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OBJECTIVE: Nutritional status provides helpful information of disease severity and treatment effectiveness. Body mass index standard deviation scores (BMI-SDS) provide an approximation of body composition and thus are frequently used to classify nutritional status of sick children and adolescents. However, the accuracy of estimating body composition in this population using BMI-SDS has not been assessed. Thus, this study aims to evaluate the accuracy of nutritional status classification in sick infants and adolescents using BMI-SDS, upon comparison to classification using percentage body fat (%BF) reference charts. DESIGN: BMI-SDS was calculated from anthropometric measurements and %BF was measured using dual-energy x-ray absorptiometry (DXA) for 393 sick children and adolescents (5 months-18 years). Subjects were classified by nutritional status (underweight, normal weight, overweight, and obese), using 2 methods: (1) BMI-SDS, based on age- and gender-specific percentiles, and (2) %BF reference charts (standard). Linear regression and a correlation analysis were conducted to compare agreement between both methods of nutritional status classification. %BF reference value comparisons were also made between 3 independent sources based on German, Canadian, and American study populations. RESULTS: Correlation between nutritional status classification by BMI-SDS and %BF agreed moderately (r (2) = 0.75, 0.76 in boys and girls, respectively). The misclassification of nutritional status in sick children and adolescents using BMI-SDS was 27% when using German %BF references. Similar rates observed when using Canadian and American %BF references (24% and 23%, respectively). CONCLUSIONS: Using BMI-SDS to determine nutritional status in a sick population is not considered an appropriate clinical tool for identifying individual underweight or overweight children or adolescents. However, BMI-SDS may be appropriate for longitudinal measurements or for screening purposes in large field studies. When accurate nutritional status classification of a sick patient is needed for clinical purposes, nutritional status will be assessed more accurately using methods that accurately measure %BF, such as DXA.

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Early onset of puberty may confer adverse health consequences. Thus, modifiable factors influencing the timing of puberty are of public health interest. Childhood overweight as a factor in the earlier onset of menarche has been supported by prospective evidence; nonetheless, its overall contribution may have been overemphasized, since secular trends toward a younger age at menarche have not been a universal finding during the recent obesity epidemic. Current observational studies suggest notable associations between dietary intakes and pubertal timing beyond contributions to an energy imbalance: children with the highest intakes of vegetable protein or animal protein experience pubertal onset up to 7 months later or 7 months earlier, respectively. Furthermore, girls with high isoflavone intakes may experience the onset of breast development and peak height velocity approximately 7-8 months later. These effect sizes are on the order of those observed for potentially neuroactive steroid hormones. Thus, dietary patterns characterized by higher intakes of vegetable protein and isoflavones and lower intakes of animal protein may contribute to a lower risk of breast cancer or a lower total mortality.

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OBJECTIVE: To investigate whether the development of body composition into adolescence differs among children with an early, average, or late pubertal growth spurt (age at take-off [ATO]). METHODS: Mixed-effect polynomial models were applied to serial anthropometric measurements spanning from 4 years before to 4 years after ATO in 215 DONALD participants. Sex-specific trajectories of fat mass index (FMI, FM/m(2) ), fat-free mass index (FFMI, FFM/m(2) ), and their z-scores were compared among those with an early, average, or late ATO. RESULTS: Compared with girls with a late ATO (reference group), those with an early or average ATO experienced a significant increase in FFMI z-scores [ß (standard error) for linear trends in early and average ATO group: +0.15 (0.05) FFMI z-scores/year (P = 0.001) and +0.11 (0.04) FFMI z-scores/year (P = 0.005), respectively, adjusted for early life factors]. Similar differences were observed in boys [adjusted ß (standard error): +0.20 (0.06) FFMI z-scores/year (P = 0.0004) and +0.07 (0.05) FFMI z-scores/year (P = 0.1), respectively]. Graphical illustration of the predicted trajectories revealed that differences in relative FFMI emerged from ATO onward. For FMI, comparison with late maturers showed a more pronounced quadratic trend (kg/m(2) /years(2) ) (P = 0.01) among early-maturing girls and a reduced linear trend in FMI z-scores/year (P = 0.04) among early-maturing boys. CONCLUSIONS: This longitudinal study suggests that children who experience an early pubertal growth spurt accrue progressively more fat-free mass during the first years of puberty than late-maturing peers of the same age. Higher levels of adiposity commonly observed in adults with early puberty onset are, thus, likely to develop subsequently in later adolescence.

