Data on the prevalence of birth defects and neural tube defects (NTD) in Latin America are limited. The present review summarizes NTD prevalence and time trends in Latin American countries and compares pre- and post-fortification periods to assess the impact of folic acid fortification in these countries.

We carried out a literature review of studies and institutional reports published between 1990 and 2010 that contained information on NTD prevalence in Latin America.

NTD prevalence in Latin American countries varied from 0·2 to 9·6 per 1000 live births and was influenced by methods of ascertainment. Time trends from Bogota, Costa Rica, Dominican Republic, Guatemala City, Mexico and Puerto Rico showed average annual declines of 2·5 % to 21·8 %. Pre- and post-fortification comparisons were available for Argentina, Brazil, Chile, Costa Rica, Puerto Rico and Mexico. The aggregate percentage decline in NTD prevalence ranged from 33 % to 59 %.

The present publication is the first to review data on time trends and the impact of folic acid fortification on NTD prevalence in Latin America. Reported NTD prevalence varied markedly by geographic region and in some areas of Latin America was among the lowest in the world, while in other areas it was among the highest. For countries with available information, time trends showed significant declines in NTD prevalence and these declines were greater in countries where folic acid fortification of staples reached the majority of the population at risk, such as Chile and Costa Rica.

To compare the dietary intakes of Dutch nutrition and dietetics students with the Dutch RDA and the Dutch National Food Consumption Survey (DNFCS), and to assess whether dietary intake changes during education.

Cross-sectional and longitudinal research (2004–2010).

Data collection by 7 d dietary record and questionnaire.

Dutch nutrition and dietetics students.

Three hundred and fifty-two first-year and 216 fourth-year students were included. One hundred and thirty-three students in three cohorts were assessed twice. Of first-year students, >80 % met the RDA for all macronutrients. Of these students only 37 % met the RDA for fibre and in 43 % intake of saturated fat was too high. Fourth-year students more often met the RDA for fruits (55 %) and vegetables (74 %) compared with first-year students (32 % and 40 %, respectively). Intake of fruits and vegetables of both first- and fourth-year students was much higher than that of DNFCS participants (where 2 % and 7 %, respectively, met the corresponding RDA). Only <25 % of fourth-year students met the RDA for Fe, Se and vitamin D. In the cohorts, dietary intake for all macronutrients stabilised from the first to the fourth year (>80 %). Intakes of dietary fibre, Ca, Mg, Se, riboflavin, niacin, fruits, vegetables and fish improved significantly during education.

Dietary intake of nutrition and dietetics students is much better than that of DNFCS participants and improved during education. However, there is still a gap between actual dietary intake and the RDA, especially for Fe, Se and vitamin D.

To validate a brief FFQ developed for capturing short-term antioxidant intake in a sample of US college students.

A seventy-four-item antioxidant FFQ was developed based on major antioxidant sources in the American diet. The FFQ was validated against 30 d food records (FR) and plasma antioxidant concentrations. The reliability of the FFQ was evaluated by two FFQ administered at a 1-month interval.

University of Connecticut, CT, USA.

Sixty healthy college students.

Estimates of dietary antioxidants from the FFQ were moderately to highly correlated with those estimated from the 30 d FR (r = 0·29–0·80; P < 0·05) except for γ-tocopherol and β-cryptoxanthin. Total antioxidant capacity from diet only or from diet and supplements estimated by the 30 d FR and FFQ were highly correlated (r = 0·67 and 0·71, respectively; P < 0·0001). The FFQ categorized 91 % of participants into the same or adjacent tertiles of antioxidant intake as the 30 d FR. Most dietary carotenoids estimated from the FFQ were correlated with plasma levels (P < 0·05). Correlation coefficients for test–retest reliability ranged from 0·39 to 0·86. More than 94 % of the participants were classified in the same or adjacent tertiles between the two administrations of the FFQ.

The brief FFQ demonstrated reasonable validity for capturing a comprehensive antioxidant intake profile. This FFQ is applicable in epidemiological or clinical studies to capture short-term antioxidant intake or to simply document the variations of antioxidant intake in intervention trials. Cross-validation studies are warranted in other target populations.

