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Background: Overweight and obesity among children is a serious public health challenge worldwide which may lead to a range of negative physical, mental, and social consequences in childhood and later in life. There is a strong need for developing new innovative, integrated approaches and programs which can prevent overweight in children effectively and can be embedded into everyday practices. The Generation Healthy Kids intervention is a multi-component, multi-setting intervention aiming to promote healthy weight and well-being in children aged 6–11 years in Denmark. The present study investigates the feasibility and acceptability of 10 selected school-based intervention components and barriers and facilitators for implementation. Methods: A seven-week feasibility study was conducted in January to March 2023 among children in 1st and 2nd grade at a Danish public school, testing the multi-component intervention targeting children’s meal-, physical activity-, sleep- and screen habits. Process evaluation data were collected using multiple methods (surveys, logbooks, evaluation sheets, registrations, counts, interviews, and observations) and data sources (parents, school staff, and school leader). Results: Most intervention components were feasible to deliver at the school, but only four components were fully delivered as intended, while the remaining components to some or low degree were delivered as intended. Some components were found acceptable by all/nearly all children (e.g., 40 min of high intensity training three times a week), and others by some or few children (e.g., reusable water bottles and midmorning snack). Intervention activities for the parents and families were found acceptable by all/nearly all participating parents. Parents’ acceptability of the intervention activities delivered to their children at school could not be assessed, as only few parents participated in surveys and none in interviews. School staff’s acceptability of the intervention tas

Diets, but also overall food environments, comprise a variety of significant factors with direct and indirect impacts on human health. Eco-Regions are geographical areas with a territorial approach to rural development, utilizing organic food and farming practices, and principles and promoting sustainable communities and food systems. However, so far, little attention has been given to quantifying aspects of the health of citizens living in these sustainable transition territories. The project "Indicators for Assessment of Health Effects of Consumption of Sustainable, Organic School Meals in Eco-Regions" (INSUM) aims to identify and discuss research approaches and indicators that could be applied to effectively measure the somatic, mental, and social health dimensions of citizens in Eco-Regions, linked to the intake of organic foods in their diets. In this paper, we focus on the somatic (physical) health dimension. A two-day workshop was held to discuss suitable methodology with an interdisciplinary, international group of experts. The results showed the limitations of commonly used tools for measuring dietary intake (e.g., relying on the memory of participants), and nutritional biomarkers (e.g., variations in correlations with specific intakes) for research understanding dietary intake and the health effects of diets. To investigate the complexity of this issue, the most suitable approach seems to be the combination of traditional markers of physical and mental health alongside emerging indicators such as the microbiome, nutrigenomics, metabolomics, or inflammatory biomarkers. Using new, digital, non-invasive, and wearable technologies to monitor indicators could complement future research. We conclude that future studies should adopt systemic, multidisciplinary approaches by combining not only indicators of somatic and mental health and social wellbeing (MHSW) but also considering the potential benefits of organic diets for health as well as aspects of sustaina

Background: Wholegrain intake is associated with lower risk of cardiometabolic diseases in adults, potentially via changes in the gut microbiota. Although cardiometabolic prevention should start early, we lack evidence on the effects in children. Objectives: This study investigated the effects of wholegrain oats and rye intake on serum low-density lipoprotein (LDL) cholesterol and plasma insulin (coprimary outcomes), other cardiometabolic markers, body composition, gut microbiota composition and metabolites, and gastrointestinal symptoms in children with high body mass index (BMI). Methods: In a randomized crossover trial, 55 healthy Danish 8- to 13-y-olds received wholegrain oats and rye (“WG”) or refined grain (“RG”) products ad libitum for 8 wk in random order. At 0, 8, and 16 wk, we measured anthropometry, body composition by dual-energy absorptiometry, and blood pressure. Fasting blood and fecal samples were collected for analysis of blood lipids, glucose homeostasis markers, gut microbiota, and short-chain fatty acids. Gut symptoms and stool characteristics were determined by questionnaires. Diet was assessed by 4-d dietary records and compliance by plasma alkylresorcinols (ARs). Results: Fifty-two children (95%) with a BMI z-score of 1.5 ± 0.6 (mean ± standard deviation) completed the study. They consumed 108 ± 38 and 3 ± 2 g/d wholegrain in the WG and RG period, which was verified by a profound difference in ARs (P < 0.001). Compared with RG, WG reduced LDL cholesterol by 0.14 (95% confidence interval: −0.24, −0.04) mmol/L (P = 0.009) and reduced total:high-density lipoprotein cholesterol (P < 0.001) and triacylglycerol (P = 0.048) without altering body composition or other cardiometabolic markers. WG also modulated the abundance of specific bacterial taxa, increased plasma acetate, propionate, and butyrate and fecal butyrate and reduced fatigue with no other effects on gut symptoms. Conclusion: High intake of wholegrain oats and rye reduced LDL cho

