Validation of a food frequency questionnaire to assess food group intake by pregnant women

Assessing the reproducibility and validity of a food frequency questionnaire for pregnant women from the Chinese Miao ethnic group

Background

Currently, no food frequency questionnaire is available to be administered exclusively to ethnic minorities in China. This study aimed to evaluate the reproducibility and validity of a culturally tailored semi-quantitative food frequency questionnaire (FFQ) designed for pregnant women belonging to the Miao ethnic group in China.

Methods

A total of 74 questions in the FFQ were administered to collect dietary information from Miao women in China during their pregnancy. This study included 153 and 127 pregnant women, respectively, for testing the validity and reproducibility of the results. Baseline FFQ data (FFQ1) were collected initially, followed by the administration of a repeated FFQ 4-6 weeks later (FFQ2). Two 24-h recalls (24HR) were used as references to compare food groups and nutrient intake. Pearson/Spearman's coefficients were used to measure the validity and reproducibility of the FFQ. Quartile cross-classification, weighted kappa coefficients, and Bland-Altman plots were employed to assess the agreement.

Results

Most food groups and nutrient intake estimated by the FFQ were higher than those estimated by the 24HR. Food groups and nutrients' correlations for FFQ vs. 24HR after being energy-adjusted and de-attenuated, respectively, were 0.10 (vegetables) to 0.45 (grains/tubers) and 0.15 (iron) to 0.52 (riboflavin). Comparatively, correlation coefficients for FFQ1 vs. FFQ2 ranged from 0.41 (fruit) to 0.71 (vegetables) and from 0.45 (energy) to 0.64 (calcium). The percentage of pregnant women classified in the same or adjacent quartiles ranged from 64.08% (vegetables) to 95.29% (sour soup) and from 68.88% (vitamin E) to 78.81% (energy). Weighted kappa coefficients exceeded 0.2 for food groups and most nutrients, and Bland-Altman plots demonstrated acceptable agreement between the two tools.

Conclusions

This study provides novel information on the validation of FFQ. It demonstrates that the FFQ exhibits ideal reproducibility and acceptable validity in estimating and ranking the intake of food groups and most nutrients among pregnant women belonging to the Chinese Miao ethnic group.

Validity and Reproducibility of a Semiquantitative Food Frequency Questionnaire for Measuring Intakes of Foods and Food Groups

We evaluated the validity and reproducibility of a semiquantitative food frequency questionnaire (FFQ) for measuring intakes of 149 foods and 25 food groups among 736 participants of the Women's Lifestyle Validation Study (WLVS, 2010-2012) and 649 participants of the Men's Lifestyle Validation Study (MLVS, 2011-2013). Validity of the FFQ compared with two 7-day dietary records measured 6 months apart and the reproducibility between 2 FFQs administered 1 year apart (FFQ1 and FFQ2) were assessed using Spearman correlations and intraclass correlation coefficients. The average 1-year reproducibility of FFQ-measured foods was 0.64 in both the WLVS and MLVS. Reproducibility of the food groups (mean = 0.71 among women and 0.72 among men) was generally higher than that for individual foods. Among women, the average validity correlation for individual foods was 0.59 when comparing FFQ2 with the 7-day dietary records. Among men, the corresponding average validity correlation was 0.61. Compared with individual foods, food groups had slightly higher validity correlations in both women (range, 0.45-0.92; mean = 0.61) and men (range, 0.46-0.88; mean = 0.65). This study reaffirms that the FFQ performs well in measuring most foods and food groups and provides data to adjust for measurement errors in epidemiologic studies of foods and food groups.

Association between persistent organic pollutants in human milk and the infant growth and development throughout the first year postpartum in a cohort from Rio de Janeiro, Brazil

Persistent organic pollutants (POPs) are compounds that are recalcitrant and ubiquitous that bioaccumulate in human milk (HM) and can impact infant growth and development. We explore the association between POP concentration in HM at 2-50 days postpartum and infant growth and development trajectory throughout the first year of life. A cohort of 68 healthy adult Brazilian women and their infants were followed from 28 to 35 gestational weeks to 12 months postpartum. HM samples were collected between 2 and 50 days postpartum, and POP concentrations were analyzed using gas chromatography with mass spectrometry. Concentrations of POPs >limit of quantification (LOQ) were defined as presence, and concentrations ≤LOQ as an absence. Growth z-scores were analyzed according to WHO growth charts and infant development scores according to Age & Stages Questionnaires at 1 (n = 66), 6 (n = 50), and 12 months (n = 45). Linear mixed effects (LME) models were used to investigate the association of POPs in HM with infant growth and development. Benjamini-Hochberg (BH) correction for multiple testing was performed to reduce the false discovery ratio. P < 0.1 was considered for models with the interaction between POPs and time/sex. After BH correction, adjusted LME models with time interaction showed (1) a positive association between the presence of β hexachlorocyclohexane and an increase in head circumference-for-age z-score (β = 0.003, P = 0.095); (2) negative associations between total POPs (β = -0.000002, P = 0.10), total organochlorine pesticides (β = -0.000002, P = 0.10), and dichlorodiphenyldichloroethylene concentrations in HM (β = -0.000002, P = 0.10) and fine motor scores. No statistical difference between the sexes was observed. Postnatal exposure to organochlorine pesticides in HM shows a positive association with the trajectory of head circumference-for-age z-score and a negative association with the trajectories of fine motor skills scores. Future studies on POP variation in HM at different postpartum times and their effect on infant growth and development should be encouraged.

