Maike Wolters

Relation between salivary cortisol as stress biomarker and dietary pattern in children

PURPOSE Psychological stress has been suggested to result in hormonal effects (e.g. changes in cortisol pattern) that may change food selection in unhealthy ways. This study examines whether childrens dietary pattern is indeed related to salivary cortisol levels. METHODS In 323 children (5-10 years old) participating in the Belgian ChiBS study, salivary cortisol samples, a biomarker for stress, was sampled when waking up, 30 and 60 min after wake up and in the evening on two consecutive weekdays. Data on the childrens dietary pattern (frequency of sweet foods, fatty foods, snacks, fruit and vegetables) was collected with a food frequency questionnaire. Multilevel time modelling was used with adjustments for sex, age, body mass index, parental education and wake up time. RESULTS Higher overall cortisol levels and a large cortisol awakening response (CAR) were associated with more frequent consumption of sweet foods. A steeper diurnal cortisol decline was associated with a higher sweet, fatty and snack food consumption frequency. No associations with fruit and vegetables consumption were found. CONCLUSIONS High cortisol levels were linked to an unhealthier dietary pattern (more fatty food, snacks and especially sweet food). This supports the theory of cortisol-induced comfort food preference and strengthens the stress-diet relation.

Reference values of whole-blood fatty acids by age and sex from European children aged 3-8 years

Objectives:To establish reference values for fatty acids (FA) especially for n-3 and n-6 long-chain polyunsaturated FAs (LC PUFA) in whole-blood samples from apparently healthy 3–8-year-old European children. The whole-blood FA composition was analysed and the age- and sex-specific distribution of FA was determined.Design and subjects:Blood samples for FA analysis were taken from 2661 children of the IDEFICS (identification and prevention of dietary- and lifestyle-induced health effects in children and infants) study cohort. Children with obesity (n=454) and other diseases that are known to alter the FA composition (n=450) were excluded leaving 1653 participants in the reference population.Measurements:The FA composition of whole blood was analysed from blood drops by a rapid, validated gas chromatographic method.Results:Pearson correlation coefficients showed an age-dependent increase of C18:2n-6 and a decrease of C18:1n-9 in a subsample of normal weight boys and girls. Other significant correlations with age were weak and only seen either in boys or in girls, whereas most of the FA did not show any age dependence. For age-dependent n-3 and n-6 PUFA as well as for other FA that are correlated with age (16:0, C18:0 and C18:1n-9) percentiles analysed with the general additive model for location scale and shape are presented. A higher median in boys than in girls was observed for C20:3n-6, C20:4n-6 and C22:4n-6.Conclusions:Given the reported associations between FA status and health-related outcome, the provision of FA reference ranges may be useful for the interpretation of the FA status of children in epidemiological and clinical studies.

No breakfast at home: association with cardiovascular disease risk factors in childhood

Background/Objectives:Limited data exist regarding breakfast consumption and its association with cardiovascular disease (CVD) risk factors. This study investigates the relationship between breakfast routine and CVD risk factors in a multinational sample.Subjects/Methods:Cross-sectional data from eight European countries participating in the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) survey (2007–2008) were used. The sample included ;children 2 to <10 years of age (n=8863, 51.2% boys). The Mann–Whitney ;U-test and logistic regression were used to assess CVD risk factors ;among ;no breakfast (NBrH), occasional breakfast and daily breakfast at home (DBrH) consumption.Results:Male school-aged NBrH consumers, ;compared with ;DBrH consumers, ;were more likely to be overweight/obese (odds ratio (OR): 1.37, 95% confidence interval (CI)=1.05–1.79), to have higher risk for high-density lipoprotein (HDL) cholesterol levels lower than 40 mg/dl (OR: 1.69, 95% CI=1.24–2.30), triglycerides (TG) above 75 mg/dl (OR: 1.65, 95% CI=1.24–2.19) and sum of skinfolds greater than the 90th percentile (OR: 1.32, 95% CI=1.0–1.76). Female school-aged NBrH consumers ;compared with ;DBrH consumers ;had a higher risk for waist circumference greater than the 90th percentile (OR: 1.70, 95% CI=1.14–2.51), HDL cholesterol levels lower than 40 mg/dl (OR: 1.65, 95% CI=1.23–2.21), TG above 75 mg/dl (OR: 1.65, 95% CI=1.26–2.17) and total cholesterol/HDL cholesterol ratio >3.5 (OR: 1.39, 95% CI=1.09–1.77). Results remained significant after adjusting for daily physical activity in moderate-to-vigorous physical activity (MVPA) periods (in min/day). Male DBrH consumers, 6 to <10 years of age, had longer daily periods of MVPA compared with ;NBrH consumers ;(32.0±21.4 vs 27.5±18.8, P<0.05). For preschoolers, breakfast consumption was negatively associated with ;CVD risk factors but results of regression models were mostly insignificant.Conclusions:Daily breakfast consumption contributes to controlling school-aged children’s weight ;and lipid profile and promotes higher PA.