To assess the association between the consumption of sugar-sweetened carbonated beverages (SSCB) and obesity in children and adolescents from Navarra (Spain).

We used a matched case–control study design. The exposure, SSCB consumption (1 serving: 200 ml), was measured with a previously validated FFQ. Anthropometrical measures were taken using standardized protocols. The outcome, obesity, was defined as BMI above the age- and sex-specific 97th percentile according to the Spanish reference charts. In the analysis we used conditional logistic regression. Potential confounders were controlled using a multivariable model.

Subjects were recruited in the paediatric departments of the Universidad de Navarra Clinic and the Navarra Hospital Complex, and in three primary health centres of Navarra. Controls were recruited when attending for a routine medical examination or vaccination.

One hundred and seventy-four obese children and 174 individually sex- and age-matched controls, 52·87 % boys, with a mean age of 11·6 years. Exclusion criteria were dietary interventions, exposure to hormone treatment, development of secondary obesity due to endocrinopathy and serious intercurrent illness.

Independently of other factors, high consumption of SSCB (>4 servings/week) was significantly associated with obesity (OR = 3·46; 95 % CI 1·24, 9·62; P = 0·01). Besides, each additional daily serving of SSCB was associated with a 69 % relative increase in the risk of obesity (OR = 1·69; 95 % CI 1·04, 2·73; P = 0·03).

We found a strong and significant association between SSCB consumption and obesity risk. Our results suggest a monotonic dose–response linear shape for this association in children and adolescents (P for trend = 0·02).

In 2011, the US Institute of Medicine updated the definition of vitamin D inadequacy to serum 25-hydroxyvitamin D (25(OH)D) concentration of 30–<50 nmol/l and of deficiency to serum 25(OH)D < 30 nmol/l. We describe the prevalence of these conditions according to these definitions, seasonal variation in 25(OH)D and predictors of serum 25(OH)D concentrations among working, white women.

Participants recorded lifestyle factors and dietary intake and provided fasting blood samples for measurement of serum 25(OH)D in both summer and winter. Predictors of serum 25(OH)D variation were analysed using linear regression and generalized linear mixed models.

Kingston General Hospital in Kingston, Ontario, Canada, from April 2008 to July 2009.

Female premenopausal nurses (n 83) working full-time rotating shifts.

Deficient or inadequate vitamin D status was observed in 9 % of participants following summer/autumn and in 13 % following winter/spring. Predictors of serum 25(OH)D concentration were vitamin D supplement use, tanning bed use and season. Tanning bed use increased serum 25(OH)D by 23·24 nmol/l (95 % CI 8·78, 37·69 nmol/l, P = 0·002) on average.

According to the 2011 Institute of Medicine bone health guidelines, over 10 % of nurses had deficient or inadequate vitamin D status following winter. Higher serum concentrations were associated with use of tanning beds and vitamin D supplements. As health promotion campaigns and legal restrictions are successful in reducing tanning bed use among women, our data suggest that increased prevalence of vitamin D inadequacy and deficiency may be a consequence, and that low vitamin D status will need to be countered with supplementation.

As part of a larger evaluation of school nutrition programmes (SNP), the present study examined programme coordinators’ perceptions of strengths, weaknesses, opportunities and threats (SWOT) regarding their SNP and public health professionals’ support.

Qualitative interviews were conducted with twenty-two of eighty-one programme coordinators who had completed a programme evaluation survey. Interviews followed a SWOT framework to evaluate programmes and assessed coordinators’ perceptions regarding current and future partnerships with public health professionals.

The study was conducted in a large, urban region within Ontario.

The twenty-two coordinators who participated represented a cross-section of elementary, secondary, Public and Catholic schools.

SNP varied enormously in foods/services offered, how they offered them and perceived needs. Major strengths included universality, the ability to reach needy students and the provision of social opportunities. Major weaknesses included challenges in forming funding partnerships, lack of volunteers, scheduling and timing issues, and coordinator workload. Common threats to effective SNP delivery included lack of sustainable funding, complexity in tracking programme use and food distribution, unreliable help from school staff, and conflicts with school administration. Opportunities for increased public health professionals’ assistance included menu planning, nutrition education, expansion of programme food offerings, and help identifying community partners and sustainable funding.