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The extent to which the quality of dietary carbohydrates (CHO) changes throughout puberty is not known. We analysed trends in the quantity and quality of CHO intake among German adolescents by separately examining trends during puberty (pubertal trends) and trends in CHO intake from 1988 to 2007 (secular trends). Linear mixed-effects regression analyses were performed in 216 participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study who had provided weighed 3 d dietary records at the onset of the pubertal growth spurt (defined by age at take-off) and over the subsequent 4 years. Over the course of puberty, CHO quality changed little: added sugar intake from beverages increased in girls (0·25 (se 0·12) % energy (% E)/year, P = 0·04) and added sugar intake from sweets decreased in both sexes (boys: - 0·22 (se 0·11) % E/year, P = 0·049; girls: - 0·20 (se 0·10) % E/year, P = 0·04). For both sexes, significant upward secular trends were observed for CHO (% E), glycaemic load (g/MJ) and added sugar intakes from sources other than sweets and soft drinks (% E), while absolute fibre intake (g/d) decreased (P ≤ 0·04). Concomitant increases in total added sugar intake (% E) and decreases in fibre and whole-grain densities (g/MJ) (P = 0·001-0·02) were confined to boys only. The quality of dietary CHO consumed by healthy German adolescents shows notable secular declines, but does not change markedly during puberty. Public health initiatives should be tailored to improve the overall quality of CHO nutrition.

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Early puberty onset is associated with hormone-related cancers, but whether diet in childhood influences pubertal timing is controversial. We examined the association of protein intake in early and mid-childhood with the ages at take-off of the pubertal growth spurt (ATO), peak height velocity (APHV), and menarche in girls and voice break in boys using data from the longitudinal Dortmund Nutritional and Anthropometric Longitudinally Designed Study. Among participants who provided 3-d weighed dietary records at 12 mo, 18-24 mo, 3-4 y, and 5-6 y, 112 had sufficient anthropometric measurements between 6 and 13 y to allow estimation of ATO. Life-course plots were used to identify critical periods of total, animal, and vegetable protein intake (percentage of total energy intake) for pubertal timing. At these ages, the association between tertiles of protein intake (T1-T3) and the outcomes was investigated using multiple linear regression analysis. A higher total and animal protein intake at 5-6 y was related to an earlier ATO. In the highest tertile of animal protein intake at 5-6 y, ATO occurred 0.6 y earlier than in the lowest [(mean, 95% CI) T1: 9.6, 9.4-9.9 vs. T2: 9.4, 9.1-9.7 vs. T3: 9.0, 8.7-9.3 y; P-trend = 0.003, adjusted for sex, total energy, breast-feeding, birth year, and paternal university degree]. Similar findings were seen for APHV (P-trend = 0.001) and the timing of menarche/voice break (P-trend = 0.02). Conversely, a higher vegetable protein intake at 3-4 and 5-6 y was related to later ATO, APHV, and menarche/voice break (P-trend = 0.02-0.04). These results suggest that animal and vegetable protein intake in mid-childhood might be differentially related to pubertal timing.

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We examined whether the diet quality of healthy children prior to the pubertal growth spurt was associated with age and body composition at puberty onset. Multivariate regression analyses were performed using data from 222 Dortmund Nutritional and Anthropometric Longitudinally Designed Study participants (mean age +/- SD at baseline: 7.4 +/- 1.3 y) with 3-d weighed dietary records and anthropometric data at baseline, i.e. the visits 2 and 3 y before the onset of pubertal growth spurt [defined as age at take-off (ATO)]. Diet quality at baseline was determined using the nutrient density-based Nutritional Quality Index (NQI) and the food group and nutrient-based Revised Children's Diet Quality Index (RC-DQI). Based on their distribution, 3 NQI or RC-DQI categories were created to indicate lower, moderate, and higher diet quality. Parameters describing body composition at ATO were age- and gender-specific Z-scores of BMI, fat mass/height(2), and fat-free mass/height(2). Children with lower diet quality indicated by lower NQI scores entered puberty approximately 0.4 y earlier than children with higher NQI scores {ATO in lower and higher NQI categories were [mean (95% CI)] 9.2 y (9.0-9.4), and 9.6 y (9.4-9.9), adjusted for sex, maternal overweight, baseline energy intake, and baseline BMI Z-score} (P-value = 0.02). A similar association of the RC-DQI with ATO was largely explained by baseline energy intakes. Our data suggest that diet quality was not independently associated with body composition at ATO. Children with lower diet quality according to a nutrient density-based index appear to enter puberty at an earlier age, independently of prepubertal body composition.