Optimal growth and development in childhood and adolescence is crucial for lifelong health and well-being1–6. Here we used data from 2,325 population-based studies, with measurements of height and weight from 71 million participants, to report the height and body-mass index (BMI) of children and adolescents aged 5–19 years on the basis of rural and urban place of residence in 200 countries and territories from 1990 to 2020. In 1990, children and adolescents residing in cities were taller than their rural counterparts in all but a few high-income countries. By 2020, the urban height advantage became smaller in most countries, and in many high-income western countries it reversed into a small urban-based disadvantage. The exception was for boys in most countries in sub-Saharan Africa and in some countries in Oceania, south Asia and the region of central Asia, Middle East and north Africa. In these countries, successive cohorts of boys from rural places either did not gain height or possibly became shorter, and hence fell further behind their urban peers. The difference between the age-standardized mean BMI of children in urban and rural areas was <1.1 kg m–2 in the vast majority of countries. Within this small range, BMI increased slightly more in cities than in rural areas, except in south Asia, sub-Saharan Africa and some countries in central and eastern Europe. Our results show that in much of the world, the growth and developmental advantages of living in cities have diminished in the twenty-first century, whereas in much of sub-Saharan Africa they have amplified.

Purpose: Low vitamin D status is a global problem and has been associated with reduced skeletal and cardiometabolic health. However, evidence in young children is lacking. We, therefore, aimed to characterise vitamin D status in toddlers, identify its determinants, and explore if vitamin D status was associated with bone mineralisation and lipid profile. Methods: We used cross-sectional data from 3-year-old children (n=323) living in Denmark (latitude: 55°N). Bone mineralisation (n=108) was measured by DXA. Blood samples were analysed for serum 25-hydroxyvitamin D (s-25(OH)D) by LC–MS/MS, triacylglycerol, and total, low- and high density lipoprotein cholesterol. Results: Mean±SD s-25(OH)D was 69±23 nmol/L, but varied with season. During winter, 38% had inadequate s-25(OH) D (<50 nmol), whereof 15% had deficiency (<30 nmol/L); these numbers were only 7 and 1% during summer. In terms of status determinants, supplement use (66% were users) was associated with s-25(OH)D (P<0.001), whereas dietary vitamin D intake (median [25–75th percentile] of 1.3 [0.9–1.9] µg/d), sex, parental education, BMI, and physical activity were not. There were no associations between s-25(OH)D and blood lipids or bone measurements, using either unadjusted or adjusted regression models. Conclusion: More than 1/3 of Danish toddlers had inadequate vitamin D intake during winter, but acceptable mean vitamin D status. In addition to season, supplement use was the main determinant of vitamin D status, which was, however, not associated with bone mineralisation or lipid profile. The results support recommendations of vitamin D supplements during winter at northern latitudes, but potential health effects need further investigation.

Background: Increasing evidence suggests that prevention of lifestyle diseases should begin early. Dairy protein and vitamin D can affect body composition and cardiometabolic markers, yet evidence among well-nourished children is sparse.Objectives: We investigated combined and separate effects of high dairy protein intake and vitamin D on body composition and cardiometabolic markers in children.Methods: In a 2 × 2-factorial, randomized trial, 200 white, Danish, 6-8-y-old children substituted 260 g/d dairy in their diet with high-protein (HP, 10 g protein/100 g) or normal-protein (NP, 3.5 g protein/100 g) yogurt and received blinded tablets with 20 µg/d vitamin D3 or placebo for 24 weeks during winter. We measured body composition by dual-energy X-ray absorptiometry, blood pressure, and fasting blood glucose, insulin, C-peptide, and lipids.Results: In total, 184 children (92%) completed the study. Baseline median [25th-75th percentile] dairy protein intake was 3.7 [2.5-5.1] E% and increased to 7.2 [4.7-8.8] E% and 4.2 [3.1-5.3] E% with HP and NP. Mean ± SD serum 25-hydroxyvitamin D changed from 81±17 nmol/L to 89±18 nmol/L and 48±13 nmol/L with vitamin D and placebo. There were no combined effects of dairy protein and vitamin D, except for plasma glucose, with the largest increase in the NP-vitamin D group (Pinteraction = 0.005). There were smaller increases in fat mass index (P = 0.04) with HP than NP, and the same pattern was seen for insulin, HOMA-IR, and C-peptide (all P = 0.06). LDL cholesterol was reduced with vitamin D compared to placebo (P < 0.05). Fat free mass and blood pressure were unaffected.Conclusions: High compared to normal dairy protein intake hampered an increase in fat mass index. Vitamin D supplementation counteracted the winter decline in 25-hydroxyvitamin D and the increase in LDL cholesterol observed wit

