Ute Alexy

Vitamin D status and parathyroid hormone in obese children before and after weight loss

OBJECTIVE The roles of vitamin D and parathyroid hormone (PTH) are discussed controversially in obesity, and studies of these hormones in obese children are limited. Therefore, we studied the relationships between PTH, 1,25-dihydroxy-vitamin D (1,25-OH Vit D), 25-hydroxy-vitamin D (25-OH Vit D), weight status, and insulin sensitivity before and after weight loss in obese children. METHODS Fasting serum PTH, 1,25-OH Vit D, 25-OH Vit D, inorganic phosphate, calcium, alkaline phosphatase (AP), insulin, glucose, and weight status (SDS-BMI and percentage body fat) were determined in 133 obese children (median age 12.1 years) and compared with 23 non-obese children. Furthermore, these parameters were analyzed in 67 obese children before and after participating in a 1-year obesity intervention program. RESULTS Obese children had significantly (P < 0.001) higher PTH and lower 25-OH Vit D concentrations compared with non-obese children, while calcium, phosphate, AP, and 1,25-OH Vit D did not differ significantly. Changes of PTH (r = 0.23, P = 0.031) and 25-OH Vit D (r = -0.27, P = 0.013) correlated significantly with changes of SDS-BMI, but not with changes of insulin sensitivity (homeostasis model assessment; HOMA-B%). Reduction of overweight in 35 children led to a significant (P < 0.01) decrease of PTH concentrations and an increase in 25-OH Vit D levels. CONCLUSIONS PTH levels were positively and 25-OH Vit D concentrations were negatively related to weight status. Since these alterations normalized after weight loss, these changes are consequences rather than causes of overweight. A relationship between PTH, vitamin D, and insulin sensitivity based on the HOMA index was not found in obese children. Further longitudinal clamp studies are necessary to study the relationship between vitamin D and insulin sensitivity.

Fifteen-year time trends in energy and macronutrient intake in German children and adolescents: results of the DONALD study

The DONALD study (Dortmund Nutritional and Anthropometric Longitudinally Designed study) gives the opportunity to evaluate long-term food and nutrient intake data on the basis of 3 d weighed dietary records of infants, children and adolescents since 1985. In this paper, we examine changes in energy and macronutrient intakes (protein, fat, saturated, mono- and polyunsaturated fatty acids, carbohydrates and added sugars) of 795 2-18-year-old subjects between 1985 and 2000 (4483 records). No significant changes in intakes of energy and of protein, polyunsaturated fatty acids and added sugars (as % energy intake, E %) were found. Fat intake decreased significantly in all age groups (between -0.20 and -0.26 E %/year), as well as intake of saturated fatty acids (between -0.11 and -0.14 E %/year) and monounsaturated fatty acids (between -0.07 and -0.014 E %/year). This decline was compensated for by a significant increase in carbohydrate intake (between +0.18 and +0.27 E %/year). The changes in macronutrient intake were mainly due to a decreased consumption of fats-oils (between -0.29 and -1.26 g/year) and meat-fish-eggs (between -0.21 and -2.92 g/year), whereas consumption of bread-cereals (between +0.12 and +2.42 g/year) and potatoes-pasta-rice (between +0.15 and +2.26 g/year) increased slightly. However, since recommended fat intake and fatty acid composition was not reached at the end of the study period by far, further efforts will be necessary to improve macronutrient composition and to stabilize favourable dietary habits.

Pattern of beverage consumption and long-term association with body-weight status in German adolescents--results from the DONALD study.

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.

Macronutrient Intake of 3- to 36-Month-Old German Infants and Children: Results of the DONALD Study

The intake of macronutrients (protein, fat, fatty acids, carbohydrates, added sugars, fiber) was assessed in 354 healthy German infants and children aged 3–36 months from 3-day weighed diet records. The intake of protein ranged between 7 and 14% of energy intake. Fat intake decreased from 3 months (breast-fed boys and girls, 48%; formula-fed boys/girls, 41/44%) to 12 months (boys/girls, 33/36%) due to the increasing consumption of commercial weaning foods, and then increased again up to 36 months (boys/girls, 40/43%). Intake of added sugars decreased during the first 12 months and then increased again, but only slightly exceeded the limit of 10%. Intake of dietary fiber was highest at the age of 1 year (boys/girls, 2.7/2.3 g/MJ). The macronutrient intake was in accordance with other German and European surveys, but deviated considerably from the respective recommendations.

