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1.
Ambio ; 53(7): 970-983, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38696060

RESUMEN

The EU Nature Restoration Law (NRL) is critical for the restoration of degraded ecosystems and active afforestation of degraded peatlands has been suggested as a restoration measure under the NRL. Here, we discuss the current state of scientific evidence on the climate mitigation effects of peatlands under forestry. Afforestation of drained peatlands without restoring their hydrology does not fully restore ecosystem functions. Evidence on long-term climate benefits is lacking and it is unclear whether CO2 sequestration of forest on drained peatland can offset the carbon loss from the peat over the long-term. While afforestation may offer short-term gains in certain cases, it compromises the sustainability of peatland carbon storage. Thus, active afforestation of drained peatlands is not a viable option for climate mitigation under the EU Nature Restoration Law and might even impede future rewetting/restoration efforts. Instead, restoring hydrological conditions through rewetting is crucial for effective peatland restoration.


Asunto(s)
Conservación de los Recursos Naturales , Unión Europea , Agricultura Forestal , Suelo , Conservación de los Recursos Naturales/legislación & jurisprudencia , Conservación de los Recursos Naturales/métodos , Agricultura Forestal/legislación & jurisprudencia , Agricultura Forestal/métodos , Suelo/química , Bosques , Secuestro de Carbono , Restauración y Remediación Ambiental/métodos , Cambio Climático , Ecosistema , Humedales
3.
Sci Total Environ ; 877: 162943, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36934933

RESUMEN

Growing Sphagnum on rewetted bogs (=Sphagnum paludiculture) is an alternative to drainage-based land use because it retains its value as productive land while mitigating greenhouse gas (GHG) emissions. However, studies on GHG exchange covering the full production system and cycle are missing. Here, we combined data of the establishment phase with newly recorded data of a 7-year old Sphagnum paludiculture site in Germany including partial Sphagnum harvest. GHGs were measured with closed chambers at all elements of the system (production fields, ditches, causeways). Over the full production cycle, the production fields were GHG sinks with -3.2 ± 4.2 t ha-1 a-1 (in CO2-eq), while ditches represented sources emitting 13.8 ± 11.5 t ha-1 a-1. New measurements on the causeway indicated that it was a stronger GHG source with 29.3 ± 9.8 t ha-1 a-1 than previously assumed from literature values. Corrected for the area share of its elements and including the partial Sphagnum harvest (in dry mass) of ~13.8 ± 0.6 t ha-1 (=average 7-year CO2 emissions of 3.3 ± 0.1 t ha-1 a-1), the site was a GHG source of 10.7 ± 4.6 t ha-1 a-1, thus reducing emissions by ~20 t ha-1 a-1 compared to the German emission factor for grassland on drained organic soils. Per ton harvested dry biomass, the paludiculture site emitted 9.9 ± 4.6 t of CO2-eq. The causeways were the major contributor to the warming, calling for reducing causeway area in Sphagnum paludicultures. Future 'best-practice' could realistically comprise areal shares of 80 % production fields, 5 % ditches, 15 % causeways and a full Sphagnum harvest with the uppermost 5 cm remaining on site for recovery. In this scenario the site would emit CO2-eq emissions of 4.3 ± 1.9 t ha-1 a-1 or 0.9 ± 2.1 t per ton harvested dry mass.


Asunto(s)
Gases de Efecto Invernadero , Sphagnopsida , Gases de Efecto Invernadero/análisis , Humedales , Dióxido de Carbono/análisis , Pradera , Metano/análisis , Suelo , Alemania , Óxido Nitroso/análisis
4.
Environ Sci Technol ; 57(12): 5089-5101, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36926875

RESUMEN

Rewetted peatlands are reestablished hot spots for CH4 emissions, which are subject to increased drought events in the course of climate change. However, the dynamics of soil methane-cycling microbiomes in rewetted peatlands during summer drought are still poorly characterized. Using a quantitative metatranscriptomic approach, we investigated the changes in the transcript abundances of methanogen and methanotroph rRNA, as well as mcrA and pmoA mRNA before, during, and after the 2018 summer drought in a coastal and a percolation fen in northern Germany. Drought changed the community structure of methane-cycling microbiomes and decreased the CH4 fluxes as well as the rRNA and mRNA transcript abundances of methanogens and methanotrophs, but they showed no recovery or increase after the drought ended. The rRNA transcript abundance of methanogens was not correlated with CH4 fluxes in both fens. In the percolation fen, however, the mcrA transcript abundance showed a positive and significant correlation with CH4 fluxes. Importantly, when integrating pmoA abundance, a stronger correlation was observed between CH4 fluxes and mcrA/pmoA, suggesting that relationships between methanogens and methanotrophs are the key determinant of CH4 turnover. Our study provides a comprehensive understanding of the methane-cycling microbiome feedbacks to drought events in rewetted peatlands.