The present research identified opportunities for improving SNP and strategies for building on strengths. Since programmes were so diverse, tailored strategies are needed. Public health professionals can play a major role through supporting menu planning, food safety training, access to healthy foods, curriculum planning and by building community partnerships.

To examine associations among diet quality and dairy group membership, membership duration and non-member status for women and school-aged children in rural Kenya.

A cross-sectional survey, using chain referral sampling, was conducted and diet quality indices and prevalence of inadequate intake (PII) were estimated using the ‘estimated average requirement’ cut-off point method from single 24 h recalls, using a Kenyan nutrient database. PII was compared among members and non-members and among membership-duration groups.

Women and children of dairy group members (n 88), across membership-duration groups (1–3, 4–6, 7–9 and 10+ years), and non-members (n 23) living among members.

Small farms in central Kenya.

Members had higher energy, percentage of energy from animal-source foods and dietary diversity. Member women and children had lower PII for respectively seven and three of eleven micronutrients. Reduced PII for milk-source micronutrients was associated with membership duration for women. Many member women (38 %) had inadequate vitamin A intake and 39 % of member children had inadequate Zn intake. Members’ PII was also high (>45 %) for Fe, Ca and vitamin B12. A higher prevalence of being overweight among member women compared with non-member women suggested nutrition transition effects of higher farm productivity.

Dairy group membership was positively associated with adequate quantity and quality of diets for women and children. Long-term membership was insufficient to address micronutrient deficiencies. Understanding and addressing barriers to better diet quality and strategies to mitigate negative nutrition transition effects are needed to optimize nutritional outcomes of dairy group membership.

To examine the prevalence of stunting and overweight in children and identify demographic, socio-economic and maternal characteristics, as well as biochemical indicators, associated with these outcomes.

A population-based, cross-sectional study was performed. Data from structured questionnaires, anthropometric measurements, and blood and stool samples were used in Poisson regression models to estimate prevalence ratios (PR) according to a hierarchical conceptual framework.

Acrelândia, western Brazilian Amazon.

Children (n 1139) aged <10 years.

Prevalence of stunting was 7·1 % (95 % CI 5·1, 9·6 %) and 3·7 % (95 % CI 2·4, 5·7 %) among children aged <5 years and ≥5 years, respectively; overweight was detected in 20·6 % (95 % CI 17·4, 24·2 %) and 9·4 % (95 % CI 7·2, 12·1 %) of children aged <5 years and ≥5 years, respectively. Among children <5 years of age, stunting was positively associated with the lowest maternal height tertile (PR = 3·09, 95 % CI 1·26, 7·63), low birth weight (PR = 2·70, 95 % CI 1·41, 5·19), diarrhoea for ≥3d (PR = 2·21, 95 % CI 1·03, 4·77) and geohelminth infections (PR = 2·53, 95 % CI 1·02, 6·13). Overweight in children <5 years of age was positively associated with caesarean delivery (PR = 1·45, 95 % CI 1·02, 2·06), birth weight ≥3500 g (PR = 1·82, 95 % CI 1·30, 2·55) and Fe deficiency (PR = 1·64, 95 % CI 1·07, 2·53). Among children aged ≥5 years, land or livestock ownership (PR = 1·85, 95 % CI 1·07, 3·22), maternal overweight (PR = 2·06, 95 % CI 1·23, 3·47), high C-reactive protein concentration (PR = 2·43, 95 % CI 1·26, 4·70), vitamin A deficiency (PR = 1·97, 95 % CI 1·13, 3·41) and high serum TAG concentration (PR = 2·16, 95 % CI 1·27, 3·68) were associated with overweight.

Overweight was more prevalent than stunting, being associated with higher household wealth, maternal overweight, caesarean delivery, high birth weight, micronutrient deficiencies and high TAG concentration. Improvements in maternal and child health care with sustainable access to healthy food are necessary to reduce short- and long-term health complications related to overweight in this population.

