School free fruit and vegetable (FFV) policies are used to promote healthy dietary habits and tackle obesity; however, our understanding of their effects on weight outcomes is limited. We assess the ...effect of a nationwide FFV policy on childhood and adolescent weight status and explore heterogeneity by sex and socioeconomic position.
This study used a quasi-natural experimental design. Between 2007 and 2014, Norwegian combined schools (grades 1-10, age 6 to 16 years) were obligated to provide FFVs while elementary schools (grades 1-7) were not. We used 4 nationwide studies (n = 11,215 children) from the Norwegian Growth Cohort with longitudinal or cross-sectional anthropometric data up to age 8.5 and 13 years to capture variation in FFV exposure. Outcomes were body mass index standard deviation score (BMISDS), overweight and obesity (OW/OB), waist circumference (WC), and weight to height ratio (WtHR) at age 8.5 years, and BMISDS and OW/OB at age 13 years. Analyses included longitudinal models of the pre- and post-exposure trajectories to estimate the policy effect. The participation rate in each cohort was >80%, and in most analyses <4% were excluded due to missing data. Estimates were adjusted for region, population density, and parental education. In pooled models additionally adjusted for pre-exposure BMISDS, there was little evidence of any benefit or unintended consequence from 1-2.5 years of exposure to the FFV policy on BMISDS, OW/OB, WC, or WtHR in either sex. For example, boys exposed to the FFV policy had a 0.05 higher BMISDS (95% CI: -0.04, 0.14), a 1.20-fold higher odds of OW/OB (95% CI: 0.86, 1.66) and a 0.3 cm bigger WC (95% CI: -0.3, 0.8); while exposed girls had a 0.04 higher BMISDS (95% CI: -0.04, 0.13), a 1.03 fold higher odds of OW/OB (95% CI: 0.75, 1.39), and a 0-cm difference in WC (95% CI: -0.6, 0.6). There was evidence of heterogeneity in the policy effect estimates at 8.5 years across cohorts and socioeconomic position; however, these results were inconsistent with other comparisons. Analysis at age 13 years, after 4 years of policy exposure, also showed little evidence of an effect on BMISDS or OW/OB. The main limitations of this study are the potential for residual confounding and exposure misclassification, despite efforts to minimize their impact on conclusions.
In this study we observed little evidence that the Norwegian nationwide FFV policy had any notable beneficial effect or unintended consequence on weight status among Norwegian children and adolescents.
Background Studies of the associations between in utero 25-hydroxyvitamin D (25OHD) exposure and risk of childhood asthma, wheeze, and respiratory tract infections are inconsistent and inconclusive. ...Objectives We sought to assess associations between 25(OH)D levels in cord blood or maternal venous blood and risk of offspring's asthma, wheeze, and respiratory tract infections. Methods Data were derived from PubMed, Embase, Google Scholar, references from relevant articles, and de novo results from published studies until December 2015. A random-effects meta-analysis was conducted among 16 birth cohort studies. Results Comparing the highest with the lowest category of 25(OH)D levels, the pooled odds ratios were 0.84 (95% CI, 0.70-1.01; P = .064) for asthma, 0.77 (95% CI, 0.58-1.03; P = .083) for wheeze, and 0.85 (95% CI, 0.66-1.09; P = .187) for respiratory tract infections. The observed inverse association for wheeze was more pronounced and became statistically significant in the studies that measured 25(OH)D levels in cord blood (0.43; 95% CI, 0.29-0.62; P < .001). Conclusions Accumulated evidence generated from this meta-analysis suggests that increased in utero exposure to 25(OH)D is inversely associated with the risk of asthma and wheeze during childhood. These findings are in keeping with the results of 2 recently published randomized clinical trials of vitamin D supplementation during pregnancy.
Much of our understanding of the age-related progression of systolic blood pressure (SBP) comes from cross-sectional data, which do not directly capture within-individual change. We estimated life ...course trajectories of SBP using longitudinal data from seven population-based cohorts and one predominantly white collar occupational cohort, each from the United Kingdom and with data covering different but overlapping age periods.
