O impacto do excesso de gordura corporal sobre a remodelação óssea de adolescentes

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Obesity markers and blood pressure in a sample of Portuguese children and adolescents.

Little information exists regarding the effect of several obesity markers on blood pressure (BP) levels in youth. Transverse study including 2494 boys and 2589 girls. Height, weight and waist were measured according to the international criteria and body fat (BF) by bioimpedance. BP was measured by an automated device. Hypertension was defined using sex-specific, age-specific and height-specific observation-points. Body mass index (BMI) and waist were positively related with systolic blood pressure (SBP) and diastolic blood pressure (DBP) and heart rate in both sexes, whereas the relationships with BF were less consistent. Stepwise linear regression analysis showed that BMI was positively related with SBP and DBP in both sexes, whereas BF was negatively related with SBP in both sexes and with heart rate in boys only; finally, waist was positively related with SBP in boys and heart rate in girls. Age and heart rate-adjusted values of SBP and DBP increased with BMI: for SBP, 117+/-1, 123+/-1 and 124+/-1 mmHg in normal, overweight and obese boys, respectively; corresponding values for girls were 111+/-1, 114+/-1 and 116+/-2 mmHg (mean+/-SE, P<0.001). Overweight and obese boys had an odds ratio for being hypertensive of 2.26 (95% confidence interval: 1.79-2.86) and 3.36 (2.32-4.87), respectively; corresponding values for girls were 1.58 (confidence interval 1.25-1.99) and 2.31 (1.53-3.50). BMI, not BF or waist, is consistently and independently related to BP levels in children; overweight and obesity considerably increase the risk of hypertension.

Relative importance of body composition, osteoporosis- related behaviours and socioeconomic status on bone SOS in adolescent females

The purpose of this study was to examine the associations between bone speed of sound (SOS) and body composition, osteoporosis-related health behaviours, and socioeconomic status (SES) in adolescent females. A total of 442 adolescent females in grades 9-11 participated. Anthropometric measures of height, body mass, and percent body fat were taken, and osteo-protective behaviours such as oral contraceptive use (OC), physical activity and daily calcium intake were evaluated using self-report questionnaires. Bone SOS was measured by transaxial quantitative ultrasound (QUS) at the distal radius and mid-tibia. The results suggest that fat mass is a significant negative predictor of tibial SOS, while lean mass is positively associated with radial SOS scores and calcium intake was positively associated with tibial SOS scores (pfat mass, and influenced positively by OC use, calcium intake and lean mass.

Association between diet quality and metabolic syndrome in overweight and obese postmenopausal women

Résumé Objectifs : Le syndrome métabolique (MetS) est un ensemble de composantes (obésité, résistance à l'insuline, intolérance au glucose, dyslipidémie, hypertension) qui sont associées à une augmentation du risque de diabète de type 2 et de maladies cardiovasculaires. Aux États-Unis, la fréquence du MetS atteint des proportions épidémiques avec une prévalence de 25% de la population. Les études nutritionnelles traditionnelles se sont concentrées sur l’effet d’un nutriment alors que les études plus récentes ont déterminé l’effet global de la qualité alimentaire sur les facteurs de risque. Cependant, peu d'études ont examiné la relation entre la qualité alimentaire et le MetS. Objectif: Déterminer l'association entre la qualité alimentaire et le MetS et ses composantes. Méthodes: La présence du MetS a été déterminée chez 88 femmes post-ménopausées en surpoids ou obèses, selon la définition du National Cholesterol Education Program Adult treatment Panel III alors que la qualité alimentaire a été évaluée selon le Healthy Eating Index (HEI). La sensibilité à l’insuline, la composition corporelle et le métabolisme énergétique ont été mesurés. Résultats: Le HEI corrélait négativement avec la plupart des mesures de masse grasse et du poids mais pas avec la sensibilité à l'insuline, l’hypertension et la plupart des marqueurs lipidiques. Cependant, l’HEI corrélait positivement avec LDL-C/ApoB et négativement avec le métabolisme énergétique. Conclusion: Les résultats démontrent que l’HEI est associé avec les mesures de gras corporel et la grosseur des LDL. Mots clés: Obésité, qualité alimentaire, métabolisme lipidique, syndrome métabolique.