Iodine is an essential micronutrient needed for the production of thyroid hormones. Pregnant mothers who are deficient in iodine provide less iodine to the fetal thyroid. This results in low production of thyroid hormones by the fetal thyroid, thereby leading to compromised mental and physical development of the fetus. The current study aimed to assess the current status of iodine nutrition among pregnant mothers in Himachal Pradesh, India, a known endemic region for iodine deficiency.

Three districts, namely Kangra, Kullu and Solan, were selected.

In each district, thirty clusters (villages) were identified by utilizing the population-proportional-to-size cluster sampling methodology. In each cluster, seventeen pregnant mothers attending the antenatal clinics were included.

A total of 1711 pregnant mothers (647 from Kangra, 551 from Kullu and 513 from Solan) were studied. Clinical examination of the thyroid of each pregnant mother was conducted. Spot urine samples were collected from ten pregnant mothers in each cluster. Similarly, salt samples were collected from eleven pregnant mothers in each cluster.

Total goitre rate was 42·2 % (Kangra), 42·0 % (Kullu) and 19·9 % (Solan). The median urinary iodine concentration was 200 μg/l (Kangra), 149 μg/l (Kullu) and 130 μg/l (Solan). The percentage of pregnant mothers consuming adequately iodized salt (iodine content of 15 ppm and more) was found to be 68·3 % (Kangra), 60·3 % (Kullu) and 48·5 % (Solan).

Pregnant mothers in Kullu and Solan districts had iodine deficiency as indicated by a median urinary iodine concentration less than 150 μg/l.

Food insecurity, lack of access to food due to financial constraints, is highly associated with poor health outcomes. Households dependent on social assistance are at increased risk of experiencing food insecurity, but food insecurity has also been reported in households reporting their main source of income from employment/wages (working households). The objective of the present study was to examine the correlates of food insecurity among households reliant on employment income.

Working households reporting food insecurity were studied through analysis of the Canadian Community Health Survey, 2007–2008, employing descriptive statistics and logistic regression. Food insecurity was measured using the Household Food Security Survey Module; all provinces participated.

Canada.

Canadian households where main income was derived through labour force participation. Social assistance recipients were excluded.

For the period 2007–2008, 4 % of working households reported food insecurity. Canadian households reliant on primary earners with less education and lower incomes were significantly more likely to experience food insecurity; these differences were accentuated across some industry sectors. Residence in Quebec was protective. Working households experiencing food insecurity were more likely to include earners reporting multiples jobs and higher job stress. Visible minority workers with comparable education levels experienced higher rates of food insecurity than European-origin workers.

Reliance on employment income does not eliminate food insecurity for a significant proportion of households, and disproportionately so for households with racialized minority workers. Increases in work stress may increase the susceptibility to poor health outcomes of workers residing in households reporting food insecurity.

Data-driven approaches to dietary patterns are under-utilized; latent class analyses (LCA) are particularly rare. The present study used an LCA to identify subgroups of people with similar dietary patterns, explore changes in dietary patterns over a 10-year period and relate these dynamics to sociodemographic factors and health outcomes.

The 1998 baseline and 2008 follow-up of the Cork and Kerry Diabetes and Heart Disease Study. Diets were assessed with a standard FFQ. LCA, under the assumption of conditional independence, was used to identify mutually exclusive subgroups with different dietary patterns, based on food group consumption.

Republic of Ireland.

Men and women aged 50–69 years at baseline (n 923) and at 10-year follow-up (n 320).

Three dietary classes emerged: Western, Healthy and Low-Energy. Significant differences in demographic, lifestyle and health outcomes were associated with class membership. Between baseline and follow-up most people remained ‘stable’ in their dietary class. Most of those who changed class moved to the Healthy class. Higher education was associated with transition to a healthy diet; lower education was associated with stability in an unhealthy pattern. Transition to a healthy diet was associated with higher CVD risk factors at baseline: respondents were significantly more likely to be smokers, centrally obese and to have hypertension (non-significant).

LCA is useful for exploring dietary patterns transitions. Understanding the predictors of longitudinal stability/transitions in dietary patterns will help target public health initiatives by identifying subgroups most/least likely to change and most/least likely to sustain a change.

To describe availability and frequency of use of local snack-food outlets and determine whether reported use of these outlets was associated with dietary intakes.