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BACKGROUND: Early age at puberty onset may predispose an individual to many currently prevalent diseases, including cancer and adiposity. OBJECTIVE: The objective was to investigate whether early life exposures influence the timing of puberty, as defined by both early and late markers, in healthy German girls and boys. DESIGN: Term participants (n = 215; 49.8% female) of the DONALD (DOrtmund Nutritional and Anthropometric Longitudinally Designed) Study, with sufficient repeated anthropometric measurements between 6 and 13 y to allow estimation of age at take-off of the pubertal growth spurt (ATO) and information on a variety of early life exposures, including birth weight, breastfeeding status, velocity of weight gain, and parental characteristics, were studied. Age at peak height velocity (APHV) and menarche were also considered. RESULTS: Children who weighed between 2500 and <3000 g at birth were approximately 7 mo younger at ATO than were the other children (beta +/- SE: -0.56 +/- 0.20 y; P = 0.006). Children who had gained weight rapidly between birth and 24 mo (increase in weight SD score >0.67) experienced ATO 4 mo earlier than those who had gained weight normally (-0.34 +/- 0.15 y; P = 0.02). Rapid weight gain was also associated with an earlier APHV (P = 0.0006) and, in girls, with an earlier menarche (P = 0.002). Adjustment for body mass index SD score or body fat percentage 1, 2, or 3 y before ATO did not account for these effects. CONCLUSION: In both boys and girls, intrauterine and early postnatal growth factors appear to influence both early and later markers of puberty onset independently of prepubertal body composition.

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The authors prospectively examined whether change in dietary glycemic index (GI), glycemic load (GL), fiber intake, or whole-grain intake during puberty is associated with concurrent change in percentage of body fat (%BF) or body mass index (BMI; weight (kg)/height)(2). Linear mixed-effects regression analyses were performed in 215 participants from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study (Dortmund, Germany) who possessed weighed 3-day dietary records and anthropometric data at puberty onset (defined by age at takeoff) and over the subsequent 4 years (1988-2007). Neither changes in dietary GI, GL, fiber intake, nor whole-grain intake were associated with concurrent changes in %BF throughout puberty (change in %BF: -0.03 (standard error (SE), 0.11) per standard deviation (SD) increase in GI (P = 0.8); -0.01 (SE, 0.11) per SD increase in GL (P = 0.9); 0.02 (SE, 0.14) per SD increase in fiber intake (P = 0.9); and 0.09 (SE, 0.13) per SD increase in whole-grain intake (P = 0.5)). Similarly, no concurrent associations were observed between these dietary factors and BMI SD scores. Associations of dietary GI with %BF and BMI SD score differed between overweight and normal-weight adolescents (for concurrent association, P for interaction was 0.03 for %BF and 0.08 for BMI SD score). Dietary GI, GL, and fiber and whole-grain intakes in healthy, free-living adolescents do not appear to be relevant to the development of %BF or BMI during puberty.

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BACKGROUND: It is controversial whether prepubertal body composition is implicated in the timing of puberty onset. OBJECTIVE: The objective was to investigate whether body composition in the 2 y preceding the start of the pubertal growth spurt -- a marker of puberty onset -- is associated with the attainment of early and late pubertal markers in healthy German boys and girls. DESIGN: Multivariate-adjusted regression analyses were performed in 215 participants of the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study for whom body mass index (BMI) and its components fat mass/height(2) (FM/m(2)) and fat-free mass/height(2) (FFM/m(2)) 1 and 2 y before the onset of the pubertal growth spurt (age at takeoff; ATO) and information on early life exposures were available. In addition, age at peak height velocity (APHV) and menarche were examined. RESULTS: Higher BMIs and FM/m(2) z scores 1 and 2 y before ATO showed modest associations with chronological age at ATO among girls only (girls: P for = trend 0.05-0.1, adjusted for early life factors; boys: P = 0.2-0.6). FFM/m(2) z scores were not related to age at ATO (P for trend = 0.5-0.8). Conversely, prepubertal BMI and FM/m(2) more clearly predicted APHV and puberty duration (APHV minus ATO) in both sexes and age at menarche in girls (girls: adjusted P for trend <0.0001-0.03; boys: P = 0.01-0.046). CONCLUSION: This longitudinal study suggests that prepubertal body composition in healthy boys and girls may not be critical for the initiation of the pubertal growth spurt but instead affects the progression of pubertal development, which results in earlier attainment of later pubertal stages.