Desaturase Activity Is Associated With Weight Status and Metabolic Risk Markers in Young Children

CONTEXT Activity of delta-9, delta-6, and delta-5 desaturases (D9D, D6D, D5D) are associated with obesity, insulin resistance, and dyslipidemia. OBJECTIVE To investigate the association of estimated desaturase activities with weight status, insulin resistance, and dyslipidemia in children, cross-sectionally and longitudinally. DESIGN The IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants) cohort study was used, with examinations at baseline (T0) and after 2 years (T1). SETTING AND PARTICIPANTS Children aged 2 to less than 10 years from eight European countries were recruited in kindergartens/primary schools. Children with available data on fatty acids, outcome, and covariate information were included in the analyses. METHODS Whole blood fatty acids were analyzed in 2600 children at baseline. D9D (16:1n-7/16:0), D6D (20:3n-6/18:2n-6), and D5D (20:4n-6/20:3n-6) activities were estimated from product-precursor fatty acids ratios. Body mass index (BMI), Homeostatic Model Assessment index, and high-density lipoprotein cholesterol (HDL), and triglycerides (TG) served as outcomes for weight status, insulin resistance, and dyslipidemia, respectively. Linear and logistic regression and repeated measures models were used to assess the cross-sectional and longitudinal associations between desaturase activity and outcomes. RESULTS In the cross-sectional analysis, D9D and D6D were positively associated with BMI and TG z-scores and inversely with HDL z-scores. D5D was inversely associated with BMI and TG z-scores (ie, a D5D increase of 1 unit is associated with a BMI z-score decrease of 0.07 and a 28% lower odds ratio for TG ≥ 75th percentile). Longitudinally, similar associations were found for T0 desaturase activities with BMI and for T0 D6D with HDL at follow-up (T1). Baseline D6D and D5D were positively associated with the change of HDL z-score from T0 to T1, and D6D with the change of Homeostatic Model Assessment index z-score. CONCLUSION Desaturase activities are associated with metabolic risk markers already in young children and appear to predict the metabolic risk.

C-reactive protein reference percentiles among pre-adolescent children in Europe based on the IDEFICS study population

Objectives:C-reactive protein (CRP) is involved in a wide range of diseases. It is a powerful marker for inflammatory processes used for diagnostic and monitoring purposes. We aimed to establish reference values as data on the distribution of serum CRP levels in young European children are scarce.Subjects:Reference values of high-sensitivity CRP concentrations were calculated for 9855 children aged 2.0–10.9 years, stratified by age and sex. The children were recruited during the population-based European IDEFICS study (Identification and prevention of Dietary- and lifestyle-induced health Effects in Children and infantS) with 18 745 participants recruited from 2007 to 2010.Results:In 44.1 % of the children, CRP values were below or equal the detection limit of 0.2 mg/l. Median CRP concentrations showed a slight negative age trend in boys and girls, whereas serum CRP values were slightly higher in girls than in boys across all age groups.Conclusions:Our population-based reference values of CRP may guide paediatric practice as elevated values may require further investigation or treatment. Therefore, the presented reference values represent a basis for clinical evaluation and for future research on risk assessment of diseases associated with increased CRP levels among children.