Association of pre-pregnancy maternal overweight/obesity and dietary intake during pregnancy with the concentrations of persistent organic pollutants in the human milk of women from Rio de Janeiro, Brazil

Persistent organic pollutants (POPs) are toxic chemical compounds that can bioaccumulate, adhere to lipid matrices, and affect human health. This study aimed to investigate the association between maternal pre-pregnancy overweight/obesity and dietary intake during pregnancy and POP concentrations in the human milk of women from Rio de Janeiro, Brazil. One hundred and forty-seven women were followed from the third trimester of pregnancy until 119 days postpartum, and 77 human milk samples were analyzed between 2 and 119 days postpartum. POP concentrations were analyzed using gas chromatography-triple quadrupole mass spectrometry. Pregnancy dietary intake was estimated using a semi-quantitative food frequency questionnaire, and pre-pregnancy body mass index at baseline was classified as normal or overweight/obesity. Multiple logistic and linear regression models were performed to investigate the association between pre-pregnancy overweight/obesity, dietary intake during pregnancy, and POP concentrations in human milk. The models were adjusted for maternal age, maternal schooling, total cholesterol serum concentrations, and time postpartum. The analyses were corrected for multiple comparisons using the Benjamini-Hochberg test. Significant associations were observed between pre-pregnancy overweight/obesity and dichlorodiphenyldichloroethane (ppDDE), polychlorinated biphenyl (PCB)74, PCB138, PCB153, PCB170, PCB180, total PCBs, total 4PCBs, total 2 organochlorine pesticides (OCPs), and total POP concentrations. Higher daily lipid intake during pregnancy increased human milk hexachlorobenzene (HCB). This study showed that pre-pregnancy overweight/obesity and total lipid intake during pregnancy were associated with POP concentrations in the milk of women from Rio de Janeiro, Brazil. To promote adequate nutritional status since preconception and surveillance and control of POP in the environment could be essential to ensure binomial mother-infant health and biomonitoring studies and programs for these POPs should be stimulated.

Development and Validation of a Food Frequency Questionnaire for Evaluating the Nutritional Status of Patients with Cancer

Patients with cancer need to maintain proper nutritional status to overcome cancer, alleviate the side effects of chemotherapy, and prevent a recurrence. As such, it is necessary to manage nutritional status. This study aimed to develop a dish-based semi-quantitative food frequency questionnaire (FFQ) to evaluate the nutritional status of patients with cancer and assess the validity of the FFQ. A total of 109 dish items were selected through contribution and variability analyses using the 2016-2018 Korea National Health and Nutrition Examination Survey data. The FFQ was validated against the average 3-day dietary records of 100 patients with cancer. Pearson correlation coefficients and quartile agreements between FFQ and 3-day dietary records were calculated for intake of energy, macronutrients, and micronutrients. Age and energy-adjusted Pearson correlation coefficients ranged from 0.20 (iron) to 0.54 (potassium). The percentage of participants who were classified into the same or adjacent quartile between the FFQ and the 3-day dietary record ranged from 68% (protein) to 81% (energy, dietary fiber). The results suggest that the FFQ is an appropriate tool for assessing nutritional status in Korean cancer patients.

Prepregnancy Body Mass Index and Lipoprotein Fractions are Associated with Changes in Women's Serum Metabolome from Late Pregnancy to the First Months of Postpartum

BACKGROUND

Pregnancy and postpartum are periods of intense changes in women's metabolism. The knowledge of the metabolites and maternal factors underlying these changes is limited.

OBJECTIVES

We aimed to investigate the maternal factors that could influence serum metabolome changes from late pregnancy to the first months of postpartum.

METHODS

Sixty-eight healthy women from a Brazilian prospective cohort were included. Maternal blood and general characteristics were collected during pregnancy (28-35 wk) and postpartum (27-45 d). A targeted metabolomics approach was applied to quantify 132 serum metabolites, including amino acids, biogenic amines, acylcarnitines, lysophosphatidylcholines (LPC), diacyl phosphatidylcholines (PC), alkyl:acyl phosphatidylcholines (PC-O), sphingomyelins with (SM) and without hydroxylation [SM(OH)], and hexoses. Metabolome changes from pregnancy to postpartum were measured as log₂ fold change (log₂FC), and simple linear regressions were employed to evaluate associations between maternal variables and metabolite log₂FC. Multiple comparison-adjusted P values of < 0.05 were considered significant.

RESULTS

Of 132 metabolites quantified in serum, 90 changed from pregnancy to postpartum. Most metabolites belonging to PC and PC-O classes decreased, whereas most LPC, acylcarnitines, biogenic amines, and a few amino acids increased in postpartum. Maternal prepregnancy body mass index (ppBMI) showed positive associations with leucine and proline. A clear opposite change pattern was observed for most metabolites across ppBMI categories. Few phosphatidylcholines were decreased in women with normal ppBMI, while an increase was observed in women with obesity. Similarly, women with high postpartum levels of total cholesterol, LDL cholesterol, and non-HDL cholesterol showed increased sphingomyelins, whereas a decrease was observed for women with lower levels of those lipoproteins.

