Childhood fish oil supplementation modifies associations between traffic related air pollution and allergic sensitisation.

BACKGROUND: Studies of potential adverse effects of traffic related air pollution (TRAP) on allergic disease have had mixed findings. Nutritional studies to examine whether fish oil supplementation may protect against development of allergic disease through their anti-inflammatory actions have also had mixed findings. Extremely few studies to date have considered whether air pollution and dietary factors such as fish oil intake may interact, which was the rationale for this study. METHODS: We conducted a secondary analysis of the Childhood Asthma Prevention Study (CAPS) birth cohort, where children were randomised to fish oil supplementation or placebo from early life to age 5 years. We examined interactions between supplementation and TRAP (using weighted road density at place of residence as our measure of traffic related air pollution exposure) with allergic disease and lung function outcomes at age 5 and 8 years. RESULTS: Outcome information was available on approximately 400 children (~ 70% of the original birth cohort). Statistically significant interactions between fish oil supplementation and TRAP were seen for house dust mite (HDM), inhalant and all-allergen skin prick tests (SPTs) and for HDM-specific interleukin-5 response at age 5. Adjusting for relevant confounders, relative risks (RRs) for positive HDM SPT were RR 1.74 (95% CI 1.22-2.48) per 100 m local road or 33.3 m of motorway within 50 m of the home for those randomised to the control group and 1.03 (0.76-1.41) for those randomised to receive the fish oil supplement. The risk differential was highest in an analysis restricted to those who did not change address between ages 5 and 8 years. In this sub-group, supplementation also protected against the effect of traffic exposure on pre-bronchodilator FEV1/FVC ratio. CONCLUSIONS: Results suggest that fish oil supplementation may protect against pro-allergic sensitisation effects of TRAP exposure. Strengths of this analysis are that supplementation was randomised and independent of TRAP exposure, however, findings need to be confirmed in a larger experimental study with the interaction investigated as a primary hypothesis, potentially also exploring epigenetic mechanisms. More generally, studies of adverse health effects of air pollution may benefit from considering potential effect modification by diet and other factors. TRIAL REGISTRATION: Australia New Zealand Clinical Trial Registry. www.anzctr.org.au Registration: ACTRN12605000042640 , Date: 26th July 2005. Retrospectively registered, trial commenced prior to registry availability.

Comparison of Fruit and Vegetable Prices between Farmers' Markets and Supermarkets: Implications for Fruit and Vegetable Incentive Programs for Food Assistance Program Participants.

This cross-sectional study was part of a larger evaluation of a fruit and vegetable (FV) incentive program for Supplemental Nutrition Assistance Program (SNAP) participants in California. We examined the price differences in FV to explore whether these could help explain a previously observed lack of effect of the incentive program on FV consumption. Differences by type (organic/no-spray or conventional), among a convenience sample of farmers' markets (n = 11) and nearby supermarkets (n = 7), were assessed using Wilcoxon rank-sum tests adjusting for clustering by market. We calculated the cost of market baskets comprising recommended FV servings for a household using median prices to consider the implications of FV price differences for SNAP shoppers who use financial incentives for FV. We found that farmers' markets primarily offered organic FV while supermarkets primarily offered conventionally grown FV. Farmers' market prices tended to be lower than supermarkets for organic FV but higher for conventional FV. Compared to supermarkets, the market basket composed only of organic FV cost USD 16.34 less at farmers' markets, whereas a basket comprised of a mix of conventionally and organically grown FV cost USD 3.68 more. These differences warrant further exploration; FV price and type should be considered in studies aimed at understanding the impact of SNAP financial incentive programs.

Community-level obesity prevention is not associated with dieting behaviours and weight dissatisfaction in children: The Healthy Communities Study.