Purpose: To investigate separate and combined effects of vitamin D supplementation during the extended winter and increased dairy protein intake on muscle strength and physical function in children, and furthermore to explore potential sex differences. Methods: In a 2×2-factorial, randomized winter trial, 183 healthy, 6–8-year-old children received blinded tablets with 20 µg/day vitamin D3 or placebo, and substituted 260 g/day dairy with yogurts with high (HP, 10 g protein/100 g) or normal protein content (NP, 3.5 g protein/100 g) for 24 weeks during winter at 55° N. We measured maximal isometric handgrip and leg press strength, and physical function by jump tests and a 30 s sit-to-stand test. Physical activity was measured by 7-day accelerometry. Results: Baseline (mean±SD) serum 25-hydroxyvitamin D was 80.8±17.2 nmol/L, which increased to 88.7±17.6 nmol/L with vitamin D supplementation and decreased to 48.4±19.2 nmol/L with placebo. Baseline protein intake was 15.5±2.4 E%, which increased to 18.4±3.4 E% with HP and was unchanged with NP. We found no separate or combined effects of vitamin D supplementation and/or increased dairy protein intake on muscle strength or physical function (all P>0.20). There was an interaction on the sit-to-stand test (Pvitamin×yogurt=0.02), which however disappeared after adjusting for physical activity (P=0.16). Further, vitamin D supplementation increased leg press strength relatively more in girls compared to boys (mean [95% CI] 158 [17, 299] N; Pvitamin×sex=0.047). Conclusion: Overall, vitamin D and dairy protein supplementation during the extended winter did not affect muscle strength or physical function in healthy children. Potential sex differences of vitamin D supplementation should be investigated further. Registered at clinicaltrials.gov: NCT0395673.

Purpose: Wholegrain intake is linked to lower risk of lifestyle diseases, but little is known about its role in growth and metabolic health during the first years of life. We characterized wholegrain and dietary fibre intake in 439 Danish children at 9 and 36 months of age and explored associations with height z-scores (HAZ), body mass index z-scores (BMIZ) and metabolic markers.Methods: We used pooled data from two infant cohorts and estimated intakes of total wholegrain, dietary fibre and wholegrain subtypes from 7-day dietary records. Associations with HAZ, BMIZ and non-fasting plasma low-density (LDLC) and high-density-lipoprotein cholesterol, triacylglycerol, insulin and glucose were analysed in mixed models, adjusted for potential confounders.Results: Median (25th, 75th percentile) wholegrain intake was 7.5 (4.9, 10.5) and 6.5 (4.6, 9.0) g/MJ at 9 and 36 months. Neither wholegrain nor dietary fibre intake were associated with HAZ (P ≥ 0.09). At 36 months, wholegrain intake was inversely associated with LDLC (P = 0.05) and directly with glucose (P < 0.001). In secondary analyses, wholegrain rye was inversely associated with glucose at 9 months and insulin at 36 months (both P ≤ 0.03). Oat and wheat wholegrain were directly associated with glucose (both P ≤ 0.01) and wheat with BMIZ (P = 0.02) at 36 months.Conclusion: Danish infants and toddlers have high intakes of wholegrain and dietary fibre, with no indication of compromised growth. In line with studies in adults, wholegrain intake was inversely associated with LDLC. The observed direct association between wholegrain intake and plasma glucose and associations with wholegrain subtypes should be investigated further.

Background: A 2017 meta-analysis of data from 25 randomised controlled trials (RCTs) of vitamin D supplementation for the prevention of acute respiratory infections (ARIs) revealed a protective effect of this intervention. We aimed to examine the link between vitamin D supplementation and prevention of ARIs in an updated meta-analysis. Methods: For this systematic review and meta-analysis, we searched MEDLINE, Embase, the Cochrane Central Register of Controlled Trials, Web of Science, and the ClinicalTrials.gov registry for studies listed from database inception to May 1, 2020. Double-blind RCTs of vitamin D3, vitamin D2, or 25-hydroxyvitamin D (25[OH]D) supplementation for any duration, with a placebo or low-dose vitamin D control, were eligible if they had been approved by a research ethics committee, and if ARI incidence was collected prospectively and prespecified as an efficacy outcome. Studies reporting results of long-term follow-up of primary RCTs were excluded. Aggregated study-level data, stratified by baseline 25(OH)D concentration and age, were obtained from study authors. Using the proportion of participants in each trial who had one or more ARIs, we did a random-effects meta-analysis to obtain pooled odds ratios (ORs) and 95% CIs to estimate the effect of vitamin D supplementation on the risk of having one or more ARIs (primary outcome) compared with placebo. Subgroup analyses were done to estimate whether the effects of vitamin D supplementation on the risk of ARI varied according to baseline 25(OH)D concentration (<25 nmol/L vs 25·0–49·9 nmol/L vs 50·0–74·9 nmol/L vs >75·0 nmol/L), vitamin D dose (daily equivalent of <400 international units [IU] vs 400–1000 IU vs 1001–2000 IU vs >2000 IU), dosing frequency (daily vs weekly vs once per month to once every 3 months), trial duration (≤12 months vs >12 months), age at enrolment (&l

