food frequency questionnaire (FFQ) designed to assess nutrient intake during pregnancy in the GENEIDA (Genetics, Early life Environmental Exposures and Infant Development in Andalusia) prospective birth cohort study. In addition, the nutrient intake was estimated and then compared with European guidelines and other studies. Diet information was collected from 690 pregnant women using a FFQ administered at two periods of pregnancy (used for the reproducibility study) and 24-h dietary recall (for the validity study). Statistical approaches included Spearman’s correlation coefficient and percentage agreement, classifying women into the same or adjacent quintiles to assess reproducibility, and limits of agreement (LoA) to evaluate validity. In the study of reproducibility, significant correlations for nutrients adjusted for total energy had an average of 0.417. Moreover, the percentage of subjects classified in the same quintile for nutrient intakes were above 66%. In the validation study, the significant correlation for nutrients adjusted for total energy had an average of 0.272. Nevertheless, the percentage of results in the LoA was above 94%. Our results were similar to other studies suggesting that the FFQ used is a valid tool of collect dietary intakes for South-East Spanish pregnant women.     

Impact of dietary counselling on nutrient intake during pregnancy: a prospective cohort study

The aim of this study was to assess the impact of dietary counselling combined with the provision of food products on food and nutrient intake in pregnant women. We carried out a prospective cohort study of healthy and atopic pregnant women (n 209), who were randomized into dietary intervention and control groups. The intervention group received dietary counselling and food products to modify the fat composition of their diet to meet current recommendations. Three-day food records were collected during each trimester of pregnancy. Women in the intervention group consumed more vegetables, fruits, soft margarines and vegetable oils and less butter than those in the control group during the course of pregnancy (P<0.05). The main distinction between the groups in nutrient intake over the pregnancy was attributable to a higher energy intake (% energy) of PUFA by 0.5%energy (95% CI 0.1, 0.8) and to a lower intake of SFA by 0.8 % energy (95% CI -1.4, -0.4) in the intervention group. Dietary intake of vitamin E was 1.4 mg (95% CI 0.6, 2.2), folate 20.9 microg (95% CI 0.8, 41.0) and ascorbic acid 19.8 mg (95 % CI 3.5, 36.0) higher in the intervention group compared to the controls, while no differences in other nutrients were detected. Dietary counselling combined with the provision of food products during pregnancy is of importance in modifying food and nutrient intake, with potential health benefits.     

Nutrient intake among female shift workers in a computer factory in Japan

Based on a 4-day questionnaire survey for all meals and snacks consumed by female workers in a computer factory in Japan, consisting of 44 daytime workers and 93 weekly-rotating shift workers (of whom 47 and 46 were engaged in, respectively, early-shift work and late-shift work during the survey week), the present study aimed to clarify the effects of shift work on their nutrient intakes in association with food consumption patterns. Their dietary intakes for 3 working days and an off day were assessed by self-registered food consumption records with the aid of a photographic method, and intakes of energy, protein, fat, carbohydrate, calcium and iron were estimated. The inter-group differences were prominent in the working days. The shift workers, particularly the late-shift workers, took smaller amounts of energy and nutrients than the daytime workers, implying that the former group's nutritional status has been worsened, judged from the recommended dietary allowance for Japanese. Their inadequate nutrient intake was due to lower meal frequency and poor meal quality, both of which were conditioned by shift work.     

Nutrient intake among female shift workers in a computer factory in Japan

Based on a 4-day questionnaire survey for all meals and snacks consumed by female workers in a computer factory in Japan, consisting of 44 daytime workers and 93 weekly-rotating shift workers (of whom 47 and 46 were engaged in, respectively, early-shift work and late-shift work during the survey week), the present study aimed to clarify the effects of shift work on their nutrient intakes in association with food consumption patterns. Their dietary intakes for 3 working days and an off day were assessed by self-registered food consumption records with the aid of a photographic method, and intakes of energy, protein, fat, carbohydrate, calcium and iron were estimated. The inter-group differences were prominent in the working days. The shift workers, particularly the late-shift workers, took smaller amounts of energy and nutrients than the daytime workers, implying that the former group's nutritional status has been worsened, judged from the recommended dietary allowance for Japanese. Their inadequate nutrient intake was due to lower meal frequency and poor meal quality, both of which were conditioned by shift work.     