BACKGROUND: Within the context of high childhood obesity prevalence, there is a concern that community efforts intended to reduce childhood obesity may lead to unintended adverse outcomes. OBJECTIVE: This analysis examined relationships between community programs, policies, and environmental changes (CPPs) for obesity prevention with unhealthy dieting behaviours and body weight satisfaction in children. METHODS: Using the Healthy Communities Study 2013 to 2015 survey sample of 5138 US children aged 4 to 15 years old, multilevel models examined associations between standardized CPP intensity scores and child dieting behaviours and weight satisfaction, adjusting for community and child-level covariates and clustered study design. RESULTS: In fully adjusted models, higher total, physical activity, and nutrition CPP intensity scores were associated with lower odds of dissatisfaction with weight (1 year total CPP odds ratio [OR]: 0.41, 95% confidence interval [CI], 0.22-0.73; 6 year total CPP OR: 0.48, 0.29-0.80). Higher physical activity CPP intensity over the past year was associated with greater odds of weight satisfaction (OR: 1.77, 95% CI, 1.10-2.84). No associations were observed with dieting behaviours. CONCLUSIONS: Results suggest that community efforts focusing on nutrition and physical activity to prevent childhood obesity may be associated with weight satisfaction and not with unhealthy dieting behaviours.

Eating School Meals Daily Is Associated with Healthier Dietary Intakes: The Healthy Communities Study.

BACKGROUND: Research on the association between school meal consumption and overall dietary intake post-Healthy Hunger-Free Kids Act implementation is limited. OBJECTIVE: This study examines the association between frequency of participating in the National School Lunch and School Breakfast Programs and children's dietary intakes. DESIGN: The Healthy Communities Study was a cross-sectional observational study conducted between 2013 and 2015. PARTICIPANTS AND SETTING: US children aged 4 to 15 years (n=5,106) were included. MAIN OUTCOME MEASURES: Dietary measures were assessed using the National Health and Nutrition Examination Survey Dietary Screener Questionnaire. Dietary intake included fruit and vegetables, fiber, whole grains, dairy, calcium, total added sugar, sugar-sweetened beverages, and energy-dense foods of minimal nutritional value. STATISTICAL ANALYSIS: Multivariate statistical models assessed associations between frequency of eating school breakfast or lunch (every day vs not every day) and dietary intake, adjusting for child- and community-level covariates. RESULTS: Children who ate school breakfast every day compared with children who ate 0 to 4 days/wk, reported consuming more fruits and vegetables (0.1 cup/day, 95% CI: 0.01, 0.1), dietary fiber (0.4 g/day, 95% CI: 0.2, 0.7), whole grains (0.1 oz/day, 95% CI: 0.05, 0.1), dairy (0.1 cup/day, 95% CI: 0.05, 0.1), and calcium (34.5 mg/day, 95% CI: 19.1, 49.9). Children who ate school lunch every day, compared with those who ate less frequently, consumed more dairy (0.1 cup/day, 95% CI: 0.1, 0.2) and calcium (32.4 mg/day, 95% CI: 18.1, 46.6). No significant associations were observed between school meal consumption and energy-dense nutrient-poor foods or added sugars. CONCLUSIONS: Eating school breakfast and school lunch every day by US schoolchildren was associated with modestly healthier dietary intakes. These findings suggest potential nutritional benefits of regularly consuming school meals.

School Wellness Committees Are Associated With Lower Body Mass Index Z-Scores and Improved Dietary Intakes in US Children: The Healthy Communities Study.

BACKGROUND: Our objective was to examine the association between school wellness committees and implementation of nutrition wellness policies and children's weight status and obesity-related dietary outcomes. METHODS: A cross-sectional study was conducted of 4790 children aged 4-15 years recruited from 130 communities in the Healthy Communities Study. Multilevel statistical models assessed associations between school wellness policies and anthropometric (body mass index z-score [BMIz]) and nutrition measures, adjusting for child and community-level covariates. RESULTS: Children had lower BMI z-scores (-0.11, 95% confidence interval [CI]: -0.19, -0.03) and ate breakfast more frequently (0.14 days/week, 95% CI: 0.02-0.25) if attending a school with a wellness committee that met once or more in the past year compared to attending a school with a wellness committee that did not meet/did not exist. Children had lower added sugar (p < .0001), lower energy-dense foods (p = .0004), lower sugar intake from sugar-sweetened beverages (p = .0002), and lower dairy consumption (p = .001) if attending a school with similar or stronger implementation of the nutrition components of the school wellness policies compared to other schools in the district. CONCLUSIONS: A more active wellness committee was associated with lower BMI z-scores in US schoolchildren. Active school engagement in wellness policy implementation appears to play a positive role in efforts to reduce childhood obesity.