Purpose: Studies indicate that long-chain n-3 PUFA (n-3LCPUFA) affect sleep and physical activity (PA) in childhood. However, few studies used objective tools and none studies examined the effect of fish per se. We aimed to explore if fish consumption affected sleep and PA assessed by accelerometry in children, and if effects were modified by sex.Methods: In a randomized 12-week trial, 199 healthy 8-9-year-old children received ~ 300 g/week of oily fish or poultry. Sleep and PA were pre-specified explorative outcomes examined by accelerometers that the children wore on their hip for 7 days at baseline and endpoint, while parents registered sleep. Compliance was verified by erythrocyte n-3LCPUFA.Results: The children slept 9.4 ± 0.5 h/night but the sleep duration variability across the week was 6.0 (95%CI: 0.8, 11.1) min lower in the fish vs poultry group. Furthermore, children in the fish group exhibited increased spare time sedentary activity [9.4 (95%CI: 1.8, 16.9) min/day] at the expense of light PA [- 8.2 (95%CI: - 14.4, - 2.0) min/day]. These effects were supported by dose-dependency with n-3LCPUFA. Additionally, latency to sleep onset was reduced by 3.6 (95%CI: 1.0, 6.3) min on weekends and moderate-vigorous PA during school hours was 3.5 (95%CI: 0.1, 6.8) min longer in fish vs poultry. P values for sex interactions were all > 0.05 but the effects tended to be most pronounced on sleep in girls and PA in boys.Conclusion: Oily fish intake altered sleep and PA patterns among healthy schoolchildren, with some slight indications of sex differences. These findings warrant further investigation.Clinical trial registry: At clinicaltrials.gov (NCT02809508) and a published protocol in Trials [Damsgaard et al. in Trials, 2016].

Background: Vitamin D and dairy protein may stimulate bone mineralization and linear growth in children, but previous studies show inconsistent results and have not examined their combined effects.Objectives: To investigate combined and separate effects of vitamin D supplementation and high-protein (HP) compared with normal-protein (NP) yogurt intake on children's bone mineralization and linear growth.Methods: In a 2 × 2-factorial trial, 200 healthy, 6- to 8-year-old, Danish, children with light skin (55°N) were randomized to 20 µg/d vitamin D3 or placebo and to substitute 260 g/d dairy with HP (10 g protein/100 g) or NP (3.5 g protein/100 g) yogurt for 24 weeks during an extended winter. Outcomes were total body less head (TBLH) and lumbar spine bone mineral density (BMD), bone mineral content (BMC), and bone area (BA) by dual-energy X-ray absorptiometry, height, and biomarkers of bone turnover and growth. The primary outcome was TBLH BMD.Results: In total, 184 children (92%) completed the study. The baseline serum 25-hydroxyvitamin D was 80.8 ± 17.2 nmol/L, which increased by 7.2 ± 14.1 nmol/L and decreased by 32.3 ± 17.5 nmol/L with vitamin D and placebo, respectively. The baseline protein intake was 15.4 ± 2.4 energy percentage (E%), which increased to 18.3 ± 3.4 E% with HP. There were no vitamin D-yogurt interactions and no main effects of either intervention on TBLH BMD. However, vitamin D supplementation increased lumbar spine BMD and TBLH BMC compared to placebo, whereas HP groups showed lower increments in lumbar spine BMD, TBLH BMC and BA, and plasma osteocalcin compared to NP groups. Height, growth factors, and parathyroid hormone levels were unaffected.Conclusions: Although there were no effects on whole-body BMD, vitamin D increased bone mass and spinal BMD, whereas high compared with normal dairy protein intake had smaller incremental effects on these outcomes. This supports a

Objective: Milk protein may stimulate linear growth through insulin-like growth factor-1 (IGF-1). However, the effect of plant proteins on growth factors is largely unknown. This study assesses the effect of combinations of milk and rapeseed protein versus milk protein alone on growth factors in children.Design: An exploratory 3-armed randomized, double-blind, controlled trial was conducted in 129 healthy 7-8 year-old Danish children. Children received 35 g milk and rapeseed protein (ratio 54:46 or 30:70) or 35 g milk protein per day for 4 weeks. The primary outcome was difference in IGF-1 changes between intervention groups after 4 weeks. Secondary outcomes included changes in IGF-1 after 1 week and changes in insulin-like growth factor binding protein-3 (IGFBP-3), IGF-1/IGFBP-3, insulin, height, weight and body composition after 1 and 4 weeks. Results were analysed by multiple linear mixed-effect models.Results: There were no differences in changes of plasma IGF-1, insulin-like growth factor binding protein-3 (IGFBP-3), IGF-1/IGFBP-3 ratio or insulin between groups after 1 or 4 weeks based on 89 complete cases (P > 0.10). IGF-1 increased by 13.7 (95% CI 9.7;17.7) ng/mL and 18.0 (14.0;22.0) ng/mL from baseline to week 1 and 4, respectively, a 16% increase during the intervention. Similarly, insulin increased by 31% (14; 50) and 33% (16; 53) from baseline to week 1 and 4. Fat-free mass index (FFMI) increments were higher with milk alone than rapeseed blends (P < 0.05), coinciding with a trend towards a lower height increment. Body mass index increased within all groups (P < 0.05), mainly due to an increase in FFMI (P < 0.01).Conclusion: There were no differences in changes of growth factors between the combinations of milk and rapeseed protein and milk protein alone in healthy, well-nourished children with a habitual intake of milk. Within groups, growth factors increased con