Asunto(s)
Euryarchaeota , Microbiota , Metano , Suelo , Sequías , Microbiología del Suelo
5.
FEMS Microbiol Ecol ; 97(9)2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34427631

RESUMEN

In the last decades, rewetting of drained peatlands is on the rise worldwide, to restore their significant carbon sink function. Despite the increasing understanding of peat microbiomes, little is known about the seasonal dynamics and network interactions of the microbial communities in these ecosystems, especially in rewetted fens (groundwater-fed peatlands). Here, we investigated the seasonal dynamics in both prokaryotic and eukaryotic microbiomes in three common fen types in Northern Germany. The eukaryotic microbiomes, including fungi, protists and microbial metazoa, showed significant changes in their community structures across the seasons in contrast to largely unaffected prokaryotic microbiomes. Furthermore, our results proved that the dynamics in eukaryotic microbiomes in the rewetted sites differed between fen types, specifically in terms of saprotrophs, arbuscular mycorrhiza and grazers of bacteria. The co-occurrence networks also exhibited strong seasonal dynamics that differed between rewetted and drained sites, and the correlations involving protists and prokaryotes were the major contributors to these dynamics. Our study provides the insight that microbial eukaryotes mainly define the seasonal dynamics of microbiomes in rewetted fen peatlands. Accordingly, future research should unravel the importance of eukaryotes for biogeochemical processes, especially the under-characterized protists and metazoa, in these poorly understood ecosystems.


Asunto(s)
Eucariontes , Microbiota , Secuestro de Carbono , Estaciones del Año , Suelo
6.
Plant Environ Interact ; 2(1): 16-27, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37283846

RESUMEN

Tree stems can be a source of the greenhouse gas methane (CH4). However, assessments of the global importance of stem CH4 emissions are complicated by a lack of research and high variability between individual ecosystems. Here, we determined the contribution of emissions from stems of mature black alder (Alnus glutinosa (L.) Gaertn.) to overall CH4 exchange in two temperate peatlands. We measured emissions from stems and soils using closed chambers in a drained and an undrained alder forest over 2 years. Furthermore, we studied the importance of alder leaves as substrate for methanogenesis in an incubation experiment. Stem CH4 emissions were short-lived and occurred only during times of inundation at the undrained site. The drained site did not show stem emissions and the soil acted as a small CH4 sink. The contribution of stem emissions to the overall CH4 budget was below 0.3% in both sites. Our results show that mature black alder can be an intermittent source of CH4 to the atmosphere. However, the low share of stem CH4 emissions in both investigated stands indicates that this pathway may be of minor relative importance in temperate peatlands, yet strongly depend on the hydrologic regime.

7.
Sci Total Environ ; 749: 141571, 2020 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-33370894

RESUMEN

Precipitation is a key factor affecting shallow water table fluctuations. Although the literature on shallow aquifers is vast, groundwater response to precipitation in peatlands has received little attention so far. Characterizing groundwater response to precipitation events in differently managed peatlands can give insight into ecohydrological processes. In this study we determined the groundwater table response rate following precipitation events at a drained and a rewetted fen to characterize the effect of rewetting on hydrological buffer capacity. Multiple regression analysis revealed that the groundwater table at the rewetted fen has more than two times lower rate of response to precipitation events than that of the drained fen, even after adjusting for antecedent groundwater levels. Thus, the rewetted fen delivers a better hydrological buffer function against heavy precipitation events than the drained fen. We found that for the depths at which the groundwater interacts with incoming precipitation, the peat of the rewetted fen has a higher specific yield causing groundwater to rise slower compared to the response at the drained fen. A period of 20 years of rewetting was sufficient to form a new layer of organic material with a significant fraction of macropores providing storage capacity. Long-term rewetting has the potential to create favorable conditions for new peat accumulation, thereby altering water table response. Our study has implications for evaluating the success of restoration measures with respect to hydrological functions of percolation fens.