CONCLUSIONS

The results revealed several maternal serum metabolomic changes from pregnancy to postpartum, and the maternal ppBMI and plasma lipoproteins were associated with these changes. We highlight the importance of the nutritional care of women prepregnancy to improve their metabolic risk profile.

Factors associated with longitudinal changes in B-vitamin and choline concentrations of human milk

BACKGROUND

Little is known regarding the associations between maternal factors and B-vitamin and choline concentrations in early milk and the trajectories of these vitamins during lactation.

OBJECTIVES

In this hypothesis-generating study, we modeled the association between maternal and offspring factors and longitudinal changes in milk B-vitamin and choline concentrations throughout lactation.

METHODS

A hundred women were studied in a prospective birth cohort and milk samples from 52 women were collected at 2-8 d, 76 women at 28-50 d, and 42 women at 88-119 d postpartum. Maternal dietary intake during pregnancy and lactation was assessed by an FFQ. Linear mixed-effects models with interaction terms were used to evaluate changes in milk B-vitamin and choline concentrations over time based on maternal factors and the early postpartum concentrations of these micronutrients.

RESULTS

The women with higher early postpartum milk concentrations of niacin (βinteraction = -0.02; SE = 0.00; P < 0.001), pantothenic acid (βinteraction = -0.10; SE = 2.56; P < 0.001), vitamin B-12 (βinteraction= -0.10; SE = 0.03; P < 0.001), and choline (βinteraction= -0.90; SE = 0.18; P < 0.001) exhibited a decrease in their concentrations throughout lactation. The participants with overweight and obesity prepregnancy experienced an increase in milk vitamin B-12 concentrations over time (βinteraction = 0.04; SE = 0.02; P = 0.06). In contrast, a decrease in vitamin B-12 concentration was observed among women with vitamin B-12 intake below the RDA during pregnancy (βinteraction= -0.08; SE = 0.05; P = 0.07). The women with niacin intake below the RDA during lactation experienced an increase in milk concentrations over time (βinteraction = 0.01; SE = 0.01; P = 0.03). A gestational age at birth >40 wk was associated with an increase in milk choline concentration throughout lactation (βinteraction = 0.54; SE = 0.16; P< 0.01).

CONCLUSIONS

Changes in B-vitamin and choline concentrations in human milk over time may be associated with the early concentrations of these micronutrients in milk, maternal prepregnancy BMI, dietary intake, and gestational age at delivery.

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.

Relationship between the quality of the pregnant woman's diet and birth weight: a prospective cohort study

BACKGROUND

Birth weight is a relevant predictor of childhood health outcomes. Studies investigating the association between modifiable risk factors, as the maternal diet quality, and birth weight are needed. We aimed to investigate the association between the Diet Quality Index Adapted for Pregnant Women (IQDAG) score and birth weight.

METHODS

This is a prospective cohort that includes 547 Brazilian mother-child pairs. Dietary recalls and a food frequency questionnaire were obtained during pregnancy. Information on birth weight, sex, and gestation duration were obtained from the Live Birth Information System (SINASC).

RESULTS

On total, 3.8% of the newborns were classified as low birth weight (LBW), 6.0% with macrosomia, 10.2% small for gestational age (SGA), and 11.2% large for gestational age (LGA). The mean (SD) IQDAG score was 70.1 (11.8). Adjusted logistic regression models showed that women in the third tertile of the IQDAG score presented a lower risk of having LGA babies [OR 0.44 (95% CI 0.22, 0.90), p-trend = 0.02] compared to the first tertile. Women in the third tertile of omega-3 intake presented a lower risk of giving birth to LGA infants [OR 0.33 (95% CI 0.15, 0.69), p-trend = 0.00] and LBW infants [OR 0.18 (95% CI 0.04, 0.83), p-trend = 0.02] when compared to the first tertile. There was also a lower SGA trend among the children of women in the third tertile of omega-3 intake [OR 0.43 (95% CI 0.17, 1.07), p-trend = 0.03] compared to the first tertile.

CONCLUSION

A better diet quality and higher omega-3 intake are protective factors for LGA babies, and increased maternal omega-3 intake reduce the risk of LBW and LGA, and may be a protective factor against the birth of SGA infants.

Validation and reproducibility of a FFQ focused on pregnant women living in Northeastern Brazil

OBJECTIVE

The aim of the current study is to assess the validity and reproducibility of a FFQ focused on pregnant women living in Northeastern Brazil.

DESIGN

Three 24-hour-dietary recalls (24 hR) and two FFQ were applied at 15-d intervals between research stages in order to confirm the validity and reproducibility of the FFQ. Validity assessment was based on Pearson's correlation coefficient (PCC) or Spearman's correlation coefficient (SCC) between FFQ and the mean of three 24 hR (the 24 hR was used as reference standard), whereas reproducibility assessment was based on the intraclass correlation coefficient (ICC) among FFQ, and P < 0·05 was set as significance level.

SETTING

Public health network of a capital city in Northeastern Brazil.

PARTICIPANTS

Overall, 100 pregnant women were included in the study.