We aimed to assess the test-retest reliability of five muscle strength and physical function tests in healthy children. Forty-one children (6–9 years) were tested three times 4–10 days apart. The test protocol included maximal isometric leg press, hand grip strength, squat jump, long jump, and a 30-sec sit-to-stand test (STST). When comparing test round 1 with 2 and 2 with 3, we found good-to-excellent retest reliability of leg press (intraclass correlation coefficient, ICC = 0.87 and ICC = 0.94), hand grip (ICC = 0.90 and ICC = 0.94), and long jump (ICC = 0.86 and ICC = 0.87). Initially, there was a moderate reliability of squat jump (ICC = 0.71), which was improved to ICC = 0.82 (round 2–3). Similarly, reliability of STST was improved from low (ICC = 0.63) to moderate reliability (ICC = 0.78). We conclude that leg press, hand grip, squat jump, and long jump tests are reliable measurements of children’s muscle strength and function, even without familiarization. Contrary, STST requires familiarization to ensure adequate reliability.

Body mass index (BMI) at child and adolescent ages is positively associated with adult coronary heart disease (CHD) whereas height at these ages may be inversely associated with CHD. However, potential effects of age, sex, and socioeconomic status on associations between BMI and CHD are less investigated. We conducted a systematic review and meta-analysis of BMI and height at ages 2-19 years in relation to adult CHD and examined effects of age, sex, socioeconomic status, and other factors. Twenty-two studies on BMI and five on height were included, comprising 5,538,319 individuals and 69,830 CHD events. Random effects meta-analyses were conducted. Child and adolescent BMI were positively associated with CHD (hazard ratio = 1.12; 95% confidence interval [CI] [1.01, 1.25] per standard deviation [SD]), and categorical analyses supported these findings. The associations did not significantly differ by age, sex, or by adjustment for socioeconomic status. Child and adolescent height were inversely associated with CHD (hazard ratio = 0.87; 95% CI [0.81, 0.93] per SD), and categorical analyses agreed. Insufficient studies on height precluded subgroup analyses. Heterogeneity was generally high in all analyses. We found that BMI in youth is positively associated with adult CHD regardless of sex or adjustment for socioeconomic status whereas height is inversely associated with later risk of CHD.

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions.

Long-chain n-3 PUFA (n-3 LCPUFA) are known to reduce blood pressure (BP), heart rate and vagal tone, but potential stress-mitigating effects of n-3 LCPUFA are not well investigated. We explored the effects of oily fish consumption on long-term stress and the stress response in schoolchildren. Healthy 8-9-year-old children were randomised to receive about 300 g/week of oily fish or poultry for 12 weeks (199 randomised, 197 completing). At baseline and endpoint, we measured erythrocyte n-3 LCPUFA, hair cortisol and the response to a 1-min cold pressor test (CPT) on saliva cortisol, BP and continuous electrocardiogram recordings. Post-intervention hair cortisol did not differ between the groups, but sex-specificity was indicated (Psex × group = 0·074, boys: -0·9 (95 % CI -2·9, 1·0) ng/g, girls: 0·7 (95 % CI -0·2, 1·6) ng/g). Children in the fish group tended to be less prone to terminate CPT prematurely (OR 0·20 (95 % CI 0·02, 1·04)). Mean heart beat interval during CPT was 18·2 (95 % CI 0·3, 36·6) ms longer and high frequency power increased (159 (95 % CI 29, 289) ms2) in the fish v. poultry group. The cardiac autonomic response in the 10 min following CPT was characterised by a sympathetic peak followed by a parasympathetic peak, which was most pronounced in the fish group. This exploratory study does not support a strong effect of oily fish consumption on stress but indicates that oily fish consumption may increase vagal cardiac tone during the physiological response to CPT. These results warrant further investigation.

Background: Comparable global data on health and nutrition of school-aged children and adolescents are scarce. We aimed to estimate age trajectories and time trends in mean height and mean body-mass index (BMI), which measures weight gain beyond what is expected from height gain, for school-aged children and adolescents.Methods: For this pooled analysis, we used a database of cardiometabolic risk factors collated by the Non-Communicable Disease Risk Factor Collaboration. We applied a Bayesian hierarchical model to estimate trends from 1985 to 2019 in mean height and mean BMI in 1-year age groups for ages 5-19 years. The model allowed for non-linear changes over time in mean height and mean BMI and for non-linear changes with age of children and adolescents, including periods of rapid growth during adolescence.Findings: We pooled data from 2181 population-based studies, with measurements of height and weight in 65 million participants in 200 countries and territories. In 2019, we estimated a difference of 20 cm or higher in mean height of 19-year-old adolescents between countries with the tallest populations (the Netherlands, Montenegro, Estonia, and Bosnia and Herzegovina for boys; and the Netherlands, Montenegro, Denmark, and Iceland for girls) and those with the shortest populations (Timor-Leste, Laos, Solomon Islands, and Papua New Guinea for boys; and Guatemala, Bangladesh, Nepal, and Timor-Leste for girls). In the same year, the difference between the highest mean BMI (in Pacific island countries, Kuwait, Bahrain, The Bahamas, Chile, the USA, and New Zealand for both boys and girls and in South Africa for girls) and lowest mean BMI (in India, Bangladesh, Timor-Leste, Ethiopia, and Chad for boys and girls; and in Japan and Romania for girls) was approximately 9-10 kg/m2. In some countries, children aged 5 years started with healthier height or BMI than the global median and, in some cases, as healthy as the best performing c