Prevalence of low serum folate and vitamin B12 in an older Australian population.

OBJECTIVE: To examine the prevalence of low serum folate and vitamin B12, in association with elevated serum homocysteine, in a representative sample of older Australians. METHODS: During 1997-2000, 3,508 persons aged 50+ years were examined in a population-based cohort study conducted in two postcodes, west of Sydney, Australia. Of these, 2,901 participants (82.7%) provided fasting blood for estimates of serum folate, vitamin B12 and total homocysteine. RESULTS: Low serum B12 (< 185 pmol/L) was found in 22.9% of participants and low serum folate (< 6.8 nmol/L) in 2.3% of participants. Among those people with very low serum vitamin B12 (< 125 pmol/L) and low serum folate, 51% had elevated homocysteine. CONCLUSIONS: Low serum levels of vitamin B12 and elevated serum homocysteine are relatively frequent in older Australians. IMPLICATIONS: Appropriate public health action should be considered to reduce the prevalence of low serum vitamin B12 and elevated homocysteine in older Australians.

Increasing Child Fruit and Vegetable Intake: Findings from the US Department of Agriculture Fresh Fruit and Vegetable Program.

BACKGROUND: Fewer than 10% of US children and adolescents consume the recommended amounts of fruits and vegetables (F/V). The US Department of Agriculture's Fresh Fruit and Vegetable Program (FFVP) is intended to increase child F/V consumption by funding low-income schools to distribute free fresh F/V snacks outside of school mealtimes. OBJECTIVE: The evaluation assessed FFVP effects on student F/V consumption and total energy intake in and out of school. DESIGN: The evaluation employed a regression discontinuity design; that is, cross-sectional comparisons of a sample of students in schools just above and just below the FFVP funding cutoff for the program, which depended on the proportion of students eligible for free or reduced-price meals. During the 2010-2011 school year within a randomly selected sample of states, we selected schools in closest proximity to each state-specific FFVP funding cutoff. Interviewers conducted 24-hour diary-assisted recall interviews to assess dietary intake among children in selected schools. PARTICIPANTS/SETTING: Participants were 4,696 students (grades 4 to 6) from 214 elementary schools in 16 randomly selected states. STATISTICAL ANALYSES PERFORMED: Analysis proceeded via multivariate regression, comparing adjusted mean student intake in schools just above and just below the funding cutoff. RESULTS: Adjusted mean daily F/V intake was one-third of a cup per day higher in FFVP-participating schools than in nonparticipating schools (0.32 cups per day; P<0.001), a difference of 15.5%. This included one-quarter cup higher daily F/V intake during school hours (0.26 cups; P<0.001) among students attending FFVP-participating schools. Fresh (but not total) F/V consumption also increased outside of school. CONCLUSIONS: The FFVP increases child fresh and total F/V intake in school, and fresh F/V intake outside of school.

The Healthy Communities Study Nutrition Assessments: Child Diet and the School Nutrition Environment.

Multifaceted community interventions directed at improving food environments are emerging, but their impact on dietary change and obesity prevalence has not been adequately documented. The Healthy Communities Study (HCS) is seeking to identify characteristics and combinations of programs and policies that are associated with children's diets and obesity-related outcomes in various types of communities across the U.S. The purpose of this paper is to describe the methods used in 2013-2015 in the HCS to assess dietary intake, school nutrition environments, and other nutrition-related behaviors. The conceptual framework of the HCS is based on the socioecological model and behaviors shown in previous studies to be related to obesity in children guided selection of domains. Nine domains were identified as essential measures of nutrition in the HCS: (1) intake of selected foods and beverages; (2) food patterns and behaviors; (3) social support; (4) home environment; (5) school environment; (6) community environment; (7) breastfeeding history; (8) household food insecurity; and (9) dieting behaviors and body image. Children's dietary intake was assessed using a dietary screener and up to two automated 24-hour recalls. Dietary-related behaviors were assessed by a survey administered to the parent, child, or both, depending on child age. School nutrition measures were obtained from a combination of school staff surveys and researcher observations. Information from these measures is expected to contribute to a better understanding of "what is working" to improve the dietary behaviors that are likely to prevent obesity and improve health in children.