Data were cross-sectional. Availability and frequency of use of three types of local snack-food outlets were reported. Daily dietary intakes were based on the average of up to four 24 h dietary recalls. Multivariable linear regression models estimated average daily intakes of energy, sugar-sweetened beverages (SSB) and snack foods/sweets associated with use of outlets.

Multi-site, observational cohort study in the USA, 2004–2006.

Girls aged 6–8 years (n 1010).

Weekly frequency of use of local snack-food outlets increased with number of available types of outlets. Girls with access to only one type of outlet reported consuming food/beverage items less frequently than girls with access to two or three types of outlets (P <0·001). Girls’ daily energy, SSB and snack foods/sweets intakes increased with greater use of outlets. Girls who reported using outlets>1 to 3 times/week consumed 0·27 (95 % CI 0·13, 0·40) servings of SSB more daily than girls who reported no use. Girls who reported using outlets>3 times/week consumed 449·61 (95 % CI 134·93, 764·29) kJ, 0·43 (95 % CI 0·29, 0·58) servings of SSB and 0·38 (95 % CI 0·12, 0·65) servings of snack foods/sweets more daily than those who reported no use.

Girls’ frequency of use of local snack-food outlets increases with the number of available types of outlets and is associated with greater daily intakes of energy and servings of SSB and snack foods/sweets.

To assess the reliability and relative validity of a diet index score derived from a Short Food Survey (SFS).

The thirty-eight-item SFS was designed to assess recent dietary intake of 4–11-year-olds to enable calculation of the Dietary Guideline Index for Children and Adolescents. Reliability was assessed based on two online administrations of the SFS, one week apart. Relative validity was assessed by comparing intakes derived from the SFS with those from the mean of three 24 h recalls. Intra-class correlations, Bland–Altman plots and estimated biases were assessed. Cohen's κ coefficients were used to determine the level of agreement between the two methods.

Adelaide, Australia.

Sixty-three parents reported on their children's intake (mean age 7·1 (sd 2·1) years).

The intra-class correlation for reliability ranged from 0·43 for dairy foods to 0·94 for beverages, and was 0·92 for total diet index score (all P < 0·01). The intra-class correlation for validity ranged from 0·04 for meat and alternatives to 0·41–0·44 for fruit, beverages and extra foods, and was 0·44 for the total diet index score. The SFS overestimated the mean diet index score by 16 %, and the bias was consistent across levels of compliance. The percentage agreement into tertiles of index scores was 84% between the administrations of the two SFS, but only 43 % when comparing the SFS with the mean of the recalls.

The SFS can provide a consistent estimate of overall compliance to dietary guidelines for children aged 4–11 years, but overestimated the total diet index score by 16 % across all levels of compliance.

To examine the effect of fast-food and full-service restaurant consumption on adults’ energy intake and dietary indicators.

Individual-level fixed-effects regression model estimation based on two different days of dietary intake data was used.

Parallel to the rising obesity epidemic in the USA, there has been a marked upward trend in total energy intake derived from food away from home.

The full sample included 12 528 respondents aged 20–64 years who completed 24 h dietary recall interviews for both day 1 and day 2 in the National Health and Nutrition Examination Survey (NHANES) 2003–2004, 2005–2006, 2007–2008 and 2009–2010.

Fast-food and full-service restaurant consumption, respectively, was associated with an increase in daily total energy intake of 813·75 kJ (194·49 kcal) and 858·04 kJ (205·21 kcal) and with higher intakes of saturated fat (3·48 g and 2·52 g) and Na (296·38 mg and 451·06 mg). Individual characteristics moderated the impacts of restaurant food consumption with adverse impacts on net energy intake being larger for black adults compared with their white and Hispanic counterparts and greater for middle-income v. high-income adults.

Adults’ fast-food and full-service restaurant consumption was associated with higher daily total energy intake and poorer dietary indicators.

To evaluate longitudinally the effectiveness of a cooking programme on self-reported confidence about cooking skills and food consumption patterns in parents of young children.