Proyecto de autoejercitación

Desde mi experiencia como educador físico y futuro especialista en ejercicio físico para la salud, pongo especial atención en los hábitos de vida de las personas, con el objetivo de poder orientarles en un plan de ejercicios que redunden en su salud y bienestar. Sin embargo, para la presente investigación, centraré la atención en mis propios hábitos de vida, particularmente en lo referido a nutrición y actividad física, la cual presenta actualmente una tendencia hacia la disminución del movimiento en mi vida cotidiana, aspecto bastante cuestionable teniendo en cuenta el campo de mi especialización. A partir de esta perspectiva, surge entonces la idea de realizar un programa de auto ejercitación, a la luz de los conocimientos adquiridos en la especialización y poniendo a prueba los postulados estudiados, para convertirme en el sujeto de mi propia investigación, con el objetivo de modificar conductas erróneas, atreverme a buscar un estilo de vida saludable y ganar así, una mayor experiencia en mi futura labor como especialista en ejercicio físico para la salud.

Análisis en componentes principales de la Obesidad-Adiposidad y su asociación con factores de riesgo cardiometabólico en mujeres. Estudio transversal en un entorno laboral

Los factores de riesgo para el desarrollo de eventos cardiometabólicos, constituyen un set de variables útiles como predictores de enfermedades cardiovasculares y metabólicas. Uno de los factores de riesgo que recibe mayor atención en la deteccion y prevencion de eventos cardiometabolicos, es la obesidad y la herramienta más común para diagnosticarla es el índice de masa corporal. Sin embargo, existen imprecisiones y sesgos en su concepto actual y en la forma de medirla. Nuevas alternativas de valoracion y tamizaje deben incluir porcentaje de grasa corporal y su distribución, dada la relevancia que adquiere la adiposidad en la definicion de obesidad y por ende en la mejoría del pronóstico de eventos cardiometabólicos. Los entornos laborales son ambientes vulnerables que se beneficiarían ampliamente de la aplicación de estas nuevas alternativas para predecir e intervenir tempranamente el riesgo cardiometabólico desde el correcto tamizaje de obesidad, dado el volumen poblacional que se puede abordar.

Valores del índice cintura/cadera en población escolar de Bogotá, Colombia: Estudio

Objetivo: Determinar los valores del índice cintura/cadera (ICC) en una población escolar de Bogotá, Colombia, pertenecientes al estudio FUPRECOL. Métodos: Estudio descriptivo y transversal, realizado en 3.005 niños y 2.916 adolescentes de entre 9 y 17,9 años de edad, pertenecientes a 24 instituciones educativas oficiales de Bogotá, Colombia. Se tomaron medidas de peso, talla, circunferencia de cintura, circunferencia de cadera. El estado de maduración sexual se recogió por auto-reporte. Se calcularon los percentiles (P3, P10, P25, P50, P75, P90 y P97) según sexo y edad y se realizó una comparación entre los valores del ICC observados con estándares internacionales. Resultados: De la población general (n=5.921), el 57,0% eran mujeres (promedio de edad 12,7 ± 2,3 años). En todas las edades el ICC fue mayor en los varones que en las mujeres, observándose un descenso en la media de los valores obtenidos desde los 9 hasta los 17,9 años. En varones, los valores del ICC mayores del P90 (asociados a riesgo cardiovascular) estuvieron en el rango 0,87 y 0,93 y en las mujeres entre 0,85 y 0,89. Al comparar los resultados de este estudio, por grupos de edad y sexo, con trabajos internacionales de niños y adolescentes de Europa, Suramérica, Asia y África, se observa que los valores del ICC fueron menores en este estudio en ambos sexos, con excepción de los escolares originarios de Grecia y Venezuela. Conclusiones: Se presentan percentiles del ICC según edad y sexo que podrán ser usados de referencia en la evaluación del estado nutricional y en la predicción del riesgo cardiovascular desde edades tempranas en población de Bogotá, Colombia.

Benefícios de uma intervenção com uma dieta do tipo mediterrânico e um programa de exercício físico em variáveis de composição corporal e factores de risco de doença cardiovascular

