The effects of hypothetical behavioral interventions on the 13-year incidence of overweight/obesity in children and adolescents.

BACKGROUND: In view of the high burden of childhood overweight/obesity (OW/OB), it is important to identify targets for interventions that may have the greatest effects on preventing OW/OB in early life. Using methods of causal inference, we studied the effects of sustained behavioral interventions on the long-term risk of developing OW/OB based on a large European cohort. METHODS: Our sample comprised 10 877 children aged 2 to < 10 years at baseline who participated in the well-phenotyped IDEFICS/I.Family cohort. Children were followed from 2007/08 to 2020/21. Applying the parametric g-formula, the 13-year risk of developing OW/OB was estimated under various sustained hypothetical interventions on physical activity, screen time, dietary intake and sleep duration. Interventions imposing adherence to recommendations (e.g. maximum 2 h/day screen time) as well as interventions 'shifting' the behavior by a specified amount (e.g. decreasing screen time by 30 min/day) were compared to 'no intervention' (i.e. maintaining the usual or so-called natural behavior). Separately, the effectiveness of these interventions in vulnerable groups was assessed. RESULTS: The 13-year risk of developing OW/OB was 30.7% under no intervention and 25.4% when multiple interventions were imposed jointly. Meeting screen time and moderate-to-vigorous physical activity (MVPA) recommendations were found to be most effective, reducing the incidence of OW/OB by -2.2 [-4.4;-0.7] and -2.1 [-3.7;-0.8] percentage points (risk difference [95% confidence interval]), respectively. Meeting sleep recommendations (-0.6 [-1.1;-0.3]) had a similar effect as increasing sleep duration by 30 min/day (-0.6 [-0.9;-0.3]). The most effective intervention in children of parents with low/medium educational level was being member in a sports club; for children of mothers with OW/OB, meeting screen time recommendations and membership in a sports club had the largest effects. CONCLUSIONS: While the effects of single behavioral interventions sustained over 13 years were rather small, a joint intervention on multiple behaviors resulted in a relative reduction of the 13-year OW/OB risk by between 10 to 26%. Individually, meeting MVPA and screen time recommendations were most effective. Nevertheless, even under the joint intervention the absolute OW/OB risk remained at a high level of 25.4% suggesting that further strategies to better prevent OW/OB are required.

Associations between food portion sizes, insulin resistance, VO2 max and metabolic syndrome in European adolescents: The HELENA study.

BACKGROUND AND AIMS: This study aims to examine the associations of food portion size (PS) with markers of insulin resistance (IR) and clustered of metabolic risk score in European adolescents. METHODS: A total of 495 adolescents (53.5% females) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study were included. The association between PS from food groups and homeostasis model assessment of insulin resistance (HOMA-IR) index, VO2 max, and metabolic risk score was assessed by multilinear regression analysis adjusting for several confounders. Analysis of covariance (ANCOVA) was used to determine the mean differences of food PS from food groups by HOMA-IR cutoff categories by using maternal education as a covariable. RESULTS: Larger PS from vegetables in both gender and milk, yoghurt, and milk beverages in males were associated with higher VO2 max, while larger PS from margarines and vegetable oils were associated with lower VO2 max (p < 0.05). Males who consumed larger PS from fish and fish products; meat substitutes, nuts, and pulses; cakes, pies, and biscuits; and sugar, honey, jams, and chocolate have a higher metabolic risk score (p < 0.05). Males with lower HOMA-IR cutoff values consumed larger PS from vegetables, milk, yoghurt, and milk beverages (p < 0.05). Females with lower HOMA-IR cutoff values consumed larger PS from breakfast cereals, while those with higher HOMA-IR cutoff values consumed larger PS from butter and animal fats (p = 0.018). CONCLUSION: The results show that larger PS from dairy products, cereals, and high energy dense foods are a significant determinant of IR and VO2 max, and larger PS from food with higher content of sugar were associated with higher metabolic risk score.

Cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness in European children and adolescents.

