Using the method of triads in the validation of a food frequency questionnaire to assess the consumption of fatty acids in adults.

BACKGROUND: It is of great value to develop valid instruments to estimate food consumption; for this purpose, the triads method has been applied in validation studies of dietary intake to evaluate the correlation between three measurements [food frequency questionnaire (FFQ), reference method and biomarker]. The main aim of the present study was to validate a FFQ for Brazilian adults by means of the method of triads by estimating the ingestion of total fatty acids based on the level of saturation. METHODS: The present study enrolled 152 Brazilian adults of both sexes, who were residents in the city of Viçosa, Brazil. The ingestion of total saturated, monounsaturated, polyunsaturated, trans, linoleic and linolenic fatty acids was assessed by means of a FFQ, two food records, and biomarkers, which were detected by gas chromatography. The validation coefficients were calculated using the method of triads and concordance was determined by Kappa statistics. RESULTS: The FFQ was considered an adequate dietary method, because, based on the validation coefficients, it estimates the intake of total fat (0.84), as well as linolenic (0.90) and linoleic acids (0.31). A high concordance rate was confirmed for all nutrients assessed by the FFQ and food records. Regarding the biomarkers, linolenic acid and linoleic acid presented greater concordance. CONCLUSIONS: According to the validation coefficients, the FFQ precisely estimated total fat, linolenic acid and linoleic acid contents.

An overview of folate status in a population-based study from São Paulo, Brazil and the potential impact of 10 years of national folic acid fortification policy.

BACKGROUND/OBJECTIVES: Food fortification is an important strategy in public health policy for controlling micronutrient malnutrition and a major contributing factor in the eradication of micronutrients' deficiencies. Approximately 50 countries worldwide have adopted food fortification with folic acid (FA). FA fortification of wheat and maize flours has been mandatory in Brazil since 2004. To assess the effect of 10 years of FA food fortification policy on folate status of residents of São Palo, Brazil using a population-based survey. SUBJECTS/METHODS: Data were from 750 individuals aged ⩾12 years who participated in a cross-sectional population-based survey in São Paulo city, Brazil. Fasting blood samples were collected, and folate was assayed by affinity-high performance liquid chromatografy method with electrochemical detection. The participants provided information about food intake based on two 24 h dietary recall. RESULTS: Only 1.76% of population had folate deficiency (<6.8 nmol/l). The mean folate concentration was 29.5 (95% confidence interval: 27.3-31.7) nmol/l for all sex-age groups. The mean folate intake for the population was 375.8 (s.e.m.=6.4) µg/day of dietary folate equivalents (DFEs). When comparing folate intake in DFE from food folate and FA from fortified foods, FA contributed 50% or more of the DFE in almost all sex-age groups. The major contributors of folate intake are processed foods made from wheat flour fortified with FA, especially among subjects younger than 20 years old. CONCLUSIONS: The deficiency of folate is very low, and food fortification contributed to folate intake and had a notable influence on rankings of food contributors of folate.

Agreement between Dietary Intake of Older Adults and Proxy Respondents Assessed by a Food Frequency Questionnaire.

OBJECTIVE: To evaluate the degree of agreement of dietary intake reported by the patient subject with the dietary intake reported by a respondent (a next-of-kin or a caregiver), collected by a validated Food Frequency Questionnaire (FFQ). METHODOLOGY: 126 adults, both sexes, the average age was 65.9 years for patients and 54.4 years for respondents. They were recruited from the General Practice Clinic at the Clinical Hospital of São Paulo (AGD-FMUSP). The agreement between the responses given by patients and respondents was assessed using Spearman, weighted Kappa and Bland Altman tests. RESULTS: The analysis for accuracy between responses (Spearman test) showed a moderate degree of agreement (0.31-0.39) for Energy, Total fat, Total Saturated Fatty Acids (SFA), Total Monounsaturated Fatty Acids (MUFA). Regarding food groups a moderate agreement was found for the majority of the foods (fruits (0.30), dairy products (0.50), natural juices (0.45), beans (0.48), butter/margarine (0.55), coffee (0.41) and soda (0.45), with the exception of vegetables (0.12) and rice (0.63). The ingestion differences did not exceeded the limit of the two standard deviations for the majority of the pairs (Bland Altman). A respondent subsample composed only of husband/wives (N = 36) revealed a moderate agreement concordance for most macronutrients studied (0.30 - 0.58), except polyunsaturated fats (0.25). CONCLUSION: The results of this study show that, the FFQ may be used in cases where is impossible to get the answers directly from the patients.

Evaluation of the psychometric properties of the main meal quality index when applied in the UK population.

BACKGROUND/OBJECTIVES: The aim of this study was to evaluate the validity and reliability of the Main Meal Quality Index when applied on the UK population. SUBJECTS/METHODS: The indicator was developed to assess meal quality in different populations, and is composed of 10 components: fruit, vegetables (excluding potatoes), ratio of animal protein to total protein, fiber, carbohydrate, total fat, saturated fat, processed meat, sugary beverages and desserts, and energy density, resulting in a score range of 0-100 points. The performance of the indicator was measured using strategies for assessing content validity, construct validity, discriminant validity and reliability, including principal component analysis, linear regression models and Cronbach's alpha. RESULTS: The indicator presented good reliability. CONCLUSIONS: The Main Meal Quality Index has been shown to be valid for use as an instrument to evaluate, monitor and compare the quality of meals consumed by adults in the United Kingdom.