Data are from 30,372 individuals and comprise 102,583 SBP observations spanning from age 7 to 80+y. Multilevel models were fitted to each cohort. Four life course phases were evident in both sexes: a rapid increase in SBP coinciding with peak adolescent growth, a more gentle increase in early adulthood, a midlife acceleration beginning in the fourth decade, and a period of deceleration in late adulthood where increases in SBP slowed and SBP eventually declined. These phases were still present, although at lower levels, after adjusting for increases in body mass index though adulthood. The deceleration and decline in old age was less evident after excluding individuals who had taken antihypertensive medication. Compared to the population-based cohorts, the occupational cohort had a lower mean SBP, a shallower annual increase in midlife, and a later midlife acceleration. The maximum sex difference was found at age 26 (+8.2 mm Hg higher in men, 95% CI: 6.7, 9.8); women then experienced steeper rises and caught up by the seventh decade.
Our investigation shows a general pattern of SBP progression from childhood in the UK, and suggests possible differences in this pattern during adulthood between a general population and an occupational population. Please see later in the article for the Editors' Summary.
Fat and lean body mass have important implications for health and physical functioning in older age, and physical activity is purported to be an important modifiable determinant. However, our ...evidence-based understanding of its role is limited. We examined the associations of physical activity, assessed both by self-report (using data on leisure time physical activity (LTPA) collected on 4 occasions over a 28-year period) and objectively (using 5-day heart rate and movement monitoring), with fat and lean mass at ages 60–64 years in 1,162 British participants from the Medical Research Council National Survey of Health and Development in 1946–2010. Higher objectively assessed physical activity energy expenditure (PAEE) at ages 60–64 years was associated with lower fat mass and android (abdominal):gynoid (hip) fat ratio (mean differences in fat mass per 1–standard deviation increase in PAEE were −0.79 kg/m1.2 in men (95% confidence interval: −1.08, −0.50) and −1.79 kg/m1.2 (95% confidence interval: −2.15, −1.42) in women). After adjustment for fat mass, higher PAEE was associated with higher appendicular lean mass. Both light and moderate-to-vigorous intensities of activity were associated with fat mass, and the latter was associated with lean mass. More frequent LTPA across adulthood was associated with lower fat mass (in women only) and higher appendicular lean mass (in both sexes, after adjustment for fat mass). These results support the promotion of LTPA across adulthood, as well as both light and moderate-to-vigorous intensities of activity among older adults.
To estimate the prevalence of overweight, obesity, and thinness among Norwegian 13-year-olds and the changes from childhood (age 8 years) to adolescence (age 13 years); and to explore associations ...with sex, region, and population density from childhood to adolescence.
We used longitudinal, anthropometric data collected by school health nurses conducted in Norway. Weight status was classified according to the International Obesity Task Force cut-offs for overweight, obesity, and thinness, and according to mean body mass index (kg/m2).
The Norwegian Youth Growth Study, consisting of a nationally representative sample of Norwegian 13-year-olds (n = 1852; 50.7% girls), which is a part of The Norwegian Growth Cohort.
Among 13-year-old Norwegians, the prevalence of overweight (including obesity), obesity, and thinness was 15.8%, 2.5%, and 7.3%, respectively. There was little evidence that these had changed from 8 to 13 years. From 8 to 13 years, the odds of obesity was highest in the Northern region of Norway compared to the South-East (odds ratio (OR): 3.78 (95% confidence interval (CI): 1.13, 12.65; p = 0.036) and in rural areas (OR: 4.76 (95% CI: 1.52, 14.90; p = 0.027). Over the same age period, girls had a trend towards a higher odds of thinness compared to boys (OR: 1.65 (95% CI: 0.98, 2.78; p = 0.057).
In Norway, the prevalence of overweight, obesity, and thinness among 13-year-olds seem to be established by age 8 years. The prevalence of obesity was higher in the North and in rural areas. The results indicate the continued need for early prevention and treatment, and targeted interventions to certain areas.
The Norwegian randomized controlled trial Early Food for Future Health provided parental anticipatory guidance on early protective feeding practices from child age 6 to 12 months through an eHealth ...intervention. Previously published outcomes at child age 12 months indicated that the eHealth intervention increased daily vegetable/fruit intake and promoted more beneficial mealtime routines. The objective of the current paper is to evaluate the effects of the intervention at child age 24 months, one year after cessation.