Fruit juice consumption and the prevalence of obesity and short stature in german preschool children : Results of the DONALD study

BACKGROUND In recent years, a possible association between excessive consumption of fruit juice (> or =12 fl oz per day) and short stature and/or obesity has been discussed. The association among the consumption of fruit juice, anthropometric indices, and the overall diet was examined during a 3-year period in a sample of healthy preschool children participating in the Dortmund Nutritional and Anthropometrical Longitudinally Designed (DONALD) Study. METHODS Two hundred five children were examined annually at the ages of 3, 4, and 5 years. Dietary intake was calculated from 3-day weighed diet records. Height was measured using a stadiometer. Weight was measured using an electronic scale. RESULTS Five children consumed excessive fruit juice continually in all three records, 10 children in two records, and 23 children in one record. None of the five children with repeatedly excessive fruit juice consumption was obese or short. Growth velocity, body mass index, and height standard deviation score were not correlated with fruit juice consumption. Consumption of fruit juice was inversely correlated with the consumption of all other beverages and the total consumption of all other food. The intake of protein, fat, and carbohydrates of children consuming excessive fruit juice was closer to the international dietary preventive guidelines than the intake of children consuming low amounts of fruit juice. CONCLUSIONS In the study sample, even repeatedly excessive fruit juice consumption had no influence on anthropometric indices. The results do not justify a general warning or a general promotion regarding high fruit juice consumption in preschool childrens diets.

Consumption of dietary salt measured by urinary sodium excretion and its association with body weight status in healthy children and adolescents.

OBJECTIVE Highly processed foods such as convenience foods usually have a high salt content and therefore might indirectly act as adipogenic due to an increasing consumption of sugar-containing beverages (SCB). We examined the association between dietary salt and body weight status. DESIGN We used data on urinary Na excretion as an indicator of dietary salt and BMI standard deviation score (BMI-SDS) and percentage body fat (%BF) of children and adolescents participating in the DONALD (Dortmund Nutritional and Anthropometric Longitudinally Designed) Study. SETTING Dortmund, Germany. SUBJECTS Children and adolescents (n 364) who had at least two 24 h urine samples and two dietary records in the observational period between 2003 and 2009 were considered in our data analysis. RESULTS Repeated-measures regression models revealed that urinary Na was positively associated with BMI-SDS (+0·202 SDS/g Na excretion at baseline; P < 0·001) and %BF (+1·303 %BF/g Na excretion at baseline; P < 0·01) at baseline in boys and girls. These associations remained significant after adjustment for SCB consumption and total energy intake. Furthermore, there was a positive trend between baseline Na excretion and the individual change in %BF in the study period (+0·364 increase in %BF/g Na excretion at baseline), which was confirmed after inclusion of SCB consumption or total energy intake. There was no significant association between the change in Na excretion and the concurrent change of either BMI-SDS or %BF in any model. CONCLUSIONS Our results suggest that a high intake of processed salty foods could have a negative impact on body weight status in children and adolescents independently from their consumption of SCB.

Breakfast trends in children and adolescents: frequency and quality

OBJECTIVE Although breakfast is important for obesity prevention and dietary quality, breakfast skipping is a common behaviour. Knowledge of changes in breakfast habits may provide potential behaviour targets for intervention programmes. The present study describes the actual data on trends in breakfast habits and composition. DESIGN A total of 7800 3 d dietary records of 1081 participants aged 2-18 years collected between 1986 and 2007 in the DONALD (Dortmund Nutritional and Anthropometric Longitudinally Designed) Study were analysed using mixed linear models. RESULTS Breakfast was eaten at 78 % of all record days; regular breakfast (breakfast was eaten on all three recorded weekdays) was eaten in 75 % of records. During the study period, the number of records with regular breakfast decreased significantly in 6-12- and 13-18-year-olds (P = 0·0084 and 0·0350, respectively). Of all breakfast meals, 62 % were bread meals and 21 % were ready-to-eat cereal (RTEC) meals. RTEC meals nearly doubled from the youngest to the oldest age group (P < 0·0001). During the study period, the percentage of bread meals decreased, whereas the percentage of RTEC meals increased (P < 0·0001). A higher percentage of RTEC meals than the bread meals was in accordance with the food-based guidelines (36 % v. 20 %, P < 0·0001), i.e. a breakfast including grain, dairy and fruit/vegetables. CONCLUSIONS In the DONALD Study sample, a negative age and time trend in breakfast consumption was verified. Interventions regarding breakfast habits should be aimed at adolescents and should focus on fruit/vegetables.