Comparisons of physical activity, adipokines, vitamin D status and dietary vitamin D intake among adolescents.

BACKGROUND: Considering that lifestyle and diet are key factors responsible for the increases in adiposity in youth, it is important to understand how vitamin D, adipokines and markers of glucose metabolism are related to physical activity level (PAL) during growth. The present study aimed to investigate associations between physical activity level, adiponectin/leptin ratio, vitamin D status and dietary vitamin D intake among adolescents. METHODS: A cross-sectional study was conducted with adolescents aged 14-18 years old who were living in São Paulo, Brazil. Serum 25 hydroxyvitamin D [25(OH)D], adiponectin (A), leptin (L), glucose and insulin were obtained after 12 h of fasting. Dietary calcium and vitamin D intake were measured by 24-h food record, as repeated in 62.6% of the sample. PAL was measured by the International Physical Activity Questionnaire (IPAQ). Pearson's chi-square test, Pearson correlation and linear regression analysis were performed. RESULTS: A total of 198 subjects, mean (SD) age 16.3 (1.4) years, 51% male, were enrolled in the study. Some 9% of participants were sedentary, 22% were insufficiently active (IA), 51% were active and 18% were very active (VA). The A/L ratio was lower among sedentary/IA subjects [2.2 (4.0) versus 5.6 (12.3); P = 0.01] compared to active/VA subjects. PAL was not associated with vitamin D status or markers of glucose metabolism. Serum 25(OH)D positively associated with vitamin D intake, after adjusting for sex, sun exposure and season of the year in regression analysis (partial r2 =0.026, P = 0.02). CONCLUSIONS: Low PAL was associated with a lower A/L ratio. Vitamin D status was not associated with sun exposure habits, although it was positively correlated with vitamin D intake.

Indices for the assessment of nutritional quality of meals: a systematic review.

This systematic review aimed to synthesise information on indices developed to evaluate nutritional quality of meals. A strategy for systematic search of the literature was developed using keywords related to assessment of meal quality. Databases searched included ScienceDirect, PubMed, Lilacs, SciELO, Scopus, Cochrane, Embase and Google Scholar. The literature search resulted in seven different meal quality indices. Each article was analysed in order to identify the following items: authors, country, year, study design, population characteristics, type of meal evaluated, dietary assessment method, characteristics evaluated (nutrients or food items), score range, index components, nutritional references, correlations performed, validation and relationship with an outcome (if existing). Two studies developed instruments to assess the quality of breakfast, three analysed lunch, one evaluated dinner and one was applied to all types of meals and snacks. All meal quality indices reviewed were based on the evaluation of presence or absence of food groups and relative contributions of nutrients, according to food-based guidelines or nutrient references, adapting the daily dietary recommendations to one specific meal. Most of the indices included three items as components for meal quality assessment: (I) total fat or some specific type of fat, (II) fruits and vegetables and (III) cereals or whole grains. This systematic review indicates aspects that need further research, particularly the numerous approaches to assessing meals considering different foods and nutrients, and the need for validation studies of meal indices.

Dietary intake and food contributors of polyphenols in adults and elderly adults of Sao Paulo: a population-based study.

A comprehensive estimation of polyphenol intake is needed to gain a better understanding of the association between polyphenol-rich food intake and the potential effects of this intake on chronic diseases. The aim of this study was to estimate the intake of polyphenols and the major dietary contributors in the population of Sao Paulo. Data were obtained from the Health Survey-São Paulo (ISA-Capital 2008) and were reported for 1103 adults and elderly adults. Food intake was estimated by one 24-h dietary recall (24HR). Polyphenol intake was calculated by matching food consumption data from the 24HR with the polyphenol content in foods listed in the Phenol-Explorer database. The mean total intake of polyphenols was 377·5 (se 15·3) mg/d. The main polyphenol classes were phenolic acids (284·8 (se 15·9) mg/d) and flavonoids (54·6 (se 3·5) mg/d). Intakes were higher in the elderly adults than in other adults (P<0·001) and higher in individuals with lower educational level (P=0·01) and current smokers (P=0·02). The main dietary contributors for total polyphenols were coffee (70·5 %), citrus fruits (4·6 %) and tropical fruits (3·4 %). Coffee was the major source of polyphenols, providing 266·2 (se 16·5) mg/d, and contributed 92·3 % of the phenolic acids and 93·1 % of the alkylmethoxyphenols. These findings will be useful for assessing the potential role on health of polyphenols and specific polyphenol-rich foods, such as coffee, and enable a comparison with people from other countries.

High intake of heterocyclic amines from meat is associated with oxidative stress.