RESULTS

The PCC or SCC adopted in the validity analysis recorded the recommended values (from 0·4 and 0·7) for energy (0·44; P < 0·001), carbohydrate (0·40; P < 0·001), vitamins B2 (0·40; P < 0·001), B5 (0·40; P < 0·001), E (0·47; P < 0·001), B12 (0·48; P < 0·001), phosphorus (0·92; P < 0·001), Mg (0·81; P < 0·001), Se (0·70; P < 0·001), cholesterol (0·64; P < 0·001), saturated (0·76; P < 0·001), polyunsaturated (0·73; P < 0·001) and monounsaturated fats (0·87; P < 0·001) and fibres (0·77; P < 0·001). Mg (0·72; P < 0·001), Fe (0·65; P < 0·001), lipid (0·56; P < 0·001) and energy (0·55; P < 0·001) presented ICC within the recommended reproducibility values.

CONCLUSIONS

The FFQ developed in the current study is a useful tool to assess the usual food intake of pregnant women.

The association of dietary glycaemic index and glycaemic load with gestational weight gain and newborn birth weight

Diet during pregnancy is related to several maternal and infant health outcomes; however, the relationship between maternal dietary glycaemic index (GI) and glycaemic load (GL) and gestational weight gain (GWG) or newborn birth weight is controversial. The purpose of the present study was to investigate the relationship between maternal dietary GI and GL and GWG and birth weight. A cohort of adult pregnant women with usual obstetric risk was followed in Botucatu, SP, Brazil. Two 24-h dietary recalls were collected in each gestational trimester (<14, 24-27, 31-34 weeks), one in person and the other by telephone. GI and GL were determined using the software Nutrition Data System for Research. GWG was obtained from medical records and evaluated as the weekly GWG between the second and third gestational trimesters. Newborn birth weight z-score in relation to gestational age was evaluated according to Intergrowth-21st Project recommendations. A multiple linear regression model, adjusted for potential confounders, showed a one-point increase in the GI resulted in a mean decrease of 12·9 (95 % CI -21·48, -4·24) g in weekly GWG; GL was not associated with this outcome. The birth weight z-score was not associated with GI (P = 0·763) or GL (P = 0·317). In conclusion, in a cohort of pregnant women considered at usual risk for obstetric complications, maternal dietary GI was negatively associated with weekly GWG in the second and third gestational trimesters. No association was observed between GL and GWG, and neither GI nor GL was associated with birth weight z-score.

Association between the Diet Quality Index Adapted for Pregnant Women (IQDAG) and excess maternal body weight

Abstract Objectives: to investigate the relationship between the Diet Quality Index Adapted for Pregnant Women (IQDAG) and excess maternal body weight. Methods: a cross-sectional study was conducted with 754 adult pregnant women, in Ribeirão Preto, São Paulo, between 2011 and 2012. The criteria proposed by Atalah were used to classify the body mass index (BMI). Adjusted multinomial logistic regression models were employed to investigate the relationship between the IQDAG and being overweight and obese, estimating the odds ratio (OR) and the 95% confidence interval (CI95%). Results: the mean (SD) age of women was 28 (5) years, 33.4% were overweight and 25.6% obese. The pregnant women with higher scores in the IQDAG were less likely to be overweight [OR= 0.56 (CI95% = 0.37-0.85)] or obese [0.43 (0.26-0.71)]; those with higher scores in the "Fiber" [0.51 (0.33; 0.78)] and "Iron" [0.62 (0.40-0.96)] components were less likely to be overweight. However, women with higher scores in the percentage of energy from ultra-processed foods were more likely to be overweight [1.72 (1.10-2.94)] or obese [5.24 (2.80-9.80)], when compared to women with lower scores. Conclusions: poorer quality maternal diets were observed among the women who were overweight and obese during pregnancy.

Hábitos alimentares das gestantes brasileiras:revisão integrativa da literatura

Resumo Os hábitos alimentares das mulheres grávidas são influenciados por diversos fatores, sendo essencial conhecê-los para poder realizar intervenções nutricionais na atenção pré-natal. O objetivo desta revisão integrativa foi analisar a produção bibliográfica sobre hábitos alimentares de gestantes brasileiras. Foram buscados artigos na Biblioteca Virtual em Saúde (BVS), PubMed, Scopus, Web of Science e na Scientific Eletronic Library Online (SciELO) utilizando os seguintes descritores: “Gestantes” OR “Grávidas” AND “Hábitos Alimentares” e os termos “Pregnant women” AND “Food habits” AND “Brazil” para busca em inglês. Após a adoção dos critérios de inclusão e exclusão foram analisados 18 estudos. Alguns estudos contemplaram populações específicas como adolescentes ou gestantes não obesas. O instrumento mais utilizado para investigação do consumo alimentar de gestantes foi o Questionário de Frequência Alimentar. A maioria mostrou que a dieta das gestantes precisa de melhorias, especialmente pelo baixo consumo de frutas, verduras e hortaliças, elevado consumo de açúcares, doces e gorduras. A maioria dos estudos concluiu e reforçou a importância e a necessidade da educação nutricional pelos profissionais atuantes no pré-natal. Mais estudos são necessários para compreensão mais acurada destes hábitos alimentares.

Relative Validity and Reproducibility of a Food Frequency Questionnaire to Assess Food Group Intake in Pregnant Jordanian Women

BACKGROUND

Research on the relationship between maternal diet and pregnancy outcomes requires valid dietary assessment tools in pregnancy.