Introdução: Uma dieta do tipo mediterrânico associada a exercício físico pode ser uma estratégia eficaz na prevenção da obesidade e de co-morbilidades associadas. Objectivo: Este estudo pretendeu determinar a associação entre um programa de intervenção, constituído por uma dieta do tipo mediterrânico e exercício físico, com alterações em variáveis de composição corporal e metabólicas. Método: 12 mulheres e homens sedentários (32,5±8,74 anos, 1,69±0,11 cm), com excesso de peso (81,9±18,1 kg, 28,5±5,45 kg/m2, 36,1±8,56 % massa gorda) participaram num programa de intervenção de 12 semanas. Foi realizada avaliação da composição corporal, do dispêndio energético, da ingestão energética e de níveis séricos de lípidos em jejum. As sessões de nutrição foram realizadas semanalmente e a dieta apresentou uma distribuição de macronutrientes correspondente a 40-45% de hidratos de carbono, 15-20% de proteína e 30-35% de lípidos. As sessões de exercício foram realizadas 3 vezes por semana, com prescrição para as componentes cardiovascular e de força. Resultados: Os participantes tiveram alterações significativas nas variáveis de peso, perímetro da cintura, massa gorda, dispêndio energético e níveis séricos de colesterol e triglicéridos (p<0,05). A distribuição de macronutrientes da dieta não se alterou com a intervenção alimentar, contudo, o aumento significativo do consumo de PUFA’s revelou-se associado a menores valores de massa gorda e a maiores diferenças nos níveis de triglicéridos (p<0,05). Conclusão: O dispêndio calórico e o consumo de PUFA’s revelaram estar associados a melhorias da composição corporal (massa gorda). Este estudo também conduziu à melhoria das concentrações de colesterol e triglicéridos. No entanto, as melhorias nas concentrações de triglicéridos associaram-se apenas à dieta.

Lack of association between central adiposity and lipaemia in UK Sikh men

OBJECTIVE: To determine whether the positive statistical associations between measures of total and regional adiposity and measures of glucose, insulin and triacylglycerol ( TAG) metabolism reported in Caucasian men, are also observed in UK Sikhs. DESIGN: A matched cross-sectional study in which each volunteer provided a blood sample after a 12-h overnight fast and had anthropometric measurements taken. SUBJECTS: A total of 55 healthy Caucasian and 55 healthy UK Sikh men were recruited. The Caucasian and Sikh men were matched for age ( 48.7 +/- 10.9 and 48.3 +/- 10.0 y, respectively) and body mass index (BMI) ( 26.1 +/- 2.8 and 26.3 +/- 3.2 kg/m(2), respectively). MEASUREMENTS: Anthropometric measurements were performed to assess total and regional fat depots. The concentrations of plasma total cholesterol, high-density cholesterol (HDL- C), low-density cholesterol (LDL-C) and small dense LDL (LDL3), TAG, glucose, fasting insulin (ins) and nonesterified fatty acids (NEFA) were analysed in fasted plasma. Surrogate measures of insulin resistance (HOMA-IR) and insulin sensitivity (RQUICKI) were calculated from insulin and glucose (HOMA-IR) and insulin, glucose and NEFA ( RQUICKI) measurements. RESULTS: The Sikh men had significantly higher body fat, with the sum of the four skinfold measurements (Ssk) ( P = 0.0001) and subscapular skinfold value (P = 0.009) higher compared with the Caucasian men. The Sikh volunteers also had characteristics of the metabolic syndrome: lower HDL-C (P = 0.07), higher TAG (P = 0.004), higher % LDL3 (P = 0.0001) and insulin resistance (P = 0.05). Both ethnic groups demonstrated positive correlations between insulin and waist circumference (Caucasian: r = 0.661, P = 0.0001; Sikh: r = 0.477, P = 0.0001). The Caucasian men also demonstrated significant positive correlations between central adiposity (r = 0.275, P = 0.04), other measures of adiposity (BMI and suprailiac skinfold) and plasma TAG, whereas the Sikh men showed no correlation for central adiposity (r = 0.019, ns) and TAG with a trend to a negative relationship between other measures ( Ssk and suprailiac) which reached near significance for subscapular skinfold and TAG (r = - 0.246, P = 0.007). The expected positive association between insulin and TAG was observed in the Caucasian men (r = 0.318, P = 0.04) but not in the Sikh men (r = 0.011, ns). CONCLUSIONS: In the Caucasian men, the expected positive association between plasma TAG and centralized body fat was observed. However, a lack of association between centralized, or any other measure of adiposity, and plasma TAG was observed in the matched Sikh men, although both ethnic groups showed the positive association between centralized body fat and insulin resistance, which was less strong for Sikhs. These findings in the Sikh men were not consistent with the hypothesis that there is a clear causal relationship between body fat and its distribution, insulin resistance, and lipid abnormalities associated with the metabolic syndrome, in this ethnic group.