In this large perspective cohort among European children and adolescents, we observed that daytime napping was positively associated with bone stiffness, while short or long sleep duration combined with poor sleep quality was associated with less bone stiffness. Our findings are important for obtaining optimal bone stiffness in childhood. INTRODUCTION: To examine the cross-sectional and longitudinal associations between sleep duration, sleep quality, and bone stiffness index (SI) in European children and adolescents. METHODS: Four thousand eight hundred seventy-one children aged 2-11 years from the IDEFICS study and 861 children aged 6-15 years from the subsequent I.Family study were included. Sleep duration (i.e., nocturnal sleep and daytime napping) and sleep quality (i.e., irregularly bedtime routine, have difficulty falling asleep and trouble getting up in the morning) were reported by self-administrated questionnaires. Nocturnal sleep duration was converted into age-specific z-scores, and total sleep duration was classified into short, adequate, and long based on the National Sleep Recommendation. Calcaneal SI of both feet were measured using quantitative ultrasound. Linear mixed-effects models with country as a random effect were used, with adjustments for sex, age, pubertal status, family socioeconomic status, physical activity, screen time, body mass index, and daylight duration. RESULTS: Nocturnal sleep duration z-scores were positively associated with SI percentiles among participants with adequate sleep duration at baseline. Moreover, the positive association between daytime napping and SI percentiles was more pronounced in participants with adequate sleep duration at baseline, while at 4-year follow-up was more pronounced in participants with short sleep duration. In addition, extreme sleep duration at baseline predicted lower SI percentiles after 4 years in participants with poor sleep quality. CONCLUSION: The positive associations between nocturnal sleep, daytime napping and SI depended on total sleep duration. Long-term detrimental effect of extreme sleep duration on SI only existed in individuals with poor sleep quality.

Dietary sources of free sugars in the diet of European children: the IDEFICS Study.

OBJECTIVE: To report dietary free sugars consumption and their different types and food sources in European children. METHODS: The present study is based on the IDEFICS study, a European multicenter cohort study in children (2-9 years old) from eight countries, comprising 8308 children (51.4% males). Dietary intake of the previous 24 h was assessed using a computer-assisted 24-h dietary recalls (24-HDR) and the different types of sugars were assessed using the German food composition database. RESULTS: Mean total energy intake was 1720 (SD 477) kcal/d for boys and 1631 (SD 451) kcal/d for girls. Total sugars intake was 98 (SD 52) g/day for boys and 93 (SD 49) g/day for girls. Free sugars intake was 81 (SD 49) g/day for boys and 77 (SD 47) g/day for girls. Girls had significantly lower intakes of energy, total and free sugars compared with than boys but did not differ in terms of percent of energy from total (23%) or free sugars (18%). There were large variations between countries in average % energy from free sugars (ranging from 13% in Italy to 27% in Germany). Less than 20% of children were within the recommended intake of 10% of energy from free sugars. The food groups that contributed substantially to free sugars intakes were "Fruit juices", "Soft drinks", "Dairy" and "Sweets and candies". CONCLUSIONS: The contribution of free sugars to total energy intake in European children is higher than recommendations. The main food contributors to free sugars intake are sweetened beverages ("Fruit juices" and "Soft drinks"). It is especially important to reduce children's intake of free sugars, focusing in target population on certain foods and food groups.

Dietary calcium intake and adiposity in children and adolescents: Cross-sectional and longitudinal results from IDEFICS/I.Family cohort.

BACKGROUND AND AIMS: Studies in children and adolescents suggest that higher dairy consumption may exert a protective effect on adiposity. However, only few studies examined the association between dietary calcium intake and body mass measures with conflicting results. We evaluated the association between total dietary calcium, calcium from dairy and non-dairy sources and anthropometric indices in a large European cohort of children and adolescents. METHODS AND RESULTS: As many as 6,696 children belonging to the IDEFICS study were eligible for the cross-sectional analysis (Boys = 51%; age 6.0 ± 1.8 years; mean ± SD). Of these, 2,744 were re-examined six years later (Boys = 49.6%; age = 11.7 ± 1.8 years) in the framework of the I.Family study. The exposures were the baseline energy-adjusted total, dairy and non-dairy calcium intakes measured by a validated 24-h dietary recall. Multivariable linear regression was used to determine the association between calcium intake and z-scores of anthropometric indices (body mass index, BMI; waist circumference, WC; sum of skinfolds, SS; fat mass index, FMI) at baseline, and their variation over the 6 years follow-up. The association of dietary calcium with the incidence of overweight/obesity was also assessed. At baseline, an inverse association between total calcium intake and all the adiposity indices was consistently observed in boys, while only SS and FMI were significant in girls. The prevalence of overweight/obesity decreased significantly (P < 0.0001) across tertiles of calcium intake, in both sexes. Over the follow-up, boys with higher baseline calcium intake value showed significantly lower increase in BMI, WC and FMI z-scores, while in girls only a lower increase in WC z-score was observed. Only in boys, the risk to become overweight/obese decreased significantly across tertiles of calcium intake. Similar results were observed by analyzing only dietary calcium from dairy, while no association was observed between non-dairy calcium and adiposity indices. CONCLUSIONS: We showed in a large cohort of European children and adolescents that dietary calcium intake may play a role in the modulation of body fat in developmental age. The association between dietary calcium and adiposity indices was driven by dairy calcium, while no effect was observed for non-dairy calcium intake. The existence of a sex-related difference in the association deserves further investigations.