Background: Long-chain n-3 PUFAs (n-3 LCPUFAs) accrete in the brain during childhood and affect brain development. Randomized trials in children show inconsistent effects of n-3 LCPUFAs on cognitive and socioemotional function, and few have investigated effects of fish per se.Objectives: We aimed to investigate the effects of oily fish consumption on overall and domain-specific cognitive and socioemotional scores and explore sex differences.Methods: Healthy 8-9-y-old children (n = 199) were randomly allocated to receive ∼300 g/wk oily fish or poultry (control) for 12 ± 2 wk. At baseline and endpoint, we assessed attention, processing speed, executive functions, memory, emotions, and behavior with a large battery of tests and questionnaires and analyzed erythrocyte fatty acid composition.Results: One hundred and ninety-seven (99%) children completed the trial. Children in the fish group consumed 375 (25th-75th percentile: 325-426) g/wk oily fish resulting in 2.3 (95% CI: 1.9, 2.6) fatty acid percentage points higher erythrocyte n-3 LCPUFA than in the poultry group. The overall cognitive performance score tended to improve by 0.17 (95% CI: -0.01, 0.35) points in children who received fish compared with poultry, supported by n-3 LCPUFA dose dependency. This was driven mainly by fewer errors [-1.9 (95% CI: -3.4, -0.3)] in an attention task and improved cognitive flexibility measured as faster reaction time [-51 ms (95% CI: -94, -7 ms)] in a complex relative to a simple task ("mixing cost"). The fish intervention furthermore reduced parent-rated Strength and Difficulties Questionnaire total difficulties by -0.89 (95% CI: -1.60, -0.18) points mainly due to a -0.63 (95% CI: -1.11, -0.16) points reduction in internalizing problems that was reflected in tendency to a decrease in the overall socioemotional problems score of -0.13 (95% CI: -0.26, 0.01) points. The overall effects were similar in boys and girls.Concl

Purpose: Most children do not meet dietary guidelines for fish intake. Fish is the main source of EPA (20:5n-3), DHA (22:6n-3) and vitamin D, but may replace better iron sources such as meat. We investigated if intake of 300 g/week oily fish was achievable in children and how it affected their nutrient status. Additionally, we validated a fish food frequency questionnaire (FFQ) by correlations against EPA + DHA in red blood cells (RBC).Methods: In a randomised 12-week trial, 199 children (8-9 years) received oily fish or poultry (control) to be eaten five times/week. We measured dietary intake and analysed fasting RBC EPA + DHA, serum 25-hydroxyvitamin D (25(OH)D), blood haemoglobin and plasma ferritin.Results: 197 (99%) children completed the study. The median (25th-75th percentile) intake was 375 (325-426) and 400 (359-452) g/week oily fish and poultry, respectively. The fish group increased their intake of EPA + DHA by 749 (593-891) mg/day and vitamin D by 3.1 (1.6-3.8) µg/day. Endpoint RBC EPA + DHA was 2.3 (95% CI 1.9; 2.6) fatty acid %-point higher than the poultry group (P < 0.001). The fish group avoided the expected 25(OH)D winter decline (P < 0.001) and had 23%-point less vitamin D insufficiency (winter subgroup, n = 82). Haemoglobin and ferritin decreased slightly in both groups (P < 0.05), but the number of children with low values did not change (P > 0.14). FFQ estimates moderately reflected habitual intake (r = 0.28-0.35) and sufficiently captured intervention-introduced changes in intake (r > 0.65).Conclusion: Oily fish intake of 300 g/week was achievable and improved children's EPA + DHA and 25(OH)D status, without markedly compromising iron status. These results justify public health initiatives focusing on children's fish intake.

Purpose: To explore whether muscle strength, the insulin-like growth factor axis (IGF-axis), height, and body composition were associated with serum 25-hydroxyvitamin D [25(OH)D] and affected by winter vitamin D supplementation in healthy children, and furthermore to explore potential sex differences.Methods: We performed a double-blind, placebo-controlled, dose-response winter trial at 55ºN. A total of 117 children aged 4-8 years were randomly assigned to either placebo, 10, or 20 µg/day of vitamin D3 for 20 weeks. At baseline and endpoint, we measured muscle strength with handgrip dynamometer, fat mass index (FMI), fat free mass index (FFMI), height, plasma IGF-1, IGF-binding protein 3 (IGFBP-3), and serum 25(OH)D.Results: At baseline, serum 25(OH)D was positively associated with muscle strength, FFMI, and IGFBP-3 in girls only (all p < 0.01). At endpoint, baseline-adjusted muscle strength, FMI and FFMI did not differ between intervention groups. However, baseline-adjusted IGF-1 and IGFBP-3 were higher after 20 µg/day compared to placebo (p = 0.043 and p = 0.006, respectively) and IGFBP-3 was also higher after 20 µg/day compared to 10 µg/day (p = 0.011). Children tended to be taller after 20 µg/day compared to placebo (p = 0.064). No sex interactions were seen at endpoint.Conclusions: Avoiding the winter-related decline in serum 25(OH)D may influence IGF-1 and IGFBP-3 in children. Larger trials are required to confirm these effects, and the long-term implication for linear growth.