Adiposity, insulin and lipid metabolism in post-menopausal women

OBJECTIVE: To investigate relationships between body fat and its distribution and carbohydrate and lipid tolerance using statistical comparisons in post-menopausal women. DESIGN: Sequential meal, postprandial study (600 min) which included a mixed standard breakfast (30 g fat) and lunch (44 g fat) given at 0 and 270 min, respectively, after an overnight fast. SUBJECTS: Twenty-eight post-menopausal women with a diverse range of body weight (body mass index (BMI), mean 27.2, range 20.5-38.8 kg/m2) and abdominal fat deposition (waist, mean 86.4, range 63.5-124.0 cm). Women with BMI <18 or >37 kg/m2, age>80 y and taking hormone replacement therapy (HRT) were excluded. MEASUREMENTS: Anthropometric measurements were performed to assess total and regional fat deposits. The concentrations of plasma total cholesterol, high density lipoprotein (HDL) cholesterol, triacylglycerol (TAG), glucose, insulin (ins), non-esterified fatty acids (NEFA) and apolipoprotein (apo) B-48 were analysed in plasma collected at baseline (fasted state) and at 13 postprandial time points for a 600 min period. RESULTS: Insulin concentrations in the fasted and fed state were significantly correlated with all measures of adiposity (BMI, waist, waist-hip ratio (W/H), waist-height ratio (W/Ht) and sum of skinfold thickness (SSk)). After controlling for BMI, waist remained significantly and positively associated with fasted insulin (r=0.559) with waist contributing 53% to the variability after multiple regression analysis. After controlling for waist, BMI remained significantly correlated with postprandial (IAUC) insulin (r=0.535) contributing 66% of the variability of this measurement. No association was found between any measures of adiposity and glucose concentrations, although insulin concentration in relation to glucose concentration (glucose-insulin ratio) was significantly negatively correlated with all measures of adiposity. A significant positive correlation was found between fasted TAG and BMI (r=0.416), waist (r=0.393) and Ssk (r=0.457) and postprandial (AUC) TAG with BMI (r=0.385) and Ssk (r=0.406). A significantly higher postprandial apolipoprotein (apo) B-48 response was observed in those women with high BMI (>27 kg/m2). Fasting levels of NEFA were significantly and positively correlated with all measures of adiposity (except W/H). No association was found between cholesterol containing particles and any measure of adiposity. CONCLUSION: Hyperinsulinaemia associated with increasing body fat and central fat distribution is associated with normal glucose but not TAG or NEFA concentrations in postmenopausal women.

Lack of association between lipaemia and central adiposity in subjects with an atherogenic lipoprotein phenotype (ALP)

OBJECTIVE: To investigate the associations between indices of adiposity and cardiovascular risk factors in individuals with an atherogenic lipoprotein phenotype (ALP). SUBJECTS: Fifty-five men, aged 34-69 y, body mass index (BMI) 22-35 kg/m2, with an ALP lipid profile (triglycerides (TG) 1.5-4.0 mmol/l, HDL<1.1 mmol/l; %LDL-3>40% total LDL). DESIGN: Each participant provided a fasting blood sample and underwent an 8 h postprandial assessment and had anthropometric measurements taken. OUTCOME MEASURES: BMI, waist circumference (W), waist-to-hip ratio (W/H), sum of skinfolds (SSK), fasting and postprandial concentrations of glucose, insulin and plasma lipids, post-heparin lipase activity, and apoE genotype. RESULTS: The expected positive associations between BMI, W and SSK and fasting and postprandial insulin were observed (r=0.42-0.65). Little association between glucose responses and any measures of adiposity was evident. Unexpectedly, there were no positive associations between measures of central adiposity (W and W/H) and fasting and postprandial TG responses, with a trend towards negative associations in this study group (TG AUC vs W, r=-0.23, P=0.097; TG IAUC vs W/H, r=-0.26, P=0.068). Subgroup analysis indicated that lack of a positive association between central adiposity and postprandial TG values was more evident in those with one E4 allele (r=-0.42, P=0.077) relative to non-E4 carriers (r=-0.16, P=0.430). The expected positive associations between insulin and TG responses were not observed (r=-0.03 to -0.36). CONCLUSION: In this ALP group the expected positive association between TG responses and a centralized distribution of body fat was not observed, particularly in individuals with an apoE4 genotype. Our findings are not in line with the view that there is a clear causal relationship between insulin resistance and the lipid abnormalities associated with ALP.

Variation in the FFAR1 gene modifies BMI, body composition and plasma lipids but not plasma insulin or Beta-cell function in overweight subjects