Parents of infants aged 3-5 months were recruited via social media and child health clinics during spring 2016. At child age 5.5 months, 715 mothers were randomized to either control (n = 358) or intervention (n = 360) arm. Primary study-outcomes were child eating behaviors, dietary intake, mealtime routines and maternal feeding practices and feeding styles. Secondary outcome was child anthropometry.
In total 295 mothers (41%) completed the follow-up questionnaire at child age 24 months. Regarding fruit intake, 54.3% in the intervention group had a high score compared with 48.3% of the control group (p = 0.29). For intake of vegetables, 54.5% in the intervention group had a high score compared with 50.7% in the control group (p = 0.49). A total of 65.7% of the children in the intervention group were eating breakfast together with family ≥ 4 times per week, compared with 57.3% of the children in the control group (p = 0.12). There was no difference between the groups for child anthropometric outcomes at child age 24 months.
At child age 24 months, we found no evidence of sustained intervention-effects. Although dietary patterns and mealtime routines at child age 24 months were reasonably consistent and in the same directions as at child age 12 months, the between-group differences were not significant. The large loss to follow-up may have limited power and validity and makes it difficult to draw overall conclusions. Future research is needed to improve knowledge of how short-time effects could be retained over longer term, taking into account that larger samples are necessary when planning longer-term follow-up studies.
ISRCTN, ISRCTN13601567.
Strategies to optimize early-life nutrition provide an important opportunity for primary prevention of childhood obesity. Interventions that can be efficiently scaled-up to the magnitude needed for ...sustainable childhood obesity prevention are needed. The objective of this study was to evaluate the effects of an eHealth intervention on parental feeding practices and infant eating behaviors.
The Norwegian study Early Food for Future Health is a randomized controlled trial. Parents were recruited via social media and child health clinics during spring 2016 when their child was aged 3 to 5 months. In total 718 parents completed a web-based baseline questionnaire at child age 5.5 months. The intervention group had access to a webpage with monthly short video clips addressing specific infant feeding topics and age-appropriate baby food recipes from child age 6 to 12 months. The control group received routine care. The primary outcomes were child eating behaviors, dietary intake, mealtime routines and maternal feeding practices and feeding styles. The secondary outcomes were child anthropometry. This paper reports outcomes at child age 12 months.
More than 80% of the intervention group reported viewing all/most of the video clips addressing infant feeding topics and indicated that the films were well adapted to the child's age and easy to understand. Children in the intervention group were served vegetables/fruits more frequently (p = 0.035) and had tasted a wider variety of vegetables (p = 0.015) compared to controls. They were also more likely to eat family breakfast (p = 0.035) and dinner (p = 0.011) and less likely to be playing or watching TV/tablet during meals (p = 0.009) compared to control-group children. We found no group differences for child anthropometry or maternal feeding practices.
Our findings suggest that the eHealth intervention is an appropriate and feasible tool to propagate information on healthy infant feeding to Norwegian mothers. Our study also suggests that anticipatory guidance on early protective feeding practices by such a tool may increase young children's daily vegetable/fruit intake and promote beneficial mealtime routines.
ISRCTN, ISRCTN13601567. Registered 29 February 2016, http://www.isrctn.com/ISRCTN13601567.
The timing of associations between common genetic variants for weight or body mass index (BMI) across the life course may provide insights into the aetiology of obesity. We genotyped variants in FTO ...(rs9939609) and near MC4R (rs17782313) in 1240 men and 1239 women born in 1946 and participating in the MRC National Survey of Health and Development. Birth weight was recorded and height and weight were measured or self-reported repeatedly at 11 time-points between ages 2 and 53 years. Hierarchical mixed models were used to test whether genetic associations with weight or BMI standard deviation scores (SDS) changed with age during childhood and adolescence (2–20 years) or adulthood (20–53 years). The association between FTO rs9939609 and BMI SDS strengthened during childhood and adolescence (rate of change: 0.007 SDS/A-allele/year; 95% CI: 0.003–0.010, P < 0.001), reached a peak strength at age 20 years (0.13 SDS/A-allele, 0.08–0.19), and then weakened during adulthood (−0.003 SDS/A-allele/year, −0.005 to −0.001, P = 0.001). MC4R rs17782313 showed stronger associations with weight than BMI; its association with weight strengthened during childhood and adolescence (0.005 SDS/C-allele/year; 0.001–0.008, P = 0.006), peaked at age 20 years (0.13 SDS/C-allele, 0.07–0.18), and weakened during adulthood (−0.002 SDS/C-allele/year, −0.004 to 0.000, P = 0.05). In conclusion, genetic variants in FTO and MC4R showed similar biphasic changes in their associations with BMI and weight, respectively, strengthening during childhood up to age 20 years and then weakening with increasing adult age. Studies of the aetiology of obesity spanning different age groups may identify age-specific determinants of weight gain.