Body mass index (BMI) trajectories from birth to 11.5 years: relation to early life food intake.

Recent research has shown that the pattern of change over time, or trajectory, of body mass index (BMI) varies among children. However, the factors that underlie the heterogeneity in these trajectories remain largely unexplored. Our aim was to use a growth mixture model to empirically identify classes of BMI trajectories (from birth to 11.5 years) and examine the effects of breastfeeding, introduction of solids, as well as food and nutrient intake at 18 months on these BMI trajectories. We identified three BMI growth trajectories between birth and age 11.5 years, separately in boys and girls. Breastfeeding duration less than six months and the early introduction of solids did not adversely influence BMI trajectories in our sample but high intakes of meat, particularly high fat varieties, and high intakes of carbohydrate at age around 18 months were associated with a high BMI trajectory in boys. It is not clear whether these dietary factors confer a direct risk of higher BMI in childhood or are markers for other dietary patterns that are present early and/or develop through childhood and contribute to higher BMI.

Effect of omega 3 and omega 6 fatty acid intakes from diet and supplements on plasma fatty acid levels in the first 3 years of life.

BACKGROUND: The optimal method for conducting omega (n-)3 polyunsaturated fatty acid (PUFA) supplementation trials in children is unknown. AIM: To assess the impact of n-3 and n-6 PUFA intake from the background diet on plasma levels of n-3 and n-6 PUFA in children aged 0-3 years, with and without n-3 supplementation. METHODS: Subjects were randomised antenatally to receive either n-3 PUFA supplements and low n-6 PUFA cooking oils and spreads or a control intervention, designed to maintain usual fatty acid intake. Dietary intake was assessed at 18 months by 3-day weighed food record and at 3 years by food frequency questionnaire. Plasma phospholipids were measured at both time points. Associations were tested by regression. RESULTS: N-3 PUFA intake from background diet did not significantly affect plasma n-3 levels. In contrast, n-6 PUFA intake in background diet was positively related to plasma n-6 levels in both study groups. In addition, n-6 PUFA intake from diet was negatively associated with plasma n-3 levels at 18 months and 3 years (-0.16%/g n-6 intake, 95%CI -0.29 to -0.03 and -0.05%/g n-6 intake, 95%CI -0.09 to -0.01, respectively) in the active group, but not in the control group. CONCLUSION: Interventions intending to increase plasma n-3 PUFA in children by n-3 supplementation should also minimise n-6 PUFA intake in the background diet.

Fatty acid intakes and food sources in a population of older Australians.

OBJECTIVE: To document dietary intakes and food sources of fatty acids among older Australians. DESIGN: Population-based survivor cohort. SETTING: Two postcode areas in the Blue Mountains, West of Sydney, Australia. SUBJECTS: In 1997-9, 2334 people aged 55 years and over, participated in a 5-year follow-up of the cohort attending the Blue Mountains Eye Study (BMES). Dietary data were collected using a semi-quantitative food frequency questionnaire by 2005 persons (86% of those examined). Types of fats were classified as saturated fatty acids (SFA), monounsaturated (MUFA), polyunsaturated (PUFA) and trans unsaturated fatty acids. RESULTS: Mean total fat intake contributed 31.3% of daily energy intake (12.2% SFA, 11.2% MUFA, 5.0% PUFA). Mean omega 3 (n-3) PUFA intake comprised 0.5% of energy intake (long chain n-3 PUFA provided mean intake of 260mg, consisting of eicosapentaenoic (EPA), docosapentaenoic (DPA) and docosahexaenoic (DHA) fatty acids) and the n-6: n-3 PUFA ratio was 9:1. The main fatty acids contributing to the diet were palmitic acid, oleic acid and linoleic acid. Meat products were the highest contributors to total fat and MUFA intakes; milk products were the highest contributor to SFA intakes; and fat spreads and oils, and breads and cereals were the main food groups contributing to PUFA intakes. Fish was the main source of long chain n-3 fatty acids. CONCLUSIONS: This population-based descriptive study documents fatty acid intakes in a population of older Australians. It will serve as a basis for investigations of associations between dietary fatty acid intakes and a number of eye diseases.