8.
Microorganisms ; 8(4)2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32290343

RESUMEN

Drained peatlands are significant sources of the greenhouse gas (GHG) carbon dioxide. Rewetting is a proven strategy used to protect carbon stocks; however, it can lead to increased emissions of the potent GHG methane. The response to rewetting of soil microbiomes as drivers of these processes is poorly understood, as are the biotic and abiotic factors that control community composition. We analyzed the pro- and eukaryotic microbiomes of three contrasting pairs of minerotrophic fens subject to decade-long drainage and subsequent long-term rewetting. Abiotic soil properties including moisture, dissolved organic matter, methane fluxes, and ecosystem respiration rates were also determined. The composition of the microbiomes was fen-type-specific, but all rewetted sites showed higher abundances of anaerobic taxa compared to drained sites. Based on multi-variate statistics and network analyses, we identified soil moisture as a major driver of community composition. Furthermore, salinity drove the separation between coastal and freshwater fen communities. Methanogens were more than 10-fold more abundant in rewetted than in drained sites, while their abundance was lowest in the coastal fen, likely due to competition with sulfate reducers. The microbiome compositions were reflected in methane fluxes from the sites. Our results shed light on the factors that structure fen microbiomes via environmental filtering.

9.
Nat Commun ; 11(1): 1644, 2020 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-32242055

RESUMEN

Peatlands are strategic areas for climate change mitigation because of their matchless carbon stocks. Drained peatlands release this carbon to the atmosphere as carbon dioxide (CO2). Peatland rewetting effectively stops these CO2 emissions, but also re-establishes the emission of methane (CH4). Essentially, management must choose between CO2 emissions from drained, or CH4 emissions from rewetted, peatland. This choice must consider radiative effects and atmospheric lifetimes of both gases, with CO2 being a weak but persistent, and CH4 a strong but short-lived, greenhouse gas. The resulting climatic effects are, thus, strongly time-dependent. We used a radiative forcing model to compare forcing dynamics of global scenarios for future peatland management using areal data from the Global Peatland Database. Our results show that CH4 radiative forcing does not undermine the climate change mitigation potential of peatland rewetting. Instead, postponing rewetting increases the long-term warming effect through continued CO2 emissions.

10.
Sci Total Environ ; 721: 137763, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172119

RESUMEN

Peatland restoration is seen as an effective contribution to help achieve the aims of the Paris Agreement because currently huge amounts of peatlands in Northern Central Europe are under unsustainable drainage-based land use. If net zero greenhouse gas emissions from peatlands shall be reached by 2050, restoration measures have to be done as soon as possible. However, rewetting drained peatlands that were under intensive grassland use frequently results in high methane (CH4) emissions, which is often seen as a counter-argument against rewetting. To find the source of high CH4 emissions after rewetting and to explore the best possible way of peatland restoration (i.e., low CH4 emissions after rewetting) under near-natural conditions, we installed a field trial in a drained bog in north-western Germany. The trial consists of seven plots (~8 × 24 m2) representing the status quo-intensive grassland use- and six restoration approaches with combinations of rewetting either on the original surface or after topsoil removal (TSR), biomass harvesting or spreading Sphagnum spp. to initiate vegetation succession. On all seven plots we measured CH4 fluxes using closed chambers. In addition, we investigated CH4 production potential by incubating soil samples and determining methanogen abundance by quantitative PCR. Compared to rewetting on the original surface, CH4 emissions were reduced on TSR plots by factor 30 to 400. Spreading of Sphagnum spp. had only little effect on CH4 emissions during the first year of establishment. TSR also reduced CH4 production potential and methanogen abundance. Further, the response of CH4 fluxes to methanogen abundance was lower after TSR. This suggests that both reduction in labile substrate and in methanogen abundance contribute to near-zero CH4 emissions after TSR. These are the first field-scale results that demonstrate the efficiency of removing degraded topsoil to avoid high CH4 emissions after rewetting.