OBJECTIVE

This study aimed to develop and examine the relative validity and reproducibility of a quantitative food frequency questionnaire (FFQ) to estimate food group intake in a sample of pregnant Jordanian women.

DESIGN

In this validation study, food group intake from a culturally sensitive quantitative FFQ was compared with food group intake from three 24-hour dietary recalls.

PARTICIPANTS AND SETTING

The validation study was conducted from 2015 to 2017 at the maternity clinics in Jordan University Hospital among 131 healthy singleton pregnant Jordanian women. Of these women, 30 also took part in the reproducibility phase, which involved repeated completion of the FFQ in a time frame of 1 month. Pregnant women who had gestational diabetes, preeclampsia, and chronic diseases were excluded.

MAIN OUTCOME MEASURES

Relative validity and reproducibility of a 117-item quantitative FFQ used to estimate usual food intake over a period of 1 month.

STATISTICAL ANALYSES PERFORMED

Intraclass correlation coefficients and weighted κ statistics were calculated to test the reproducibility between the two administrations of the FFQ. Pearson correlations were estimated to validate the FFQ against 24-hour dietary recalls. Cross-classification and Bland-Altman plots were used to examine the agreement between the two dietary assessment methods.

RESULTS

The intraclass correlation coefficients between the two FFQs ranged from 0.24 for legumes to 0.93 for processed meats. A moderate level of agreement was observed between two FFQs. De-attenuated and energy-adjusted correlations ranged from 0.08 for sweets and sugar to 0.93 for sugary drinks. On average, 50.9% and 45.2% of participants were classified by the FFQ and the 24-hour dietary recalls into the same quartile based on their crude and energy-adjusted food group intake, respectively. Bland-Altman plots showed satisfactory agreement between two methods for most food groups.

CONCLUSIONS

The FFQ showed moderate reproducibility and good relative validity for most food groups.

Development of a Diet Quality Index Adapted for Pregnant Women

OBJECTIVE:

To develop a Diet Quality Index Adapted for Pregnant Women (IQDAG) and to evaluate its relation with the characteristics of women treated at the Brazilian Unified Health System.

METHODS:

The data on food intake come from a cross-sectional study carried out with 785 adult pregnant women in the city of Ribeirão Preto, state of São Paulo, Brazil, between 2011 and 2012. The index was based on the recommendations of the Brazilian Ministry of Health, previous national dietary indexes, and the new Dietary Guidelines for the Brazilian Population. We used the ANOVA, Kruskal-Wallis, and chi-square tests to describe the quality of the diet according to the characteristics of the mother.

RESULTS:

The IQDAG has nine components, and it is represented by three food groups (in servings/1,000 kcal), five nutrients, and a moderator component. A high proportion of pregnant women reached the maximum score for the components of legumes and vegetables. However, few women reached the maximum score for consumption of fresh fruits, fiber, omega-3, calcium, folate, iron, and ultra-processed foods. We verified a better quality of diet among older and eutrophic pregnant women who reported practicing more physical activity and taking dietary supplements. We also observed the highest index score among women with higher intake of carbohydrates, proteins, vitamins C, E, and A, and minerals calcium, folate, and iron, as well as among those with lower intake of total fats and saturated fats.

CONCLUSIONS:

This dietary index is unprecedented in incorporating the recommendation of the new Dietary Guidelines for the Brazilian Population regarding the moderation of the consumption of ultra-processed foods. It was useful in evaluating the quality of the diet of pregnant women and we verified a higher score among older and eutrophic women who reported a healthy lifestyle. Strategies are needed to promote a higher consumption of fresh fruits, foods high in fiber, omega-3, calcium, folate, iron, and minimally processed foods in pregnant women.

Validity of an FFQ to measure nutrient and food intakes in Tanzania

OBJECTIVE

FFQ are often used to estimate food and nutrient intakes to rank individuals by their level of intake. We evaluated the relative validity of a semi-quantitative FFQ created for use in Tanzania by comparing it with two 24 h diet recalls.

DESIGN

We measured relative validity of the FFQ with deattenuated energy-adjusted rank correlations for nutrients, deattenuated rank correlations for food groups, and performed a cross-classification analysis of energy-adjusted nutrient quartiles using percentage of agreement and Bland-Altman analysis.

SETTING

Interviews were conducted in 2014 in participants' homes in Ukonga, Dar es Salaam, Tanzania.

SUBJECTS

We surveyed 317 adults aged 40 years or older from the general public.

RESULTS

Deattenuated energy-adjusted rank correlation coefficients of nutrients ranged from -0·03 for riboflavin to 0·41 for percentage of energy from carbohydrates, with a median correlation of 0·21. Coefficients for food groups ranged from 0·00 for root vegetables to 0·51 for alcohol, with a median of 0·35. Relative to the average of the two 24 h diet recalls, the FFQ overestimated energy intake and intakes of all nutrients and food groups, other than tea, with ratios among nutrients ranging from 1·34 for SFA to 7·08 for vitamin A; and among food groups from 0·92 for tea to 9·00 for fruit. The percentage of participants classified into the same nutrient intake quartile ranged from 23 % for SFA to 32 % for both niacin and pantothenic acid, with a median of 28 %.