The weight of evidence suggests that soft drinks are a major issue in childhood and adolescent obesity.

There is much to be gained by reducing children's intake of soft drinks and little - except excess weight - to be lost.

Consumption of 'extra' foods (energy-dense, nutrient-poor) among children aged 16-24 months from western Sydney, Australia.

OBJECTIVE: This study evaluates the contribution of energy-dense, nutrient-poor 'extra' foods to the diets of 16-24-month-old children from western Sydney, Australia. DESIGN: An analysis of cross-sectional data collected on participants in the Childhood Asthma Prevention Study (CAPS), a randomised trial investigating the primary prevention of asthma from birth to 5 years. We collected 3-day weighed food records, calculated nutrient intakes, classified recorded foods into major food groups, and further classified foods as either 'core' or 'extras' according to the Australian Guide to Healthy Eating. SETTING: Pregnant women, whose unborn child was at risk of developing asthma because of a family history, were recruited from all six hospitals in western Sydney, Australia. Data for this study were collected in clinic visits and at participants' homes at the 18-month assessment. PARTICIPANTS: Four hundred and twenty-nine children participating in the CAPS study; 80% of the total cohort. RESULTS: The mean consumption of 'extra' foods was approximately 150 g day(-1) and contributed 25-30% of the total energy, fat, carbohydrate and sodium to the diets of the study children. 'Extra' foods also contributed around 20% of fibre, 10% of protein and zinc, and about 5% of calcium. Children in the highest quintile of 'extra' foods intake had a slightly higher but not significantly different intake of energy from those in the lowest quintile. However, significant differences were evident for the percentage of energy provided by carbohydrate and sugars (higher) and protein and saturated fat (lower). The intake of most micronutrients was also significantly lower among children in the highest quintile of consumption. The intake of 'extra' foods was inversely associated with the intake of core foods. CONCLUSIONS: The high percentage of energy contributed by 'extra' foods and their negative association with nutrient density emphasise the need for dietary guidance for parents of children aged 1-2 years. These preliminary data on commonly consumed 'extra' foods and portion sizes may inform age-specific dietary assessment methods.

Issues in assessing the validity of nutrient data obtained from a food-frequency questionnaire: folate and vitamin B12 examples.

OBJECTIVE: To compare methods used to assess the validity of nutrient intake data obtained from a food-frequency questionnaire (FFQ), using folate and vitamin B12 as nutrient examples. DESIGN: Cross-sectional sample from a population cohort. SETTING: Two postcode areas west of Sydney, Australia. SUBJECTS: In total, 2895 people aged 49 years and older provided dietary data using a semi-quantitative FFQ (79% of 3654 subjects examined). The validity of the FFQ was assessed against three 4-day weighed food records (WFRs) completed by 78 people (mean age 70 years). RESULTS: Folate and vitamin B12 validity data were assessed using different methods. The Spearman ranked correlations (energy-adjusted) were 0.66 for folate and 0.38 for vitamin B12. Using the Bland-Altman method, following loge transformation, no linear trend existed between the differences and means for folate and vitamin B12. Large differences existed between the FFQ and WFR in individual cases, particularly for vitamin B12. Finally, data were divided into quintile categories for the test and reference method: 79% classified folate within one quintile, 65% classified vitamin B12 within one quintile; there was no gross misclassification for folate and only 3% misclassification for vitamin B12. CONCLUSIONS: Different methods of analysis provided different information about the validity of the FFQ. Correlation coefficients should not be used alone to assess the validity of nutrient data, but should be used in conjunction with Bland-Altman analyses. Depending on the use of the data, additional assessment of classification categories is recommended. This worked example demonstrates that absolute intakes of folate and vitamin B12 should be used with caution.