Background: Low birth weight (LBW) is an important public health problem in undernourished populations.Objective: We tested whether improving women's dietary micronutrient quality before conception ...and throughout pregnancy increases birth weight in a high-risk Indian population.Design: The study was a nonblinded, individually randomized controlled trial. The intervention was a daily snack made from green leafy vegetables, fruit, and milk (treatment group) or low-micronutrient vegetables (potato and onion) (control group) from ≥90 d before pregnancy until delivery in addition to the usual diet. Treatment snacks contained 0.69 MJ of energy (controls: 0.37 MJ) and 10–23% of WHO Reference Nutrient Intakes of β-carotene, riboflavin, folate, vitamin B-12, calcium, and iron (controls: 0–7%). The primary outcome was birth weight.Results: Of 6513 women randomly assigned, 2291 women became pregnant, 1962 women delivered live singleton newborns, and 1360 newborns were measured. In an intention-to-treat analysis, there was no overall increase in birth weight in the treatment group (+26 g; 95% CI: −15, 68 g; P = 0.22). There was an interaction (P < 0.001) between the allocation group and maternal prepregnant body mass index (BMI; in kg/m2) birth-weight effect: −23, +34, and +96 g in lowest (<18.6), middle (18.6–21.8), and highest (>21.8) thirds of BMI, respectively. In 1094 newborns whose mothers started supplementation ≥90 d before pregnancy (per-protocol analysis), birth weight was higher in the treatment group (+48 g; 95% CI: 1, 96 g; P = 0.046). Again, the effect increased with maternal BMI (−8, +79, and +113 g; P-interaction = 0.001). There were similar results for LBW (intention-to-treat OR: 0.83; 95% CI: 0.66, 1.05; P = 0.10; per-protocol OR = 0.76; 95% CI: 0.59, 0.98; P = 0.03) but no effect on gestational age in either analysis.Conclusions: A daily snack providing additional green leafy vegetables, fruit, and milk before conception and throughout pregnancy had no overall effect on birth weight. Per-protocol and subgroup analyses indicated a possible increase in birth weight if the mother was supplemented ≥3 mo before conception and was not underweight. This trial was registered at www.controlled-trials.com/isrctn/ as ISRCTN62811278.
The authors examined how body mass index (BMI) across life is linked to the risk of midlife knee osteoarthritis (OA), testing whether prolonged exposure to high BMI or high BMI at a particular period ...has the greatest influence on the risk of knee OA.
A population-based British birth cohort of 3035 men and women underwent clinical examination for knee OA at age 53 years.Heights and weights were measured 10 times from 2 to 53 years. Analyses were stratified by gender and adjusted for occupation and activity levels.
The prevalence of knee OA was higher in women than in men (12.9% (n=194) vs 7.4% (n=108)). In men, the association between BMI and later knee OA was evident at 20 years (p=0.038) and remained until 53 years (OR per z-score 1.38 (95% CI 1.11 to 1.71)). In women, there was evidence for an association at 15 years (p=0.003); at 53 years, the OR was 1.89 (95% CI 1.59 to 2.24) per z-score increase in BMI. Changes in BMI from childhood in women and from adolescence in men were also positively associated with knee OA. A structured modelling approach to disentange the way in which BMI is linked to knee OA suggested that prolonged exposure to high BMI throughout adulthood carried the highest risk and that there was no additional risk conferred from adolescence once adult BMI had been accounted for.
This study suggests that the risk of knee OA accumulates from exposure to a high BMI through adulthood.