Asunto(s)
Metano/análisis , Humedales , Dióxido de Carbono/análisis , Europa (Continente) , Alemania , Pradera , Paris , Suelo
11.
Matern Child Nutr ; 14(2): e12561, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29171150

RESUMEN

Emerging evidence suggests that maternal prepregnancy body mass index or weight (MPBW) may be associated with offspring's blood pressure (BP). Therefore, we conducted a systematic review-following the Preferred Reporting Items for Systematic Reviews and Meta-analyses statement-to assess and judge the evidence for an association between MPBW with offspring's later BP. Five data bases were searched without limits. Risk of bias was assessed using the "Tool to Assess Risk of Bias in Cohort Studies," and an evidence grade was allocated following the World Cancer Research Fund criteria. Of 2,011 publications retrieved, 16 studies (all cohort studies) were included in the systematic review; thereof, 5 studies (31%) were rated as good-quality studies. Overall, data from 63,959 participants were enclosed. Systolic BP was analysed in 15 (5 good quality), diastolic BP in 12 (3 good quality), and mean arterial pressure in 3 (no good quality) studies. Five good-quality studies of MPBW with offspring's systolic BP as the outcome and 1 good-quality study with offspring's diastolic BP as the outcome observed a significant association. However, after adding offspring's anthropometry variables to the statistical model, the effect attenuated in 4 studies with systolic BP to nonsignificance, the study with diastolic BP remained significant. No good-quality studies were found with respect to offspring's later mean arterial pressure. In conclusion, this systematic review found suggestive, but still limited, evidence for an association between MPBW with offspring's later BP. The available data suggest that the effect might be mainly mediated via offspring's anthropometry.


Asunto(s)
Presión Sanguínea/fisiología , Índice de Masa Corporal , Peso Corporal/fisiología , Madres , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Adulto Joven
12.
Nutr Cancer ; 67(6): 877-92, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26226486

RESUMEN

Early life, adiposity rebound, and puberty represent critical growth periods when food choices could have long-term relevance for cancer risk. We aimed to relate dietary patterns during these periods to the growth hormone-insulin-like-growth-factor (GH-IGF) axis, insulin resistance, and body fatness in adulthood. Data from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study participants with outcome data at 18-37 years, and ≥2 dietary records during early life (1-2 yr; n = 128), adiposity rebound (4-6 years, n = 179), or puberty (girls 9-14, boys 10-15 yr; n = 213) were used. Dietary patterns at these ages were derived by 1) reduced rank regression (RRR) to explain variation in adult IGF-I, IGF-binding protein-3 (IGFBP-3), homoeostasis model assessment for insulin resistance (HOMA-IR) and fat-mass index; 2) principal component analysis (PCA). Regarding RRR, the patterns "cake/canned fruit/cheese & eggs" (early life), "sweets & dairy" (adiposity rebound) and "high-fat foods" (pubertal boys) were independently associated with higher adult HOMA-IR. Furthermore, the patterns "favorable carbohydrate sources" (early life), "snack & convenience foods" (adiposity rebound), and "traditional & convenience carbohydrates" (pubertal boys) were related to adult IGFBP-3 (P trend < 0.01). PCA identified "healthy" patterns for all periods, but none was associated with the outcomes (P trend > 0.1). In conclusion, dietary patterns during sensitive growth periods may be of long-term relevance for adult insulin resistance and IGFBP-3.


Asunto(s)
Tejido Adiposo/metabolismo , Dieta , Conducta Alimentaria , Resistencia a la Insulina , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias/metabolismo , Adiposidad , Adolescente , Adulto , Composición Corporal , Índice de Masa Corporal , Niño , Fenómenos Fisiológicos Nutricionales Infantiles , Preescolar , Registros de Dieta , Femenino , Humanos , Lactante , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Modelos Lineales , Masculino , Análisis de Componente Principal , Estudios Prospectivos , Pubertad/metabolismo , Adulto Joven
13.
Br J Nutr ; 111(8): 1488-98, 2014 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-24382029