Association between long-term consumption of soft drinks and variables of bone modeling and remodeling in a sample of healthy German children and adolescents

BACKGROUND Soft drinks are thought to displace milk in diets of children and adolescents and therefore might affect variables of bone modeling and remodeling. OBJECTIVE We assessed the association between long-term consumption of several types of soft drinks and bone variables in children and adolescents. DESIGN Long-term dietary data from 3-d weighed dietary records collected by 228 healthy children and adolescents enrolled in the DONALD Study in 4 y of study participation were used for data analysis. Variables of bone modeling and remodeling of the radius were assessed by using peripheral quantitative computed tomography. RESULTS After adjustment for age, sex, total energy intake, muscle area, BMI SD scores, and growth velocity, long-term consumption of all soft drinks and uncaffeinated soft drinks was negatively associated with bone mineral content (P < 0.05), cortical area (P < 0.05), and polar strength strain index (P < 0.05), all of which reflect a combination of bone modeling and remodeling. Long-term consumption of caffeinated soft drinks was negatively associated with polar strength strain index (P < 0.01) and periosteal circumference (P < 0.05), which reflect bone modeling. Milk intake was positively associated with polar strength strain index (P < 0.05). Consumption of all soft drinks was negatively associated with total protein and milk intake, but was not associated with potential renal acid load. CONCLUSIONS Long-term consumption of caffeinated and uncaffeinated soft drinks appears to have bone catabolic effects in boys and girls. This effect is mainly mediated by the negative association with total protein intake and is not primarily based on milk displacement.

Consumption of sugar-sweetened beverages and its association with nutrient intakes and diet quality in German children and adolescents.

In the present study the relationship of sugar-sweetened beverage (SSB) consumption with the intake of single nutrients and total diet quality in German children and adolescents was evaluated using a repeated-measures regression analysis model. We used dietary data from 7145 three-day weighed records of 1069 subjects aged 2-19 years participating in the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study. Intake of macronutrients as percentage of total energy intake (%En), intake of micronutrients as percentage of German reference values (intake quality score) and nutritional quality index (NQI) as an indicator of diet quality were chosen as separate dependent variables. SSB consumption was positively associated with %En from carbohydrates (boys v. girls: +4.00 v. +4.09 En%/MJ from SSB) and added sugars (boys v. girls: +7.36 v. +9.52 En%/MJ from SSB) and negatively with %En from protein (boys v. girls: - 1.25 v. - 1.31 En%/MJ from SSB) and fat (boys: - 2.82 v. - 2.73 En%/MJ from SSB). With respect to micronutrients, SSB consumption was negatively associated with folate and Ca intake, for which mean intake levels were inadequate in girls. Absolute diet quality was negatively associated with SSB consumption, whereas the effect was larger for girls (boys v. girls: - 1.41 v. - 2.63 points of NQI/MJ from SSB). Overall, results show a diluting effect of SSB consumption on micronutrient intake and diet quality. This effect might be relevant especially in girls as the association with diet quality was larger and mean NQI levels were lower in comparison with boys.

Dietary intake and food sources of minerals in 1 to 18 year old German children and adolescents

Data on the age- and sex-specific intakes of 10 minerals (sodium, potassium, calcium, phosphorus, magnesium, iron, zinc, iodine, copper, manganese) from 627 healthy German subjects aged 1 to 18 years were collected by 3-day weighed dietary records. Mineral intakes are reported as absolute amounts (per day), densities (per MJ) and proportions derived from 11 food groups. A comparison of these results with various national and international intake references revealed an overall satisfactory dietary mineral intake in German children and adolescents with the exception of an insufficient iodine intake. The diet of the 1 to 3 year old children had higher nutrient densities than the diet of the older age groups for most of the minerals. Milk and fruit were more important mineral sources for the 1 to 3 year old children, meat and confectionary were more important for the older age groups. Compared to the references, the mineral intake of females was often inferior than the mineral intake of males. By an increased consumption of plant foods and milk to the level of an overall preventive diet for children and adolescents, even the higher values among the current references for mineral intake could be reached with the exception of iodine.