CONCLUSIONS

The FFQ performed moderately well in urban Tanzanian adults.

Assessment of Validity and Reproducibility of the Zinc-Specific Dietary Intake Questionnaire Conducted for Young Polish Female Respondents

One of the brief methods enabling the assessment of the zinc intake and identification of individuals characterized by insufficient zinc intake, is zinc-specific food frequency questionnaire. The aim of the study was to assess the validity and reproducibility of the elaborated zinc-specific food frequency questionnaire ZINC-FFQ (Zinc INtake Calculation—Food Frequency Questionnaire) in a group of young Polish female respondents. The validity was assessed in comparison with 3-day dietary records, while reproducibility was assessed for the ZINC-FFQ filled in twice (FFQ1 and FFQ2—six weeks apart). Bland–Altman indexes in the assessment of validity were 5.5% (FFQ1) and 6.7% (FFQ2), while in assessment of reproducibility it was 3.3%. In the assessment of reproducibility, 83% of respondents were classified into the same category of zinc intake adequacy and 72% of respondents were classified into the same tertile, that contributed to weighted κ statistic of 0.65 (substantial agreement). It may be concluded, that ZINC-FFQ is characterized by a validity on a satisfactory and reproducibility on a very good level, in a group of young Polish female respondents, and may be applied to indicate individuals characterized by the risk of insufficient intake.

Insufficient intake of alpha-linolenic fatty acid (18:3n-3) during pregnancy and associated factors

ABSTRACT Objective: To analyze alpha-linolenic fatty acid intake in two cohorts of pregnant women, and to identify factors associated with alpha-linolenic acid intake. Methods: This is a cohort study involving pregnant women with low obstetric risk (N=353) in public health system from a municipality of São Paulo state, Brazil. In each trimester, two 24-hour food recalls were collected. Descriptive analyses of dietary lipid profiles were performed, followed by a multiple comparison test. According to the trimester of pregnancy, differences were assessed using the mean difference test. To evaluate the adequacy of linoleic fatty acid and alpha-linolenic acid intake, the adequate intake test was used. The association between alpha-linolenic acid intake adequacy and maternal characteristics was investigated using a binary logistic regression model. Results: Total lipids intake and the percentage contribution to dietary energy met recommended levels. One-third of the diets demonstrated a lower than daily recommended intake of alpha-linolenic acid. Overweight pregnant women were twice as likely to have inadequate alpha-linolenic acid intake. Pregnant women from a more disadvantaged socioeconomic situation had greater risks of inadequate intake. Conclusion: Over-intake of lipids is not problematic, but quality is an issue, with one third of the pregnant women and their fetuses exposed to adverse effects due to low intake of omega-3 fatty acids, indicating important nutritional vulnerability in this population.

Relative validation of a short questionnaire to assess the dietary habits of pregnant American Indian women

The objective of this study was to compare a short dietary screener developed to assess diet quality with interviewer‐administered telephone 24‐hour dietary recalls in a population of pregnant Northern Plains (NP) American Indian women. Participants were recruited from NP clinical sites of the Prenatal Alcohol and SIDS and Stillbirth (PASS) Network, as part of a large, prospective, multidisciplinary study. Prenatal PASS participants who enrolled prior to 24 weeks gestation were eligible to participate. Repeated 24‐hour dietary recalls were collected using the Nutrition Data System for Research (NDSR) software and a short dietary screener was administered intended to capture usual dietary intake during pregnancy. The available recalls were averaged across days for analysis. Items were grouped from the recalls to match the food group data estimates for the screener (e.g., total vegetables, total fruit, total dairy, total and whole grains). Deattenuated Pearson correlation coefficients were calculated between the two data sources after correcting for the within‐person variation in the 24‐hour recall data. A total of 164 eligible women completed the screener and at least two 24‐hour dietary recalls and were included in the analyses. Pearson deattenuated correlation coefficients between the diet screener and the dietary recalls for the majority of food groups were 0.40 or higher. This short diet screener to assess usual diet appears to be a valid instrument for use in evaluating diet quality among pregnant American Indian women.

Validation of a food frequency questionnaire for Japanese pregnant women with and without nausea and vomiting in early pregnancy

BACKGROUND

No previous study has shown the validity of a food frequency questionnaire (FFQ) in early pregnancy with consideration of nausea and vomiting during pregnancy (NVP). The aim of this study was to evaluate the validity of a FFQ in early pregnancy for Japanese pregnant women.

METHOD

We included 188 women before 15 weeks of gestation and compared estimated nutrient intake and food group intake based on a modified FFQ with that based on 3-day dietary records (DRs). Spearman's rank correlation coefficients, adjusting energy intake and attenuating within-person error, were calculated. Subgroup analysis for those with and without NVP was conducted. We also examined the degree of appropriate classification across categories between FFQ and DRs through division of consumption of nutrients and food groups into quintiles.

RESULTS

Crude Spearman's correlation coefficients of nutrients ranged from 0.098 (sodium) to 0.401 (vitamin C), and all of the 36 nutrients were statistically significant. In 27 food groups, correlation coefficients ranged from -0.015 (alcohol) to 0.572 (yogurt), and 81% were statistically significant. In subgroup analysis, correlation coefficients in 89% of nutrients and 70% of food groups in women with NVP and 97% of nutrients and 74% of food groups in women without NVP were statistically significant. On average, 63.7% of nutrients and 60.4% of food groups were classified into same or adjacent quintiles according to the FFQ and DRs.