A within-sibling pair analysis of lifestyle behaviours and BMI z-score in the multi-centre I.Family study.

BACKGROUND AND AIMS: By investigating differences in lifestyle behaviours and BMI in sibling pairs, family-level confounding is minimized and causal inference is improved, compared to cross-sectional studies of unrelated children. Thus, we aimed to investigate within-sibling pair differences in different lifestyle behaviours and differences in BMI z-scores in children and adolescents. METHODS AND RESULTS: We examined three groups of sibling pairs 1) all same-sex sibling pairs with maximum 4 years age difference (n = 1209 pairs from 1072 families in 8 countries, mean age 10.7 years, standard deviation 2.4 years), 2) sibling pairs discordant for overweight (n = 262) and 3) twin pairs (n = 85). Usual dietary intake was estimated by 24-h recalls and time spent in light (LPA) and moderate-to-vigorous physical activity (MVPA) was measured by accelerometers. Screen time, sleep and dieting for weight loss were assessed by questionnaires. Within all 3 groups of sibling pairs, more time in MVPA was associated with lower BMI z-score. Higher energy intake was associated with higher BMI z-score within twin pairs and within all sibling pairs who were not currently dieting for weight loss. Regarding LPA, screen time or sleep duration, no or inconsistent associations were observed for the three groups of sibling pairs. CONCLUSIONS: MVPA and energy intake were associated with BMI differences within sibling and twin pairs growing up in the same home, thus independent of family-level confounding factors. Future studies should explore whether genetic variants regulating appetite or energy expenditure behaviours account for weight differences in sibling pairs.

Dietary sources of sugars in adolescents' diet: the HELENA study.

OBJECTIVE: To report dietary sugars consumption and their different types and food sources, in European adolescents. METHODS: Food consumption data of selected groups were obtained from 1630 adolescents (45.6% males, 12.5-17.5 years) from the HELENA study using two nonconsecutive 24-h recalls. Energy intake, total sugars and free sugars were assessed using the HELENA-DIAT software. Multiple regression analyses were performed adjusting for relevant confounders. RESULTS: Total sugars intake (137.5 g/day) represented 23.6% and free sugars (110.1 g/day), 19% of energy intake. Girls had significantly lower intakes of energy, carbohydrates, total sugars and free sugars. 94% of adolescents had a consumption of free sugars above 10% of total energy intake. The main food contributor to free sugars was 'carbonated, soft and isotonic drinks,' followed by 'non-chocolate confectionary' and 'sugar, honey, jam and syrup.' Older boys and girls had significantly higher intakes of free sugars from 'cakes, pies and biscuits.' Free sugars intake was negatively associated with low socioeconomic status for 'non-chocolate confectionary' and 'sugar, honey and jam' groups; with low maternal educational level for carbonated and 'soft drinks,' 'sugar, honey and jam,' 'cakes and pies' and 'breakfast cereals' groups; and with high paternal educational level for 'carbonated and soft drinks' and 'chocolates' group. CONCLUSIONS: The majority (94%) of studied adolescents consumed free sugars above 10% of daily energy intake. Our data indicate a broad variety in foods providing free sugars. Continued efforts are required at different levels to reduce the intake of free sugars, especially in families with a low educational level.

Inflammation in metabolically healthy and metabolically abnormal adolescents: The HELENA study.