Prospective associations between socioeconomically disadvantaged groups and metabolic syndrome risk in European children. Results from the IDEFICS study

OBJECTIVE Socioeconomic disadvantages during childhood are hypothesised to have negative implications for health. We aimed to investigate the association between socioeconomic disadvantages and childrens total metabolic syndrome (MetS) score at baseline and follow-up and the extent to which socioeconomic disadvantages over time and the accumulation of these socioeconomic disadvantages can affect childrens MetS risk. METHODS The two-year longitudinal IDEFICS study included 2401 European children (aged 2.0-9.9) with complete information of the 16,229 participating at baseline. Sociodemographic variables, psychosocial factors and lifestyle were proxy-reported via questionnaires. Socioeconomically disadvantaged groups included children from families with low income, low education, migrant origin, unemployed parents, parents who lacked a social network, and from non-traditional families. MetS risk score was calculated as the sum of z-scores of waist circumference, blood pressure, lipids and insulin resistance. Linear mixed-effects models were used to study the association between social disadvantages and MetS risk. Models were adjusted for sex, age, well-being and lifestyle (fruit and vegetables consumption, physical activity, screen time). RESULTS At both time points, children from low-income families (0.20 [0.03-0.37]); (β estimate and 99% confidence interval), children from non-traditional families (0.14 [0.02-0.26]), children whose parents were unemployed (0.31 [0.05-0.57]) and children who accumulated >3 disadvantages (0.21 [0.04-0.37]) showed a higher MetS score compared to non-socioeconomically disadvantaged groups. CONCLUSION Children from socioeconomically disadvantaged families are at high metabolic risk independently of diet, physical activity, sedentary behaviours and well-being. Interventions focusing on these socioeconomically disadvantaged groups should be developed to tackle health disparities.

The role of a FADS1 polymorphism in the association of fatty acid blood levels, BMI and blood pressure in young children—Analyses based on path models

Background The recent obesity epidemic in children also showed an increase in the prevalence of hypertension. As blood pressure (BP) is associated with (long-chain) polyunsaturated fatty acids (LC PUFA), genetic variation in desaturase enzymes being involved in the synthesis of LC PUFA may be associated with BP. This study aimed to investigate the direct effects (independent of mediating variables) and indirect effects (mediated through intermediate variables) of a common variant in the FADS1 gene, rs174546, known to affect delta-5 desaturase (D5D) activity on PUFA level, body mass index (BMI) and BP. Methods A subsample of the IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) baseline survey including 520 children aged 2 to <10 years from six European countries was included. The association between rs174546 (T<C) and BP z-score as well as the mediating effects of selected key PUFA levels (dihomo-gamma-linolenic acid, DGLA; arachidonic acid, ARA; eicosapentaenoic acid, EPA) or estimated D5D activity (D5D index) and BMI z-score were investigated through path model analyses, adjusting for sex, age, educational level of parents, family history of hypertension, lifestyle factors and blood levels of saturated and monounsaturated fatty acids, triglycerides and low density lipoprotein cholesterol. Whole blood fatty acids were measured by a validated gas chromatographic method and recorded as percentage of weight of all fatty acids detected. Results Minor allele carriers of the SNP rs174546 had significantly higher DGLA and lower ARA and EPA levels as well as a lower D5D index. Via ARA and BMI z-score, the polymorphism had an indirect lowering effect on systolic BP z-score for each additional T allele (standardized effect estimate -0.057, p = 0.007). For DGLA, EPA and D5D index, the indirect effects of rs174546 on systolic BP were also negative but did not reach significance. DGLA and EPA had an increasing indirect effect on systolic BP via BMI. Results for diastolic BP were in general similar but effect estimates were lower compared to systolic BP. Conclusion Genetic variation in FADS1 influences BP via ARA and BMI indicating a favorable effect of the minor allele in SNP rs174546. Thus, polymorphisms with an impact on the D5D activity may play a role for the BP level mediated through PUFA and BMI. Therefore, health effects of dietary n-6 and n-3 PUFA may vary depending on genetic FADS1 variants.

Blood fatty acid composition in relation to allergy in children aged 2-9 years: results from the European IDEFICS study.