Long-chain n-3 polyunsaturated fatty acids (n-3 LCPUFA) have in some studies been associated with cognitive and socioemotional outcomes in children, but results are inconsistent possibly due to the use of different tests and potential gender-specific effects. The objective of this cross-sectional study was to explore overall patterns in neuropsychological scores as well as correlations between scores within specific domains, and to examine potential gender differences and consistency in associations with n-3 LCPUFA status. In 199 Danish 8-9 year-old children, we performed a large battery of tests and questionnaires on attention, processing speed, executive functions, memory, and socioemotional traits, and measured erythrocyte fatty acid composition. Principal component analyses (PCA) showed that most of the variation in both cognitive performance and socioemotional traits was explained by overall performance, followed by speed-accuracy trade off and externalizing vs. internalizing problems, respectively. Boys had higher speed, lower attention and higher externalizing problem scores than girls. Measures of performance within both processing speed and attention domains correlated moderately, whereas no correlations were found for measures of executive functions apart from some weak correlations for impulsivity. Parent-rated scores for both externalizing and internalizing problems correlated strongly, whereas correlations with child-rated scores were weak. Scores within specific domains did not consistently associate with n-3 LCPUFA, except for processing speed measures which all pointed to faster processing with increased n-3 LCPUFA status. Gender differences in the associations were observed for attention and impulsivity. Child- but not parent-rated internalizing and social problems tended to associate directly with n-3 LCPUFA, supported by increased internalizing problems measured by the PCA component. In conclusion, measures of speed and attention seem to repres

Body-mass index (BMI) has increased steadily in most countries in parallel with a rise in the proportion of the population who live in cities1,2. This has led to a widely reported view that urbanization is one of the most important drivers of the global rise in obesity3-6. Here we use 2,009 population-based studies, with measurements of height and weight in more than 112 million adults, to report national, regional and global trends in mean BMI segregated by place of residence (a rural or urban area) from 1985 to 2017. We show that, contrary to the dominant paradigm, more than 55% of the global rise in mean BMI from 1985 to 2017 - and more than 80% in some low- and middle-income regions - was due to increases in BMI in rural areas. This large contribution stems from the fact that, with the exception of women in sub-Saharan Africa, BMI is increasing at the same rate or faster in rural areas than in cities in low- and middle-income regions. These trends have in turn resulted in a closing-and in some countries reversal-of the gap in BMI between urban and rural areas in low- and middle-income countries, especially for women. In high-income and industrialized countries, we noted a persistently higher rural BMI, especially for women. There is an urgent need for an integrated approach to rural nutrition that enhances financial and physical access to healthy foods, to avoid replacing the rural undernutrition disadvantage in poor countries with a more general malnutrition disadvantage that entails excessive consumption of low-quality calories.

Objective: To explore determinants of serum 25-hydroxyvitamin D (s-25(OH)D) during autumn in young, Caucasian children not consuming vitamin D-fortified foods or supplements, and explore differences in sun behaviours between pre-school and school children.Design: In September-October, s-25(OH)D was measured by LC-MS/MS; physical activity, sun behaviours and vitamin D intake were assessed with questionnaires.Setting: Baseline data from the ODIN Junior trial at 55°N.Subjects: Children aged 4-8 years (n 130), of whom 96% gave blood samples.Results: Mean s-25(OH)D was 56·8 (SD 12·5) nmol/l and positively associated with fat-free mass index (P=0·014). Children being active 6-7 h/week had 5·6 (95% CI 1·1, 10·0) nmol/l higher s-25(OH)D than less active children (P=0·014). Children seeking shade sometimes or rarely/never had 7·0 (95% CI 1·2, 12·9; P=0·018) and 7·2 (95% CI 0·8, 13·6; P=0·028) nmol/l higher s-25(OH)D, respectively, than children always/often seeking shade. Pre-school children had more sun-safe behaviour than school children in terms of use of a hat, sunscreen and sunscreen sun protection factor (P<0·05). In school but not pre-school children, using a hat rarely/never was associated with 12·1 (95% CI 2·5, 21·7; P=0·014) nmol/l higher s-25(OH)D v. always/often (Pinteraction=0·019). Vitamin D intake was not associated with s-25(OH)D (P=0·241).Conclusions: Physical activity and sun behaviours are associated with s-25(OH)D in young children. Identifying factors influencing autumn s-25(OH)D is relevant to optimize levels before sun exposure diminishes. Strategies to reduce risk of inadequacy should consider risk of skin cancer and sunburn, and could include fortification and/or vitamin D supplementation.