BACKGROUND AND AIMS: Inflammation may influence the cardio-metabolic profile which relates with the risk of chronic diseases. This study aimed to assess the inflammatory status by metabolic health (MH)/body mass index (BMI) category and to assess how inflammatory markers can predict the cardio-metabolic profile in European adolescents, considering BMI. METHODS AND RESULTS: A total of 659 adolescents (295 boys) from a cross-sectional European study were included. Adolescents were classified by metabolic health based on age- and sex-specific cut-off points for glucose, blood pressure, triglycerides, high density cholesterol and BMI. C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin (IL-6), complement factors (C3, C4) and cell adhesion molecules were assessed. RESULTS: Metabolically abnormal (MA) adolescents had higher values of C3 (p < 0.001) and C4 (p = 0.032) compared to those metabolically healthy (MHy). C3 concentrations significantly increased with the deterioration of the metabolic health and BMI (p < 0.001). Adolescents with higher values of CRP had higher probability of being in the overweight/obese-MH group than those allocated in other categories. Finally, high C3 and C4 concentrations increased the probability of having an unfavorable metabolic/BMI status. CONCLUSIONS: Metabolic/BMI status and inflammatory biomarkers are associated, being the CRP, C3 and C4 the most related inflammatory markers with this condition. C3 and C4 were associated with the cardio-metabolic health consistently.

Relationship between sleep duration and childhood obesity: Systematic review including the potential underlying mechanisms.

AIM: The prevalence of obesity is continually increasing worldwide. Determining risk factors for obesity may facilitate effective preventive programs. The present review focuses on sleep duration as a potential risk factor for childhood obesity. The aim is to summarize the evidence on the association of sleep duration and obesity and to discuss the underlying potential physiological and/or pathophysiological mechanisms. DATA SYNTHESIS: The Ovid MEDLINE, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) databases were searched for papers using text words with appropriate truncation and relevant indexing terms. All studies objectively measuring sleep duration and investigating the association between sleep duration and obesity or factors (lifestyle and hormonal) possibly associated with obesity were included, without making restrictions based on study design or language. Data from eligible studies were extracted in tabular form and summarized narratively. After removing duplicates, 3540 articles were obtained. Finally, 33 studies (including 3 randomized controlled trials and 30 observational studies) were included in the review. CONCLUSION: Sleep duration seems to influence weight gain in children, however, the underlying explanatory mechanisms are still uncertain. In our review only the link between short sleep duration and the development of insulin resistance, sedentarism and unhealthy dietary patterns could be verified, while the role of other mediators, such as physical activity, screen time, change in ghrelin and leptin levels, remained uncertain. There are numerous evidence gaps. To answer the remaining questions, there is a need for studies meeting high methodological standards and including a large number of children.

Analysis of the association of leptin and adiponectin concentrations with metabolic syndrome in children: Results from the IDEFICS study.

BACKGROUND AND AIMS: Adipokines may play a role in the pathogenesis of the metabolic syndrome (MetS) in children. We aimed to evaluate the association of leptin, adiponectin, and its ratio (L/A ratio) with the metabolic syndrome (MetS) in a subsample of the IDEFICS (Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS) cohort. METHODS AND RESULTS: Leptin, adiponectin and MetS parameters were measured in a subsample of 1253 children (3-9.9 years) participating to the IDEFICS study, grouped as: Non-OW (underweight/normal weight) and OW/Ob (overweight/obese). MetS was defined using the sex- and age-specific cut-offs based on the distribution of MetS components in the IDEFICS cohort. The prevalence of the MetS among OW/Ob was 24.8% and 27.1% in boys and girls respectively, whereas ≤2% among Non-OW. OW/Ob had significantly higher leptin and L/A ratio as compared to Non-OW. Significantly higher leptin was found in OW/Ob with MetS as compared with OW/Ob without MetS. Significantly lower adiponectin was observed only in OW/Ob girls as compared to Non-OW. A 1SD increase in leptin and L/A ratio z-scores or a 1SD decrease in adiponectin z-score were significantly associated with higher risk of MetS. After adjustment for BMI or body fat mass (BFM) the association remained significant only for leptin. CONCLUSION: We showed that in European children, higher leptin concentration is associated with MetS, even after adjusting for BMI or BFM, confirming an early role of leptin in MetS, while the association of adiponectin with MetS seems be mediated by body fat in this age range.

Ideal cardiovascular health and inflammation in European adolescents: The HELENA study.

BACKGROUND AND AIMS: Inflammation plays a key role in atherosclerosis and this process seems to appear in childhood. The ideal cardiovascular health index (ICHI) has been inversely related to atherosclerotic plaque in adults. However, evidence regarding inflammation and ICHI in adolescents is scarce. The aim is to assess the association between ICHI and inflammation in European adolescents. METHODS AND RESULTS: As many as 543 adolescents (251 boys and 292 girls) from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study, a cross-sectional multi-center study including 9 European countries, were measured. C-reactive protein (CRP), complement factors C3 and C4, leptin and white blood cell counts were used to compute an inflammatory score. Multilevel linear models and multilevel logistic regression were used to assess the association between ICHI and inflammation controlling by covariates. Higher ICHI was associated with a lower inflammatory score, as well as with several individual components, both in boys and girls (p < 0.01). In addition, adolescents with at least 4 ideal components of the ICHI had significantly lower inflammatory score and lower levels of the study biomarkers, except CRP. Finally, the multilevel logistic regression showed that for every unit increase in the ICHI, the probability of having an inflammatory profile decreased by 28.1% in girls. CONCLUSION: Results from this study suggest that a better ICHI is associated with a lower inflammatory profile already in adolescence. Improving these health behaviors, and health factors included in the ICHI, could play an important role in CVD prevention.