CONCLUSIONS

The FFQ is a useful instrument, regardless of NVP, for assessing the diet of women in early pregnancy in Japan.

Adherence to a lifestyle programme in overweight/obese pregnant women and effect on gestational diabetes mellitus: a randomized controlled trial

This study aims to determine whether the prescription of a detailed lifestyle programme in overweight/obese pregnant women influences the occurrence of gestational diabetes (GDM), and if this kind of prescription increases the adherence to a healthier lifestyle in comparison to standard care. The study was designed as a randomized controlled trial, with open allocation, enrolling women at 9-12 weeks of pregnancy with a BMI ≥ 25 kg/m² . The women assigned to the Intervention group (I = 96) received a hypocaloric, low-glycaemic, low-saturated fat diet and physical activity recommendations. Those assigned to the Standard Care group (SC = 95) received lifestyle advices regarding healthy nutrition and exercise. Follow-up was planned at the 16^th , 20^th , 28^th and 36^th weeks. A total of 131 women completed the study (I = 69, SC = 62). The diet adherence was higher in the I (57.9%) than in the SC (38.7%) group. GDM occurred less frequently in the I (18.8%) than in the SC (37.1%, P = 0.019) group. The adherent women from either groups showed a lower GDM rate (12.5% vs. 41.8%, P < 0.001). After correcting for confounders, the GDM rate was explained by allocation into the I group (P = 0.034) and a lower BMI category (P = 0.039). The rates of hypertension, preterm birth, induction of labour, large for gestational age babies and birthweight > 4000 g were significantly lower in I group. The incidence of small for gestational age babies was not different. These findings demonstrate that the adherence to a personalized, hypocaloric, low-glycaemic, low-saturated fat diet started early in pregnancy prevents GDM occurrence, in women with BMI ≥ 25 kg/m² .

Misreport of energy intake assessed with food records and 24-h recalls compared with total energy expenditure estimated with DLW

BACKGROUND/OBJECTIVES

The accuracy of dietary assessment methods has rarely been validated using precise techniques. The objective of this work was to evaluate the validity of energy intake (EI) estimated with food records (FRs) and 24-h recalls (24hRs) against total energy expenditure (EE) estimated by the doubly labeled water (DLW) method. In addition, the magnitude of EI under-reporting was assessed along with its associated characteristics.

SUBJECTS/METHODS

The studied group included 83 adults between 20 and 60 years of age who were recruited from a population-based sample. Within-person variation-adjusted means of EI estimated from two FRs and three 24hRs were compared with EE estimated using the DLW method multiple-point protocol. The Wilcoxon signed-rank test was used to assess the differences between EI and EE, whereas Bland-Altman and survival-agreement plots assessed the agreement between the estimates.

RESULTS

The mean EE (2540 kcal) was greater than the mean reported EI for both dietary assessment methods (FR: 1774 kcal; 24hR: 1658 kcal, P<0.01). The frequency of under-reporting was lower (20%) for EI estimated with the 24hR than that estimated with the FR (32%). Men presented lower magnitude of under-reported EI than women did. For women, differences between EI and EE were lower with FR than with 24hR. Overall, FR and 24hR showed similar performance. The mean under-reported EI was ~30% for both methods.

CONCLUSIONS

Irregular meal habits, smoking and low education were associated with the under-report of EI. Both FR and 24hR are subjected to bias suggesting the need of refining the procedures applied in dietary assessment methods.

Transgenerational effects of maternal diet on metabolic and reproductive ageing

The early-life environment, in particular maternal diet during pregnancy, influences a wide range of organs and systems in adult offspring. Mounting evidence suggests that developmental programming can also influence health and disease in grand-offspring. Transgenerational effects can be defined as those persisting into an F2 generation, where the F0 mother experiences suboptimal diet during her pregnancy. In this review, we critically examine evidence for transgenerational developmental programming effects in human populations, focusing on metabolic and reproductive outcomes. We discuss evidence from historical cohorts suggesting that grandchildren of women exposed to famine and other dietary alterations during pregnancy may experience increased rates of later health complications than their control counterparts. The methodological difficulties with transgenerational studies in human cohorts are explored. In particular, the problems with assessing reproductive outcomes in human populations are discussed. In light of the relative paucity of evidence available from human cohorts, we consider key insights from transgenerational experimental animal models of developmental programming by maternal diet; data are drawn from a range of rodent models, as well as the guinea-pig and the sheep. The evidence for different potential mechanisms of transgenerational inheritance or re-propagation of developmental programming effects is evaluated. Transgenerational effects could be transmitted through methylation of the gametes via the paternal and maternal lineage, as well as other possible mechanisms via the maternal lineage. Finally, future directions for exploring these underlying mechanisms further are proposed, including utilizing large, well-characterized, prospective pregnancy cohorts that include biobanks, which have been established in various populations during the last few decades.

Validation of a Food Frequency Questionnaire for Estimating Micronutrient Intakes in an Urban US Sample of Multi-Ethnic Pregnant Women

OBJECTIVE(S)

To validate the Block98 food frequency questionnaire (FFQ) for estimating antioxidant, methyl-nutrient and polyunsaturated fatty acids (PUFA) intakes in a pregnant sample of ethnic/racial minority women in the United States (US).