Differences in reported winter and summer dietary intakes in young adults in Spain

Representative data of usual food consumption are necessary in order to establish accurate conclusions on the relationship between diet and disease. In most studies data are collected at one particular time of the year. The aim of this study was to determine the influence of season of the year on dietary intake estimates. Three hundred and three people aged 19-40 years from northwest Spain recorded their intake twice (in winter and summer) using the seven non-consecutive-day dietary record method. A total of 247 foods (arranged into 16 major food groups) and 27 nutrients were determined. Most fruits and vegetables, as well as some milk products showed significant seasonal differences. Daily total food consumption amount (g) was higher in winter than summer in males. Higher average intakes of energy (men) and a large number of nutrients (both sexes) were observed in winter. This seasonal influence on dietary intake estimates implies significant differences in fractions of Spanish recommendations covered (lower in summer) for energy (men) and most nutrients (both sexes). As expressed in amount/MJ (densities), most nutrients showed higher values in winter in women. Data in our study suggest that the substantial variations of nutrient intakes throughout the course of the year mainly depend on food (energy) amount variations (quantitative diet changes) in males, while changes in densities of nutrients (qualitative diet changes) are mainly responsible for dietary variations in females. Results in the present study suggest that considering the season of the year it will enhance the results of dietary surveys and ensure the accuracy of studies that link diet with disease.     

Differences in reported winter and summer dietary intakes in young adults in Spain

Representative data of usual food consumption are necessary in order to establish accurate conclusions on the relationship between diet and disease. In most studies data are collected at one particular time of the year. The aim of this study was to determine the influence of season of the year on dietary intake estimates. Three hundred and three people aged 19–40 years from northwest Spain recorded their intake twice (in winter and summer) using the seven non-consecutive-day dietary record method. A total of 247 foods (arranged into 16 major food groups) and 27 nutrients were determined. Most fruits and vegetables, as well as some milk products showed significant seasonal differences. Daily total food consumption amount (g) was higher in winter than summer in males. Higher average intakes of energy (men) and a large number of nutrients (both sexes) were observed in winter. This seasonal influence on dietary intake estimates implies significant differences in fractions of Spanish recommendations covered (lower in summer) for energy (men) and most nutrients (both sexes). As expressed in amount/MJ (densities), most nutrients showed higher values in winter in women. Data in our study suggest that the substantial variations of nutrient intakes throughout the course of the year mainly depend on food (energy) amount variations (quantitative diet changes) in males, while changes in densities of nutrients (qualitative diet changes) are mainly responsible for dietary variations in females. Results in the present study suggest that considering the season of the year it will enhance the results of dietary surveys and ensure the accuracy of studies that link diet with disease.     

The distribution of energy and nutrient intakes within households

The assessment of dietary adequacy, using data from household food surveys, relies on the assumption that intakes of energy and nutrients are distributed within households in the same pattern as the recommended levels against which adequacy is being assessed. That this assumption is probably ill-founded has been demonstrated by Nelson (1986). However, very little information is available on the actual distributions of dietary intake within households because dietary surveys usually cover either the household as a single unit or only a single member of each household. As part of a larger study, 73 individuals within 23 households all provided information using the 24-h dietary recall technique. This data has been analysed using the method described by Nelson (1986) and the Fesults lend further support to the suggestion that the interpretation of dietary adequacy in household food surveys should take into account the distribution of nutrient intakes within the households.     

Sensitivity of Food-Based Recommendations Developed Using Linear Programming to Model Input Data in Young Kenyan Children

Food-based recommendations (FBR) developed using linear programming generally use dietary intake and energy and nutrient requirement data. It is still unknown to what extent the availability and selection of these data affect the developed FBR and identified problem nutrients. We used 24 h dietary recalls of 62 Kenyan children (4–6 years of age) to analyse the sensitivity of the FBR and problem nutrients to (1) dietary intake data, (2) selection criteria applied to these data and (3) energy and nutrient requirement data, using linear programming (Optifood©), by comparing a reference scenario with eight alternative scenarios. Replacing reported by estimated consumption frequencies increased the recommended frequencies in the FBR for most food groups while folate was no longer identified as a problem nutrient. Using the 10–90th instead of the 5–95th percentile of distribution to define minimum and maximum frequencies/week decreased the recommended frequencies in the FBR and doubled the number of problem nutrients. Other alternative scenarios negligibly affected the FBR and identified problem nutrients. Our study shows the importance of consumption frequencies for developing FBR and identifying problem nutrients by linear programming. We recommend that reported consumption frequencies and the 5–95th percentiles of distribution of reported frequencies be used to define the minimum and maximum frequencies.     

Dietary patterns among postpartum women treated at a municipal health center in Rio de Janeiro, Brazil

This study aimed to longitudinally compare nutrient and food intakes by 276 lactating women. Dietary intake was collected using a food frequency questionnaire. Data analysis used the Student-t and ANOVA tests, comparing quantitative and qualitative dietary variation from pregnancy to postpartum. Mean daily energy intake was 2,889 kcal for pregnant and 2,081 kcal for lactating women. Macronutrient dietary distributions were within internationally recommended standards. Compared to pregnancy, there was a decrease in most nutrients and foods ingested during postpartum. Dietary changes increased the density of proteins, fat, iron, rice, beans, chicken, and beef (p < 0.02) and decreased the density of carbohydrate, cereals, fruits, and milk and dairy products (p < 0.001). The results indicate a need for dietary guidelines for women, particularly during the postpartum period.