Background: Low serum 25-hydroxyvitamin D [25(OH)D] has been associated with unfavorable cardiometabolic risk profiles in many observational studies in children, but very few randomized controlled trials have investigated this.Objective: We explored the effect of winter-time cholecalciferol (vitamin D3) supplementation on cardiometabolic risk markers in young, white, 4- to 8-y-old healthy Danish children (55°N) as part of the pan-European ODIN project.Methods: In the ODIN Junior double-blind, placebo-controlled, dose-response trial, 119 children (mean ± SD age: 6.7 ± 1.5 y; 36% male; 82% normal weight) were randomly allocated to 0, 10 or 20 µg/d of vitamin D3 for 20 wk (October-March). Cardiometabolic risk markers including BMI-for-age z score (BMIz), waist circumference, systolic and diastolic blood pressure, serum triglycerides and cholesterol (total, LDL, HDL, and total:HDL), plasma glucose and insulin, and whole-blood glycated hemoglobin were measured at baseline and endpoint as secondary outcomes together with serum 25(OH)D. Intervention effects were evaluated in linear regression models as between-group differences at endpoint adjusted for baseline value of the outcome, and additionally for age, sex, baseline serum 25(OH)D, BMIz, time since breakfast, and breakfast content.Results: Mean ± SD serum 25(OH)D was 56.7 ± 12.3 nmol/L at baseline and differed between groups at endpoint with concentrations of 31.1 ± 7.5, 61.8 ± 10.6, and 75.8 ± 11.5 nmol/L in the 0-, 10-, and 20 µg/d groups, respectively (P < 0.0001). Vitamin D3 supplementation had no effect on any of the cardiometabolic risk markers in analyses adjusted for baseline value of the outcome (all P ≥ 0.05), and additional covariate adjustment did not change the results notably.Conclusions: Preventing the winter decline in serum 25(OH)D with daily vitamin D3 supplementation of 10 or 20 µg had no cardiometabolic effects in healthy 4- to 8

Increased sedentariness has been linked to the growing prevalence of obesity in children, but some longitudinal studies suggest that sedentariness may be a consequence rather than a cause of increased adiposity. We used Mendelian randomization to examine the causal relations between body mass index (BMI) and objectively assessed sedentary time and physical activity in 3-8 year-old children from one Finnish and two Danish cohorts [NTOTAL=679]. A genetic risk score (GRS) comprised of 15 independent genetic variants associated with childhood BMI was used as the instrumental variable to test causal effects of BMI on sedentary time, total physical activity, and moderate-to-vigorous physical activity (MVPA). In fixed effects meta-analyses, the GRS was associated with 0.05 SD/allele increase in sedentary time (P=0.019), but there was no significant association with total physical activity (beta=0.011 SD/allele, P=0.58) or MVPA (beta=0.001 SD/allele, P=0.96), adjusting for age, sex, monitor wear-time and first three genome-wide principal components. In two-stage least squares regression analyses, each genetically instrumented one unit increase in BMI z-score increased sedentary time by 0.47 SD (P=0.072). Childhood BMI may have a causal influence on sedentary time but not on total physical activity or MVPA in young children. Our results provide important insights into the regulation of movement behaviour in childhood.International Journal of Obesity accepted article preview online, 26 September 2017. doi:10.1038/ijo.2017.235.

Background: Dietary and endogenously formed long-chain polyunsaturated fatty acids (LCPUFAs) are hypothesized to improve cognitive development, but results are inconclusive, with suggestions of sex specificity. One study suggested that single-nucleotide polymorphisms (SNPs) rs1535 and rs174448 in the fatty acid desaturase (FADS) gene cluster have opposite effects on erythrocyte LCPUFAs at 9 mo.Objective: To explore whether SNPs in FADS and elongase (ELOVL) genes were associated with school performance in a sex-specific manner, we performed a Mendelian randomization study using data from the Optimal well-being, development and health for Danish children through a healthy New Nordic Diet (OPUS) School Meal Study with 765 Danish schoolchildren 8-11 y old.Design: Associations between selected FADS1/2 SNPs (rs1535, rs174448, and rs174468) and ELOVL5 rs2397142, whole-blood fatty acid composition, and performance in the d2 Test of Attention and a reading test were analyzed in multiple regression models including all SNPs, SNP-sex interactions, and covariates related to testing conditions.Results:FADS, rs1535 minor allele carriage associated with lower whole-blood arachidonic acid (P ≤ 0.002), and minor alleles of rs174448 tended to associate with lower docosahexaenoic acid (DHA) (P = 0.052). We identified sex interactions in 50% of the SNP performance sets. Sex-dependent associations were observed for rs174448 and rs1535 on the d2 Test of Attention outcomes (P < 0.03) and for the associations between reading scores and rs174448 and rs2397142 (P < 0.01). All of the sex-specific analyses showed associations in opposite directions in girls and boys. The minor allele carriage of rs174448 was associated with lower d2 Test of Attention performance (P < 0.02) and reading scores (P < 0.001) in boys but with better reading scores in girls (P ≤ 0.002). The associations were consistently the opposite for rs1535 minor allele carriage (P < 0.05). Associations with rs2