High meat intake has been related to chronic diseases such as cancer and CVD. One hypothesis is that heterocyclic amines (HCA), which are formed during the cooking process of meat, can generate reactive species. These compounds can cause oxidation of lipids, proteins and DNA, resulting in oxidative stress, cell damage and loss of biological function. This association has been seen in vitro; however, it remains unclear in vivo. The aim of the present study was to investigate the association between oxidative stress and HCA intake, and oxidative stress and meat intake. Data were from the Health Survey for Sao Paulo--ISA-Capital (561 adult and elderly). Food intake was estimated by one 24-h dietary recall (24HR) complemented by a detailed FFQ with preferences of cooking methods and level of doneness for meat. HCA intake was estimated linking the meat from the 24HR to a database of HCA. Oxidative stress was estimated by malondialdehyde (MDA) concentration in the plasma, after derivatisation with thiobarbituric acid and quantification by HPLC/diode array. Analyses were performed using multivariate logistic regressions adjusted for smoking, sex, age, BMI, skin colour, energy intake, fruit and vegetable intake, and physical activity. A positive association between HCA intake and MDA concentration (OR 1·17; 95% CI 1·01, 1·38) was observed, showing that HCA from meat may contribute to increase oxidative stress, and may consequently increase the risk of chronic diseases.

Is the food frequency consumption essential as covariate to estimate usual intake of episodically consumed foods?

UNLABELLED: BACKGROUNDS/OBJECTIVES: The aim of this paper is to verify the performance of the frequency of consumption as variable for prediction of the usual intakes of foods. SUBJECTS/METHODS: In total, 725 individuals who answered two nonconsecutive 24-h recall and one food frequency questionnaire (FFQ) in the 'Healthy Survey-Sao Paulo-Brazil'. An additional indicator variable indicating if one is usual consumer was created before analyzing. The Multiple Source Method and National Cancer Institute method were used to estimate usual intake of selected food considering different models of prediction: with no covariates; with FFQ; with FFQ plus indicator variable; and with only indicator variable. RESULTS: For foods that are consumed every day or almost every day, the inclusion of the FFQ and/or the indicator variable as covariates resulted in similar percentiles of consumption when compared with the model with no covariates. For episodically consumed foods, the models with FFQ plus indicator variable and with only indicator variable estimated similar percentiles of intake. CONCLUSIONS: The use of the indicator variable instead the FFQ appears as a good alternative to estimate usual intake of episodically consumed foods.

The influence of breakfast and dairy products on dietary calcium and vitamin D intake in postpubertal adolescents and young adults.

BACKGROUND: Given the importance of both calcium and vitamin D for bone health and the high prevalence of vitamin D from around the world, the present study aimed to evaluate calcium and vitamin D intake in a group of healthy Brazilian adolescents and young adults and to examine the influence of breakfast and dairy products in the total intake of these nutrients. METHODS: One hundred and sixty adolescents and young adults, aged 16-20 years old, from a public school, participated in the present study. Three-day dietary records were used to assess calcium and vitamin D intakes. Serum 25(OH)D levels were measured using a radioimmunoassay kit. The results were expressed as the mean (SD). RESULTS: Only 3.8% of the subjects met the daily adequate intake recommendation for calcium, and none for vitamin D [682.2 (132.2)mg day(-1) and 124.0 (28.0)IU day(-1) , respectively]. 25(OH)D serum levels were insufficient in 51.5% and deficient in 9.7% of the individuals [72.5 (22.3) nmol L(-1) ]. There was a significant positive correlation between dairy product intake with both calcium and vitamin D (r=0.597 and r =0.561, respectively; P=0.000). Adolescents who ate breakfast had a significant higher mean calcium, vitamin D and dairy product intake than adolescents who did not report this meal. CONCLUSIONS: The majority of adolescents and young adults did not consume recommended intakes of calcium and vitamin D and also presented 25(OH)D insufficiency. The results indicate that a regular breakfast and the consumption of dairy products represent important strategies in improving calcium and vitamin D intake in the diet.

Complementary feeding: study on prevalence of food intake in two health centers of São Paulo city.

The infant feeding practices in the first year of life are of fundamental importance for their growth and development. This study was carried out aiming at checking on the prevalence of food intake by the infants during their first year of life. One-hundred-and-seventy-five children aged up to one year, attended to in two Health Centers of São Paulo city, Brazil, participated in this study. Their feeding practices, obtained through the status quo approach, were analyzed through multiple logistic regression models, using curves of prevalence for complementary food consumption. Fruit was the first solid food to be part of the infant diet, followed by vegetables, cereal, meat and/or eggs and, beans. Animal-protein-containing source foods (meat and eggs) entered the diet much later, being consumed by practically all children only at the end of their first year of life. The early introduction of complementary foods into the infant diet was made evident. The introduction of solid foods to complement breastfeeding is started with low-calorie density foods, in disagreement with the recommendations for Brazilian children. Results of this paper disclose a need for having programmatic actions in health education being carried out, in special those regarding exclusive breastfeeding promotion and orientation on the adequate introduction of complementary feeding.