An evaluation of cooking programmes delivered by National Health Service (NHS) community food workers using a single group pre-test/post-test repeated measures design. A shortened version of a validated questionnaire at baseline, post intervention and 1-year follow-up determined confidence in cooking using basic ingredients, following a simple recipe, tasting new foods, preparing and cooking new foods on consumption of ready meals, vegetables and fruit.

Deprived communities in Ayrshire and Arran, Scotland.

Parents of nursery age children, 97 % were female and <45 years old.

One hundred and two participants had completed baseline and post-intervention questionnaires. Forty-four participants contacted by telephone completed a follow-up questionnaire. In participants who completed all questionnaires (n 44), median confidence in four aspects of cooking increased significantly from baseline to post intervention (P < 0·001) but was retained at 1-year follow-up only for following a simple recipe and preparing and cooking new foods. Improved food consumption patterns were reported from baseline to post intervention (ready-meal consumption reduced from 2-4 times/week to 1 time/week, P < 0·001; vegetable consumption increased from 5–6 times/week to 1 time/d, P < 0·001; fruit consumption increased from 5–6 times/week to 1 time/d, P < 0·001) and remained at 1-year follow-up.

The cooking programmes appeared to improve cooking confidence and food consumption patterns in the target group and some of these changes were retained after 1 year.

To develop and validate an electronic FFQ that estimates the food and nutrient intakes, especially fat intake, in a healthy, adult population from the coastal (Mediterranean) part of Slovenia.

A new electronic FFQ was developed for a survey entitled ‘A multidisciplinary approach in the treatment of obesity’, conducted at the University of Primorska, and validated against a 3 d weighed food record (FR).

Coastal region of Slovenia.

Our study population included eighty-five healthy adults aged 25–49 years, recruited from the local coastal region of Slovenia. Intakes of food groups, macronutrients and energy, estimated by the FR and the FFQ, were compared using correlation coefficients, cross-classification and Bland–Altman plots.

The mean value of most nutrient intakes tended to be higher in the FFQ compared with the FR, except for carbohydrate, fibre and energy. Regression analysis demonstrated an acceptable agreement between the FFQ and FR. The FFQ was moderately correlated with the FR (0·30–0·54), and most of the correlations increased after energy adjustment and after de-attenuation. Relatively high (more than 70 %) proportions of participants were correctly classified into the same or an adjacent quartile. Bland–Altman analysis confirmed an acceptable level of agreement between the two methods.

The electronic FFQ, developed for a healthy adult Slovene population from the coastal region, was shown to be a valid tool to assess food group and nutrient intakes, especially fat intakes, and to rank individuals by their intakes within gene–nutrient studies.

To (i) evaluate food choices and consumption patterns of elementary- and middle-school students who participate in the National School Lunch Program (NSLP) and (ii) compare students’ average nutrient intake from lunch with NSLP standards.

Plate waste from elementary- and middle-school students’ lunch trays was measured in autumn 2010 using a previously validated digital photography method. Percentage waste was estimated to the nearest 10 % for the entrée, canned fruit, fresh fruit, vegetable, grain and milk. Univariate ANOVA determined differences in percentage waste between schools, grades and genders. Daily nutrient intake was calculated using the district's menu analysis and percentage waste.

Elementary and middle schools in northern Colorado (USA).

Students, grades 1–8.

Plate waste was estimated from 899 lunch trays; 535 elementary- and 364 middle-school students. Only 45 % of elementary- and 34 % middle-school students selected a vegetable. Elementary-school students wasted more than a third of grain, fruit and vegetable menu items. Middle-school students left nearly 50 % of fresh fruit, 37 % of canned fruit and nearly a third of vegetables unconsumed. Less than half of the students met the national meal standards for vitamins A and C, or Fe.

Few students’ lunch consumption met previous or new, strengthened NSLP lunch standards. Due to the relatively low intake of vegetables, intakes of vitamins A and C were of particular concern. Effective behavioural interventions, combined with marketing, communications and behavioural economics, will likely be necessary to encourage increased vegetable intake to meet the new meal standards.

To examine whether home availability of energy-dense snack foods mediates the association between television (TV) viewing and energy-dense snack consumption among adolescents.

Cross-sectional.

Secondary schools in Victoria, Australia.