RESUMEN

Primary school years seem to represent a critical period for the development of overweight and obesity. However, only a few studies have analysed the prospective relationship between dietary patterns and weight status in children. The aims of the present study were to identify dietary patterns at the beginning of and during the primary school period and to examine their relevance to the development of body composition. Nutritional and anthropometric data from 371 participants of the Dortmund Nutritional and Longitudinally Designed (DONALD) Study at the beginning (ages 6 and 7 years) and end (ages 10 and 11 years) of the primary school period were used. Principal component analyses (PCA) were conducted to identify dietary patterns, which were regressed on changes in BMI and fat mass index (FMI) between ages 6 and 7 years and ages 10 and 11 years. Reduced rank regression (RRR) was used to directly extract patterns explaining variation in changes in BMI and FMI between ages 6 and 7 years and ages 10 and 11 years. PCA yielded interpretable patterns of dietary changes at the beginning of and during the primary school period, which were not related to changes in body composition. Conversely, RRR allowed identifying predictive patterns: higher baseline intakes of white bread and lower baseline intakes of whole-grain products as well as increases in the consumption of savoury snacks, sausages and cheese during primary school years independently predicted increases in BMI and FMI during the primary school period. In conclusion, selection of unfavourable carbohydrate sources at the beginning of the primary school period and increases in the consumption of processed savoury foods during primary school years may adversely affect the development of body composition during the course of primary school.


Asunto(s)
Tejido Adiposo/metabolismo , Composición Corporal , Índice de Masa Corporal , Dieta , Conducta Alimentaria , Instituciones Académicas , Niño , Femenino , Alemania , Humanos , Masculino , Análisis de Componente Principal , Estudios Prospectivos , Bocadillos
14.
Environ Monit Assess ; 186(4): 2151-8, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24213640

RESUMEN

Closed chamber measurements for methane emission estimation are often carried out with opaque chambers to avoid heating of the headspace. However, mainly in wetlands, some plants possess an internal convective gas transport which quickly responds to changes in irradiation. These plants have also been found to often channel a large part of the released methane in temperate fens. We compare methane fluxes derived from transparent versus opaque chambers on Carex-, Phragmites-, and Typha-dominated stands of a temperate fen. Transparent chamber fluxes almost doubled opaque chamber fluxes in the convective transporting Phragmites stand. In Typha, a trend of higher fluxes determined with the transparent chambers was detectable, whereas in Carex, transparent and opaque chamber fluxes did not differ significantly. Thus, opaque chambers bias the outcome of methane measurements, depending on dominant vegetation. We recommend the use of transparent chambers when determining emissions of convective plants or extrapolating fluxes to larger scales.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Metano/análisis , Poaceae/fisiología , Contaminantes Atmosféricos/metabolismo , Monitoreo del Ambiente/instrumentación , Metano/metabolismo , Humedales
15.
PLoS One ; 8(11): e79436, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24236134

RESUMEN

BACKGROUND: Breastfeeding may lower chronic disease risk by long-term effects on hormonal status and adiposity, but the relations remain uncertain. OBJECTIVE: To prospectively investigate the association of breastfeeding with the growth hormone- (GH) insulin-like growth factor- (IGF) axis, insulin sensitivity, body composition and body fat distribution in younger adulthood (18-37 years). DESIGN: Data from 233 (54% female) participants of a German cohort, the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study, with prospective data on infant feeding were analyzed. Multivariable linear as well as quantile regression were performed with full breastfeeding (not: ≤ 2, short: 3-17, long: >17 weeks) as exposure and adult IGF-I, IGF binding proteins (IGFBP) -1, -2, -3, homeostasis model assessment of insulin resistance (HOMA-IR), fat mass index, fat-free mass index, and waist circumference as outcomes. RESULTS: After adjustment for early life and socio-economic factors, women who had been breastfed longer displayed higher adult IGFBP-2 (p(trend) = 0.02) and lower values of HOMA-IR (p(trend) = 0.004). Furthermore, in women breastfeeding duration was associated with a lower mean fat mass index (p(trend) = 0.01), fat-free mass index (p(trend) = 0.02) and waist circumference (p(trend) = 0.004) in young adulthood. However, there was no relation to IGF-I, IGFBP-1 and IGFBP-3 (all p(trend) > 0.05). Associations for IGFBP-2 and fat mass index were more pronounced at higher, for waist circumference at very low or high percentiles of the distribution. In men, there was no consistent relation of breastfeeding with any outcome. CONCLUSIONS: Our data suggest that breastfeeding may have long-term, favorable effects on extremes of adiposity and insulin metabolism in women, but not in men. In both sexes, breastfeeding does not seem to induce programming of the GH-IGF-axis.