METHODS

Participants (n = 42) were from the Programming of Intergenerational Stress Mechanisms study. Total micronutrient intakes from food and supplements was ascertained using the modified Block98 FFQ and two 24-h dietary recalls collected at random on nonconsecutive days subsequent to completion of the FFQ in mid-pregnancy. Correlation coefficients (r) corrected for attenuation from within-person variation in the recalls were calculated for antioxidants (n = 7), methyl-nutrients (n = 8), and PUFAs (n = 2).

RESULT(S)

The sample was largely ethnic minorities (38 % Black, 33 % Hispanic) with 21 % being foreign born and 41 % having less than or equal to a high school degree. Significant and adequate deattenuated correlations (r ≥ 0.40) for total dietary intakes of antioxidants were observed for vitamin C, vitamin E, magnesium, and zinc. Reasonable deattenuated correlations were also observed for methyl-nutrient intakes of vitamin B6, betaine, iron, and n:6 PUFAs; however, they did not reach significance. Most women were classified into the same or adjacent quartiles (≥70 %) for total (dietary + supplements) estimates of antioxidants (5 out of 7) and methyl-nutrients (4 out of 5).

CONCLUSIONS

The Block98 FFQ is an appropriate dietary method for evaluating antioxidants in pregnant ethnic/minorities in the US; it may be less efficient in measuring methyl-nutrient and PUFA intakes.

Reproducibility and relative validity of a semi-quantitative food frequency questionnaire for Chinese pregnant women

BACKGROUND

Food frequency questionnaire (FFQ) is a reliable tool to estimate dietary intake in large nutritional epidemiological studies, but there is lack of a current and validated FFQ for use in urban Chinese pregnant women. This study aimed to evaluate the reproducibility and validity of a semi-quantitative FFQ designed to estimate dietary intake among urban pregnant women in a cohort study conducted in central China.

METHODS

In the reproducibility study, a sample of 123 healthy pregnant women completed the first FFQ at 12-13 weeks gestation and the second FFQ 3-4 weeks later. To validate the FFQ, the pregnant women completed three 24-h recalls (24HRs) between the intervals of two FFQs.

RESULTS

The intraclass correlation coefficients of two administrations of FFQ for foods ranged from 0.23 (nuts) to 0.49 (fruits) and for nutrients from 0.24 (iodine) to 0.58 (selenium) and coefficients were all statistically significant. The unadjusted Pearson correlation coefficients between two methods ranged from 0.28 (beans) to 0.53 (fruits) for foods and from 0.15 (iodine) to 0.59 (protein) for nutrients. Energy-adjusted and de-attenuated correlation coefficients for foods ranged from 0.35 (beans) to 0.56 (fruits) and for nutrients from 0.11 (iodine) to 0.63 (protein), and all correlations being statistically significant except for iodine, sodium and riboflavin. On average, 67.0% (51.2%-80.5%) of women were classified by both methods into the same or adjacent quintiles based on their food intakes, while 68.5% (56.1%-77.2%) of women were classified as such based on nutrient intakes. Extreme misclassifications were very low for both foods (average of 2.0%) and nutrients (average of 2.2%). Bland-Altman Plots also showed reasonably acceptable agreement between two methods.

CONCLUSION

This FFQ is a reasonably reliable and valid tool for assessing most food and nutrient intakes of urban pregnant women in central China.

Application and interpretation of multiple statistical tests to evaluate validity of dietary intake assessment methods

BACKGROUND

Several statistical tests are currently applied to evaluate validity of dietary intake assessment methods. However, they provide information on different facets of validity. There is also no consensus on types and combinations of tests that should be applied to reflect acceptable validity for intakes. We aimed to 1) conduct a review to identify the tests and interpretation criteria used where dietary assessment methods was validated against a reference method and 2) illustrate the value of and challenges that arise in interpretation of outcomes of multiple statistical tests in assessment of validity using a test data set.

METHODS

An in-depth literature review was undertaken to identify the range of statistical tests used in the validation of quantitative food frequency questionnaires (QFFQs). Four databases were accessed to search for statistical methods and interpretation criteria used in papers focusing on relative validity. The identified tests and interpretation criteria were applied to a data set obtained using a QFFQ and four repeated 24-hour recalls from 47 adults (18-65 years) residing in rural Eastern Cape, South Africa.

RESULTS

102 studies were screened and 60 were included. Six statistical tests were identified; five with one set of interpretation criteria and one with two sets of criteria, resulting in seven possible validity interpretation outcomes. Twenty-one different combinations of these tests were identified, with the majority including three or less tests. Coefficient of correlation was the most commonly used (as a single test or in combination with one or more tests). Results of our application and interpretation of multiple statistical tests to assess validity of energy, macronutrients and selected micronutrients estimates illustrate that for most of the nutrients considered, some outcomes support validity, while others do not.

CONCLUSIONS

One to three statistical tests may not be sufficient to provide comprehensive insights into various facets of validity. Results of our application and interpretation of multiple statistical tests support the value of such an approach in gaining comprehensive insights in different facets of validity. These insights should be considered in the formulation of conclusions regarding validity to answer a particular dietary intake related research question.