Adolescents (n 2984) from Years 7 and 9 of secondary school completed a web-based survey, between September 2004 and July 2005, assessing their energy-dense snack food consumption, school-day and weekend-day TV viewing and home availability of energy-dense snack foods.

School-day and weekend-day TV viewing were positively associated with energy-dense snack consumption among adolescent boys (β = 0·003, P < 0·001) and girls (β = 0·03, P < 0·001). Furthermore, TV viewing (school day and weekend day) were positively associated with home availability of energy-dense snack foods among adolescent boys and girls and home availability of energy-dense snack foods was positively associated with energy-dense snack food consumption among boys (β = 0·26, P < 0·001) and girls (β = 0·28, P < 0·001). Home availability partly mediated the association between TV viewing and energy-dense snack consumption.

The results of the present study suggest that TV viewing has a significant role to play in adolescent unhealthy eating behaviours. Future research should assess the efficacy of methods to reduce adolescent energy-dense snack food consumption by targeting parents to reduce home availability of energy-dense foods and by reducing TV viewing behaviours of adolescents.

To document the prevalence of dieting and to compare body composition markers, dietary intakes and eating behaviours across dieting categories.

Prospective, cross-sectional study.

Twenty-four randomly selected secondary public schools located in Attica, Greece.

Anthropometric, medical and dietary information was obtained from 857 (54·9 % females) adolescents (mean age 13·4 (sd 0·9) years). Meal patterns, eating behaviours and eating style score, reflecting conditions around eating, were assessed. Adolescents were asked about their dieting involvement and were categorised as ‘never dieters’, ‘current dieters’ or ‘past dieters’.

Overall, 20·1 % of the adolescents were currently dieting and 15·2 % reported past dieting. Mean BMI and body fat percentage of never dieters were significantly lower than those of both groups of dieters (P < 0·001). Breakfast skipping (χ2 = 10·92, P = 0·004) and eating large quantities of food (χ2 = 7·18, P = 0·028) differed significantly across dieting groups in females. Significant differences in dinner skipping were observed in both males (χ2 = 10·55, P = 0·005) and females (χ2 = 20·91, P < 0·001). Female past dieters had significantly higher eating style scores than never dieters (P = 0·010) and current dieters (P = 0·042), indicating less well-structured feeding practices and food intake for reasons other than hunger.

The present study showed a high prevalence of dieting among adolescents. Current dieters and past dieters had higher BMI and body fat percentage than never dieters. Eating behaviours differed significantly depending on dieting involvement, especially in females; while an apparently healthier, ordered eating style adopted by dieters during the dieting period seemed not to be maintained in the long term.

Due to rising rates of obesity globally, the present study aimed to examine differences in overweight and underweight prevalence in Western Australian schoolchildren in 2008 compared with 2003.

Cross-sectional study at two time points; using two-stage stratified sampling, primary and secondary schools in both metropolitan and non-metropolitan Western Australia; sample selected was representative of the State's population figures.

Seventeen primary and thirteen secondary (2008) and nineteen primary and seventeen secondary (2003) schools. Government and non-government funded schools in metropolitan and non-metropolitan (regional/rural) Western Australia were recruited.

Height and weight were measured for 1708 (961 primary and 747 secondary) students in 2008 and 1694 (876 primary and 817 secondary) students in 2003.

Overweight and obesity prevalence in primary students was similar in 2008 (22·9 %) to 2003 (23·2 %; P > 0·05). In secondary girls overweight and obesity prevalence dropped from 23·1 % (2003) to 15·9 % (2008; P = 0·002). Secondary boys showed a slight decrease in overweight and obesity prevalence; however, this was not statistically significant (P = 0·102). Higher proportions of underweight in primary girls were observed in 2008 (9·9 %) compared with 2003 (4·2 %; P < 0·001) and in secondary girls in 2008 (9·4 %) compared with 2003 (5·5 %; P < 0·001).

Prevalence of overweight and obesity in Western Australian primary students was stable; however, it declined in secondary students. Both primary and secondary girls showed an increase in underweight prevalence. Public health interventions are needed for the high percentage of youth still overweight, whereas the observed increase in underweight girls warrants attention and further investigation.