Fruit and vegetables consumption is associated with higher vitamin intake and blood vitamin status among European adolescents.

BACKGROUND/OBJECTIVES: Current research in adults indicates that fruit and vegetable (FAV) consumption increases serum levels of vitamins C, E and folate of ß-carotene and reduces homocysteine concentrations. The aim of the present study was to examine the association of FAV consumption on vitamin intakes and their impact on blood vitamin concentrations in European adolescents. SUBJECT/METHODS: This multi-center cross-sectional study included 702 (53.7% females) adolescents, aged 12.50-17.49 years, from 10 European cities. Two independent self-administered 24 h dietary recalls were used to estimate the adolescent's diet. The total energy, vitamins and FAV consumption were calculated. Adolescents were categorized into three groups: (i) very low FAV intake (<200 g/day); (ii) low FAV consumption (200-399 g/day) and (iii) adequate FAV consumption (⩾400 g/day). Adolescent's fasted blood samples were taken for their analysis on vitamin concentrations. RESULTS: The main results showed that those adolescents meeting the FAV recommendation, classified as FAV adequate consumers, presented higher intake of energy and some vitamins as B6, total folic acid, C, E and ß-carotene compared with FAV very low consumers (P<0.05). Regarding their blood status, male adolescents who had a very low FAV consumption presented lower plasma folate, RBC folate blood concentrations compared with adequate FAV consumers (P<0.05). Female adequate FAV consumers had higher concentrations of pyridoxal phosphate (PLP), plasma folate, RBC folate, vitamin C, ß-carotene and α-tocopherol compared with very low and low consumers (P<0.05). CONCLUSIONS: Having a FAV dairy intake above 400 g/day is associated with higher vitamin intake and blood vitamin concentrations, especially for antioxidant and B-vitamins concentrations.

Folate and vitamin B12 concentrations are associated with plasma DHA and EPA fatty acids in European adolescents: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study.

This study aimed to examine the association between vitamin B6, folate and vitamin B12 biomarkers and plasma fatty acids in European adolescents. A subsample from the Healthy Lifestyle in Europe by Nutrition in Adolescence study with valid data on B-vitamins and fatty acid blood parameters, and all the other covariates used in the analyses such as BMI, Diet Quality Index, education of the mother and physical activity assessed by a questionnaire, was selected resulting in 674 cases (43 % males). B-vitamin biomarkers were measured by chromatography and immunoassay and fatty acids by enzymatic analyses. Linear mixed models elucidated the association between B-vitamins and fatty acid blood parameters (changes in fatty acid profiles according to change in 10 units of vitamin B biomarkers). DHA, EPA) and n-3 fatty acids showed positive associations with B-vitamin biomarkers, mainly with those corresponding to folate and vitamin B12. Contrarily, negative associations were found with n-6:n-3 ratio, trans-fatty acids and oleic:stearic ratio. With total homocysteine (tHcy), all the associations found with these parameters were opposite (for instance, an increase of 10 nmol/l in red blood cell folate or holotranscobalamin in females produces an increase of 15·85 µmol/l of EPA (P value <0·01), whereas an increase of 10 nmol/l of tHcy in males produces a decrease of 2·06 µmol/l of DHA (P value <0·05). Positive associations between B-vitamins and specific fatty acids might suggest underlying mechanisms between B-vitamins and CVD and it is worth the attention of public health policies.

Actual and perceived weight status and its association with slimming and energy-balance related behaviours in 10- to 12-year-old European children: the ENERGY-project.