Background/objectives:Blood polyunsaturated fatty acids (PUFA) are involved in allergy development, but the etiological role of n-6 and n-3 PUFA is still controversial. A European multicenter study of children (IDEFICS) provided the opportunity to explore the cross-sectional association between fatty acids (FA) and allergy.Subjects/methods:Blood FA levels were measured in 2600 children aged 2–9 years and were recorded as the percentage of weight of all FA detected. Logistic regression of allergy status on FA components was adjusted for age, sex, country, body mass index, family history of allergic disease, breast-feeding, and number of siblings. The results were given as odds ratios (OR) for current vs no allergy ever and an increase in FA by 1 s.d.Results:Overall, higher proportions of n-6 PUFA were associated with higher odds of allergy (OR=1.21 (1.05, 1.40)). Monounsaturated FA (MUFA) were associated with reduced risk for allergy (OR=0.75 (0.65, 0.87)), whereas saturated FA did not differ by allergy status. The strongest associations were observed in children <4 years old, with ORs of allergy given as 1.62 (1.15, 2.29) for n-3 PUFA and 0.63 (0.42, 0.95) for MUFA. With regard to individual FA, these associations were independently observed for docosapentaenoic acid (22:5 n-3) and oleic acid (18:1 n-9).Conclusions:Both PUFA subtypes were positively associated with allergy in an age-dependent manner, whereas MUFA was associated with less allergy. The observation of high proportions of n-3 PUFA in allergic children younger than 4 years might help to understand the nature of early onset of atopic disease.

Prospective associations between dietary patterns and high sensitivity C-reactive protein in European children: the IDEFICS study

PurposeThis prospective study explores high sensitivity C-reactive protein (hs-CRP) levels in relation to dietary patterns at two time points in European children.MethodsOut of the baseline sample of the IDEFICS study (n = 16,228), 4020 children, aged 2–9 years at baseline, with available hs-CRP levels and valid data from a food frequency questionnaire (FFQ) at baseline (T0) and 2 years later (T1) were included. K-means clustering algorithm based on the similarities between relative food consumption frequencies of the FFQ was applied. hs-CRP was dichotomized according to sex-specific cutoff points. Multilevel logistic regression was performed to assess the relationship between dietary patterns and hs-CRP adjusting for covariates.ResultsThree consistent dietary patterns were found at T0 and T1: ‘animal protein and refined carbohydrate’, ‘sweet and processed’ and ‘healthy’. Children allocated to the ‘protein’ and ‘sweet and processed’ clusters at both time points had significantly higher odds of being in the highest category of hs-CRP (OR 1.47; 95% CI 1.03–2.09 for ‘animal protein and refined carbohydrate’ and OR 1.44; 95% CI 1.08–1.92 for ‘sweet and processed’) compared to the ‘healthy’ cluster. The odds remained significantly higher for the ‘sweet and processed’ pattern (OR 1.39; 95% CI 1.05–1.84) when covariates were included.ConclusionsA dietary pattern characterized by frequent consumption of sugar and processed products and infrequent consumption of vegetables and fruits over time was independently related with inflammation in European children. Efforts to improve the quality of the diet in childhood may prevent future diseases related with chronic inflammation.

Towards microbiome-informed dietary recommendations for promoting metabolic and mental health: Opinion papers of the MyNewGut project

The gut microbiota coexists in partnership with the human host through adaptations to environmental and physiological changes that help maintain dynamic homeostatic healthy states. Break-down of this delicate balance under sustained exposure to stressors (e.g. unhealthy diets) can, however, contribute to the onset of disease. Diet is a key modifiable environmental factor that modulates the gut microbiota and its metabolic capacities that, in turn, could impact human physiology. On this basis, the diet and the gut microbiota could act as synergistic forces that provide resilience against disease or that speed the progress from health to disease states. Associations between unhealthy dietary patterns, non-communicable diseases and intestinal dysbiosis can be explained by this hypothesis. Translational studies showing that dietary-induced alterations in microbial communities recapitulate some of the pathological features of the original host further support this notion. In this introductory paper by the European project MyNewGut, we briefly summarize the investigations conducted to better understand the role of dietary patterns and food components in metabolic and mental health and the specificities of the microbiome-mediating mechanisms. We also discuss how advances in the understanding of the microbiomes role in dietary health effects can help to provide acceptable scientific grounds on which to base dietary advice for promoting healthy living.