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BACKGROUND: Observational studies in adults suggest that a diet with a high glycemic index (GI) or glycemic load (GL), a high intake of sugary foods, or a low fiber intake may increase the risk of overweight. OBJECTIVES: We aimed to examine prospectively whether dietary GI, GL, added sugar intake, or fiber intake between age 2 and 7 y are associated with the development of body composition. If so, we aimed to ascertain whether these associations are modified by meal frequency. DESIGN: Linear mixed-effect regression analyses were performed in 380 participants of the DOrtmund Nutrition and Anthropometric Longitudinally Designed (DONALD) Study for whom 4-6 weighed 3-d dietary records and anthropometric data were obtained between ages 2 and 7 y. RESULTS: Changes in dietary GI, GL, or added sugar intake between ages 2 and 7 y were not associated with concurrent changes in percentage body fat (%BF, as estimated from skinfold thicknesses) or body mass index SD scores. An increase in fiber intake was related to a concurrent decrease in %BF between ages 2 and 7 y only in children who consumed <6 meals/d as toddlers (beta +/- SE from fully adjusted model: -0.26 +/- 0.09%BF per 1-SD increase in fiber intake, P = 0.005), whereas children with a higher meal frequency had no concurrent change (0.07 +/- 0.07%BF per 1-SD increase in fiber intake, P = 0.3). CONCLUSIONS: Dietary GI, GL, or added sugar intake between ages 2 and 7 y does not appear to influence the development of body composition. Potential benefits associated with increasing fiber intake throughout childhood may be limited to toddlers with a lower meal frequency.

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BACKGROUND: It is unclear which exposures may cause or modify the adverse effect of rapid weight gain on fat mass development in term children whose birth weight is appropriate-for-gestational age (AGA). OBJECTIVE: To determine which intrauterine or postnatal exposures increase the risk of or modify the effect of rapid weight gain on body fat percentage (BF%) and body mass index (BMI) trajectories between 2 and 6 y of age. DESIGN: Term AGA singletons (n = 370) from the German Multicenter Allergy Study (MAS-90), a longitudinal birth cohort study, with repeated anthropometric measurements until 6 y, and data on breastfeeding status, exposure to smoking during pregnancy, and maternal anthropometric and socioeconomic characteristics were included in this analysis. RESULTS: A shorter gestation [multivariate-adjusted odds ratio (OR): 5.12; 95% CI: 2.22, 11.82; P = 0.0001], being firstborn (OR: 2.01; 95% CI: 1.10, 3.69; P = 0.02), and having been bottle-fed (OR: 3.02; 95% CI: 1.68, 5.43; P = 0.0002) all significantly increased a child's risk of gaining weight rapidly, whereas a larger BMI at birth was protective (OR: 0.54; 95% CI: 0.38, 0.77; P = 0.0006). Multilevel model analyses showed that rapid growers exposed to tobacco in utero subsequently gained more BF% between 2 and 6 y than did rapid growers who had not been exposed (beta +/- SE: 0.78 +/- 0.28%/y; P = 0.005). Similarly, change in BF% was greater in rapid growers with an overweight mother than in those with a normal-weight mother (1.01 +/- 0.30%/y; P = 0.0007). CONCLUSIONS: The occurrence of rapid weight gain between birth and 2 y and the magnitude of its effect on BF% development in AGA children is influenced by both intrauterine and postnatal exposures.

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OBJECTIVE: To investigate the effect of breastfeeding in healthy boys and girls on their trajectories of percent body fat (%BF) and BMI standard deviation scores (BMI-SDS) throughout childhood. METHODS AND PROCEDURES: Analyses of the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study included data from 219 male and 215 female term participants, born between 1984 and 1999, with repeated anthropometric measurements between 0.5 and 7 years and prospective data on duration of breastfeeding. RESULTS: Among boys with an overweight mother (OW-M), analyses adjusted for potential confounders revealed that not or shortly breastfed (< or =17 weeks) boys did not experience the age-dependent decrease in %BF seen in all children with normal weight mothers (NW-Ms). In contrast, boys fully breastfed for >17 weeks were protected against the adverse effect of maternal overweight (effect of long breastfeeding vs. no/short breastfeeding among boys with OW-Ms: 0.46%/year; s.e. 0.18; P = 0.01). There was also a suggestion of an interaction between maternal overweight and breastfeeding for the BMI-SDS trajectory (0.08 SDS/year; s.e. 0.04; P = 0.07). Among boys with NW-Ms mothers and the corresponding subgroups of girls, breastfeeding had little effect on the development of %BF or BMI-SDS throughout childhood. DISCUSSION: Our study suggests that breastfeeding could offset a potential programming effect for childhood adiposity among boys with OW-Ms, to whom advice to breast-feed should thus be specifically targeted.