BACKGROUND: Both parents' and children's perception of children's weight status may be important predictors of slimming and energy-balance related behaviours, independent of children's actual weight status. OBJECTIVES: We examined the cross-sectional association of children's self-reported slimming and energy-balance related behaviours with children's (i) actual, (ii) self-perceived and (iii) parent-perceived weight status. METHODS: Data of 10- to 12-year-old European children and their parents were used. Multilevel logistic and linear regression analyses were performed, adjusting for age, gender, parental weight controlling behaviours, education, marital status and ethnicity. RESULTS: Independent of their actual weight status, a higher proportion of children reported slimming when they or their parents perceived them as too fat. Children's self-perceived weight status was more strongly associated with slimming than their parents' perception or their actual weight status. Moreover, children who perceive themselves as overweight reported less physical activity and more screen time. Children whose parents perceive them as overweight reported less physical activity. CONCLUSIONS: Children's own perception of their weight status appears to be more important for their self-reported slimming than their actual or their parent's perceptions of their weight status. Additionally, children's self-perceived weight status seems important in engaging more physical activity and reduces screen time.

Potential selection effects when estimating associations between the infancy peak or adiposity rebound and later body mass index in children.

INTRODUCTION: This study aims to evaluate a potential selection effect caused by exclusion of children with non-identifiable infancy peak (IP) and adiposity rebound (AR) when estimating associations between age and body mass index (BMI) at IP and AR and later weight status. SUBJECTS AND METHODS: In 4744 children with at least 4 repeated measurements of height and weight in the age interval from 0 to 8 years (37 998 measurements) participating in the IDEFICS (Identification and Prevention of Dietary- and Lifestyle-Induced Health Effects in Children and Infants)/I.Family cohort study, fractional polynomial multilevel models were used to derive individual BMI trajectories. Based on these trajectories, age and BMI at IP and AR, BMI values and growth velocities at selected ages as well as the area under the BMI curve were estimated. The BMI growth measures were standardized and related to later BMI z-scores (mean age at outcome assessment: 9.2 years). RESULTS: Age and BMI at IP and AR were not identifiable in 5.4% and 7.8% of the children, respectively. These groups of children showed a significantly higher BMI growth during infancy and childhood. In the remaining sample, BMI at IP correlated almost perfectly (r⩾0.99) with BMI at ages 0.5, 1 and 1.5 years, whereas BMI at AR correlated perfectly with BMI at ages 4-6 years (r⩾0.98). In the total study group, BMI values in infancy and childhood were positively associated with later BMI z-scores where associations increased with age. Associations between BMI velocities and later BMI z-scores were largest at ages 5 and 6 years. Results differed for children with non-identifiable IP and AR, demonstrating a selection effect. CONCLUSIONS: IP and AR may not be estimable in children with higher-than-average BMI growth. Excluding these children from analyses may result in a selection bias that distorts effect estimates. BMI values at ages 1 and 5 years might be more appropriate to use as predictors for later weight status instead.

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.

Dietary fat intake modifies the influence of the FTO rs9939609 polymorphism on adiposity in adolescents: The HELENA cross-sectional study.

BACKGROUND AND AIMS: The fat mass and obesity associated gene (FTO) has been associated with obesity and dietary intake. The aims were: (i) To assess whether energy and macronutrient intakes were different across the FTOrs9939609 genotypes in adolescents, and (ii) to explore whether dietary fat intake modified the association of the rs9939609 polymorphism with adiposity. METHODS AND RESULTS: The FTOrs9939609 polymorphism was genotyped in 652 adolescents (53% females, 14.8 ± 1.2 years, TT = 246, TA = 296, AA = 110). Energy and macronutrient intake were assessed by two non-consecutive 24 h-recalls. Weight, height, waist circumference and skinfold thicknesses were measured and body fat percent was calculated. Energy and macronutrient intake were similar across the FTOrs9939609 genotypes (P > 0.2). There were significant interactions between the FTO polymorphism and fat intake on adiposity estimates (P < 0.05). In adolescents whose fat intake was below 30% (N = 203), the A allele of rs9939609 was not associated with adiposity indices. In contrast, in adolescents whose fat intake was between 30% and 35% of energy (N = 190), the rs9939609 polymorphism was associated with a 1.9% higher body fat per risk allele (95%CI: 0.39, 3.33; P < 0.05), and in those whose fat intake was higher than 35% (N = 259), it was associated with a 2.8% higher body fat per risk allele (95%CI: 1.27, 4.43; P < 0.001). CONCLUSIONS: These findings support the concept that the deleterious effect of the FTOrs9939609 polymorphism on adiposity is exacerbated in adolescents consuming high fat diets. In contrast, the consumption of low fat diets (<30% of energy) may attenuate the genetic predisposition to obesity in risk allele carriers.