Asunto(s)
Adiposidad , Lactancia Materna , Hormona de Crecimiento Humana/metabolismo , Resistencia a la Insulina , Somatomedinas/metabolismo , Adolescente , Adulto , Composición Corporal , Femenino , Alemania , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Análisis de Regresión , Factores Sexuales , Adulto Joven
16.
J Nutr ; 143(7): 1147-54, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23700336

RESUMEN

Recent studies provide evidence that insulin-like-growth-factor I (IGF-I) and its binding proteins (IGFBP) IGFBP-2 and IGFBP-3 are related to the risk of several common cancers. It remains to be clarified whether their concentrations can be programmed by protein intake from different sources during growth. This study addressed the hypothesis that animal protein intakes during infancy, mid-childhood, and adolescence differ in their relevance for the growth-hormone (GH)-IGF-I axis in young adulthood. Data from the Dortmund Nutritional and Anthropometric Longitudinally Designed Study participants with at least 2 plausible 3-d weighed dietary records during adolescence (age: girls, 9-14 y; boys, 10-15 y; n = 213), around the adiposity rebound (age 4-6 y; n = 179) or early life (age 0.5-2 y; n = 130), and one blood sample in young adulthood were included in the study. Mean serum concentrations of IGF-I, IGFBP-1, IGFBP-2, and IGFBP-3 were compared between tertiles of habitual animal protein intake using multivariable regression analysis. Habitually higher animal protein intakes in females during puberty were related to higher IGF-I (P-trend = 0.005) and IGFBP-3 (P-trend = 0.01) and lower IGFBP-2 (P-trend = 0.04), but not to IGFBP-1 in young adulthood. In turn, IGF-I concentrations in young adulthood were inversely related to animal protein intakes in early life among males only (P-trend = 0.03), but not to animal protein intake around adiposity rebound (P-trend > 0.5). Our data suggest that, among females, a habitually higher animal protein intake during puberty may precipitate an upregulation of the GH-IGF-I axis, which is still discernible in young adulthood. By contrast, among males, higher animal protein intakes in early life may exert a long-term programming of the GH-IGF-I axis.


Asunto(s)
Productos Lácteos , Proteínas en la Dieta/administración & dosificación , Factor I del Crecimiento Similar a la Insulina/fisiología , Carne , Adiposidad , Adolescente , Antropometría , Índice de Masa Corporal , Niño , Preescolar , Registros de Dieta , Femenino , Humanos , Lactante , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Modelos Lineales , Estudios Longitudinales , Masculino , Análisis Multivariante , Estudios Prospectivos
17.
Br J Nutr ; 106(11): 1749-56, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22017962

RESUMEN

Worldwide, the iodisation of salt has clearly improved iodine status. In industrialised countries, iodised salt added to processed food contributes most to iodine supply. Yet it is unclear as to what extent changes in the latter may affect the iodine status of populations. Between 2004 and 2009, 24-h urinary iodine excretions (UIE) were repeatedly measured in 278 German children (6 to 12 years old) of the Dortmund Nutritional and Anthropometric Longitudinally Designed Study (n 707). Na excretion measurements and simultaneously collected 3-d weighed dietary records provided data on intakes of the most important dietary sources of iodine in the children's diet. Actual trends of UIE (2004-9) and contributions of relevant food groups were analysed by mixed linear regression models. Longitudinal regression analysis showed a plateau of UIE in 2004-6; afterwards, UIE significantly decreased till 2009 (P = 0·01; median 24-h UIE in 2004-6: 85·6 µg/d; 2009: 80·4 µg/d). Median urinary iodine concentration fell below the WHO criteria for iodine sufficiency of 100 µg/l in 2007-9. Salt, milk, fish and egg intake (g/d) were significant predictors of UIE (P < 0·005); and the main sources of iodine were salt and milk (48 and 38 %, respectively). The present data hint at a beginning deterioration in the iodine status of German schoolchildren. A decreased use of iodised salt in industrially produced foods may be one possible reason for this development. Because of the generally known risks for cognitive impairment due to even mild iodine deficits in children, a more widespread use of iodised salt, especially in industrially processed foods, has to be promoted.