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In the present study the relationship between the consumption of different beverage groups and body-weight status in 5 years of study participation in German adolescents was investigated. We used anthropometric and dietary data from 3 d weighed records of 244 subjects between 9 and 18 years of age participating in the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study. Only subjects with at least four out of six possible weighed dietary records were considered. A repeated-measures regression model (PROC MIXED) was used to analyse the effect of beverage consumption on body-weight status. BMI standard deviation scores (BMI-SDS) and body fat percentage (%BF) were chosen as the dependent variables. In boys, energetic beverage consumption was not associated with BMI-SDS or %BF, neither cross-sectionally nor prospectively. In girls, baseline consumption of energetic beverages did not predict baseline BMI-SDS, baseline %BF, or change in either variable over the study period. However, an increase in energetic beverage consumption over the study period was associated with an increase in BMI-SDS (+0.070 SDS/MJ increase in energetic beverage consumption; P = 0.01). Separate consideration of regular soft drinks and fruit juices revealed that, in girls, BMI-SDS increased with increased fruit juice consumption (+0.096 SDS/MJ increase in fruit juice consumption; P = 0.01), and to a lesser extent with regular soft drink consumption (+0.055 SDS/MJ increase in regular soft drink consumption; P = 0.08). In conclusion, these results suggest that an increase in energetic beverage consumption may result in weight gain, at least in adolescent girls.

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BACKGROUND: It is not clear whether the adverse effects of rapid weight gain in infancy are modified by nutrition during the first 2 y of life in term children whose birth weight was appropriate for gestational age (AGA). OBJECTIVE: We examined the interaction between rapid weight gain and nutrition in infancy and early childhood and their effect on body fat percentage (BF%) trajectories between 2 and 5 y of age. DESIGN: The study population comprised 249 (51.4% female) term AGA participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study, for whom repeated anthropometric measurements until 5 y of age and information on breastfeeding status and on diet at 12 and 18-24 mo of age were available. RESULTS: Multilevel model analyses showed that, among rapid growers, those who had been fully breastfed for > or =4 mo had a lower BF% at 2 y of age than did those who had not been fully breastfed for > or =4 mo (beta +/- SE: -1.53 +/- 0.59%; P = 0.009). This difference persisted until 5 y. Furthermore, those rapid growers who had a consistently high fat intake at both 12 and 18-24 mo did not show the expected physiologic decrease in BF% between 2 and 5 y seen in those rapid growers with an inconsistent or consistently low fat intake at these time points (0.73 +/- 0.26%/y; P = 0.006). CONCLUSIONS: Among rapid growers, full breastfeeding for > or =4 mo is protective against a high BF% at 2 y of age, whereas a consistently high fat intake in the second year of life "inhibits" the physiologic decrease in BF% between 2 and 5 y.

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BACKGROUND: It is not clear whether and how rapid growth in infancy, a risk factor for later obesity, differentially affects growth and body-composition development throughout childhood in term children with an appropriate-for-gestational age (AGA) birth weight. OBJECTIVE: The aim was to examine the effect of rapid growth in infancy on body mass index SD score (BMI SDS) and body fat percentage (%BF) trajectories until age 7 y. DESIGN: This analysis included 206 (50.5% female) AGA term participants of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study. Repeated anthropometric measurements were obtained between 0.5 and 7 y of age. RESULTS: Fifty-nine of the 206 children (28.6%) displayed rapid growth (an increase in SDS for weight of >0.67 between birth and age 2 y). From 6 mo of age, their growth trajectories diverged from normal growers, and by age 7 y they had a higher BMI, more fat mass, and a higher risk of overweight (odds ratio: 6.2; 95% CI: 2.4, 16.5; P = 0.0002). Multilevel model analyses showed that the differences in BMI were achieved within the first 2 y of life [beta (+/-SE) SDS: 1.22 +/- 0.13], after which they persisted at this level until the age of 7 y, whereas differences in %BF, which were also already discernible by age 2 y (1.52 +/- 0.34%), became progressively larger over the next 5 y (adjusted difference: 0.23 +/- 0.11%/y; P = 0.03). CONCLUSIONS: Rapid growth in infancy and early childhood results in an increased BMI and %BF throughout childhood and an increased risk of overweight at age 7 y among AGA children. Rapid growth in AGA children has a more pronounced effect on %BF than on BMI.

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