Asunto(s)
Dieta , Yodo/orina , Niño , Femenino , Alemania , Humanos , Yodo/administración & dosificación , Estudios Longitudinales , Masculino , Análisis de Regresión
18.
Br J Nutr ; 106(3): 345-9, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21736806

RESUMEN

The aim of the present study was to examine the association of pre-pubertal dietary energy density (ED) with both age and body fatness at the start of the pubertal growth spurt (age at take-off, ATO). Analyses included 219 DOrtmund Nutritional and Anthropometric Longitudinally Designed Study participants with sufficient height measurements to estimate ATO who provided 3 d weighed dietary records at baseline, i.e. 2 and 3 years before ATO (mean age 6·9 (SD 1·2) years). Mean energy intakes and amounts of foods/drinks consumed at baseline were derived from the records. ED (kJ/g) was calculated based on (1) all foods and drinks (ED_all), (2) foods and energy-containing drinks (ED_energy), (3) foods and milk as a drink, but no other beverages (ED_milk) and (4) foods only, solid or liquid (ED_food). Using multiple regression analyses, the association between the ED variables and ATO was investigated. Furthermore, Z-scores of BMI and fat mass index (FMI) at ATO were considered as outcomes to reflect body fatness at puberty onset. The results showed that ED at baseline was not associated with ATO, regardless of the ED method used. For example, mean ATO in the lowest v. highest tertile of ED_food was 9·3 (95 % CI 9·0, 9·5) v. 9·4 (95 % CI 9·1, 9·7) years, P(trend) = 0·8 (adjusted for sex, maternal age, birth weight, dietary protein, dietary fibre, baseline BMI Z-score). Similarly, ED was not independently associated with BMI or FMI Z-score at ATO (P(trend) = 0·3-0·9). In conclusion, dietary ED in childhood did not influence timing or body fatness at ATO in this cohort of healthy, free-living children.


Asunto(s)
Adiposidad , Índice de Masa Corporal , Dieta , Ingestión de Energía , Crecimiento , Pubertad , Composición Corporal , Niño , Preescolar , Registros de Dieta , Femenino , Humanos , Estudios Longitudinales , Masculino , Análisis de Regresión
19.
Circulation ; 123(13): 1410-7, 2011 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-21422385

RESUMEN

BACKGROUND: We have shown that adherence to the Dietary Approaches to Stop Hypertension (DASH) diet is related to blood pressure in youth with type 1 and type 2 diabetes mellitus. We explored the impact of the DASH diet on other cardiovascular disease risk factors. METHODS AND RESULTS: Between 2001 and 2005, data on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, low-density lipoprotein particle density, apolipoprotein B, body mass index, waist circumference, and adipocytokines were ascertained in 2130 youth aged 10 to 22 years with physician-diagnosed diabetes mellitus. Dietary intake was assessed by food frequency questionnaire, categorized into the DASH food groups, and assigned an adherence score. Among youth with type 1 diabetes mellitus, higher adherence to the DASH diet was significantly and inversely associated with low-density lipoprotein/high-density lipoprotein ratio and A(1c) in multivariable-adjusted models. Youth in the highest adherence tertile had an estimated 0.07 lower low-density lipoprotein/high-density lipoprotein ratio and 0.2 lower A(1c) levels than those in the lowest tertile adjusted for confounders. No significant associations were observed with triglycerides, low-density lipoprotein particle density, adipocytokines, apolipoprotein B, body mass index Z score, or waist circumference. Among youth with type 2 diabetes mellitus, associations were observed with low-density lipoprotein particle density and body mass index Z score. CONCLUSIONS: The DASH dietary pattern may be beneficial in the prevention and management of cardiovascular disease risk in youth with diabetes mellitus.


Asunto(s)
Diabetes Mellitus Tipo 1/dietoterapia , Diabetes Mellitus Tipo 2/dietoterapia , Dieta Hiposódica/métodos , Adolescente , Factores de Edad , Niño , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Diabetes Mellitus/sangre , Diabetes Mellitus/dietoterapia , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Humanos , Hipertensión/sangre , Hipertensión/dietoterapia , Hipertensión/etiología , Masculino , Factores de Riesgo , Adulto Joven
20.
Am J Hum Biol ; 23(2): 216-24, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21319251

RESUMEN

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.


Asunto(s)
Desarrollo del Adolescente , Composición Corporal , Desarrollo Infantil , Pubertad , Adolescente , Adulto , Factores de Edad , Índice de Masa Corporal , Niño , Femenino , Alemania , Humanos , Estudios Longitudinales , Masculino , Modelos Estadísticos , Estudios Prospectivos , Factores Sexuales
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