Background FFAR1 receptor is a long chain fatty acid G-protein coupled receptor which is expressed widely, but found in high density in the pancreas and central nervous system. It has been suggested that FFAR1 may play a role in insulin sensitivity, lipotoxicity and is associated with type 2 diabetes. Here we investigate the effect of three common SNPs of FFAR1 (rs2301151; rs16970264; rs1573611) on pancreatic function, BMI, body composition and plasma lipids. Methodology/Principal Findings For this enquiry we used the baseline RISCK data, which provides a cohort of overweight subjects at increased cardiometabolic risk with detailed phenotyping. The key findings were SNPs of the FFAR1 gene region were associated with differences in body composition and lipids, and the effects of the 3 SNPs combined were cumulative on BMI, body composition and total cholesterol. The effects on BMI and body fat were predominantly mediated by rs1573611 (1.06 kg/m2 higher (P = 0.009) BMI and 1.53% higher (P = 0.002) body fat per C allele). Differences in plasma lipids were also associated with the BMI-increasing allele of rs2301151 including higher total cholesterol (0.2 mmol/L per G allele, P = 0.01) and with the variant A allele of rs16970264 associated with lower total (0.3 mmol/L, P = 0.02) and LDL (0.2 mmol/L, P<0.05) cholesterol, but also with lower HDL-cholesterol (0.09 mmol/L, P<0.05) although the difference was not apparent when controlling for multiple testing. There were no statistically significant effects of the three SNPs on insulin sensitivity or beta cell function. However accumulated risk allele showed a lower beta cell function on increasing plasma fatty acids with a carbon chain greater than six. Conclusions/Significance Differences in body composition and lipids associated with common SNPs in the FFAR1 gene were apparently not mediated by changes in insulin sensitivity or beta-cell function.

Differential effects of two fermentable carbohydrates on central appetite regulation and body composition

BACKGROUND: Obesity is rising at an alarming rate globally. Different fermentable carbohydrates have been shown to reduce obesity. The aim of the present study was to investigate if two different fermentable carbohydrates (inulin and b-glucan) exert similar effects on body composition and central appetite regulation in high fat fed mice. METHODOLOGY/PRINCIPAL FINDINGS: Thirty six C57BL/6 male mice were randomized and maintained for 8 weeks on a high fat diet containing 0% (w/w) fermentable carbohydrate, 10% (w/w) inulin or 10% (w/w) b-glucan individually. Fecal and cecal microbial changes were measured using fluorescent in situ hybridization, fecal metabolic profiling was obtained by proton nuclear magnetic resonance (1H NMR), colonic short chain fatty acids were measured by gas chromatography, body composition and hypothalamic neuronal activation were measured using magnetic resonance imaging (MRI) and manganese enhanced MRI (MEMRI), respectively, PYY (peptide YY) concentration was determined by radioimmunoassay, adipocyte cell size and number were also measured. Both inulin and b-glucan fed groups revealed significantly lower cumulative body weight gain compared with high fat controls. Energy intake was significantly lower in b-glucan than inulin fed mice, with the latter having the greatest effect on total adipose tissue content. Both groups also showed an increase in the numbers of Bifidobacterium and Lactobacillus-Enterococcus in cecal contents as well as feces. b- glucan appeared to have marked effects on suppressing MEMRI associated neuronal signals in the arcuate nucleus, ventromedial hypothalamus, paraventricular nucleus, periventricular nucleus and the nucleus of the tractus solitarius, suggesting a satiated state. CONCLUSIONS/SIGNIFICANCE: Although both fermentable carbohydrates are protective against increased body weight gain, the lower body fat content induced by inulin may be metabolically advantageous. b-glucan appears to suppress neuronal activity in the hypothalamic appetite centers. Differential effects of fermentable carbohydrates open new possibilities for nutritionally targeting appetite regulation and body composition.

Obesity, diabetes and longevity in the Gulf: is there a Gulf Metabolic Syndrome?

The Gulf is experiencing a pandemic of lifestyle-induced obesity and type 2 diabetes mellitus (T2DM), with rates exceeding 50 and 30%, respectively. It is likely that T2DM represents the tip of a very large metabolic syndrome iceberg, which precedes T2DM by many years and is associated with abnormal/ectopic fat distribution, pathological systemic oxidative stress and inflammation. However, the definitions are still evolving with the role of different fat depots being critical. Hormetic stimuli, which include exercise, calorie restriction, temperature extremes, dehydration and even some dietary components (such as plant polyphenols), may well modulate fat deposition. All induce physiological levels of oxidative stress, which results in mitochondrial biogenesis and increased anti-oxidant capacity, improving metabolic flexibility and the ability to deal with lipids. We propose that the Gulf Metabolic Syndrome results from an unusually rapid loss of hormetic stimuli within an epigenetically important time frame of 2-3 generations. Epigenetics indicates that thriftiness can be programmed by the environment and passed down through several generations. Thus this loss of hormesis can result in continuation of metabolic inflexibility, with mothers exposing the foetus to a milieu that perpetuates a stressed epigenotype. As the metabolic syndrome increases oxidative stress and reduces life expectancy, a better descriptor may therefore be the Lifestyle-Induced Metabolic Inflexibility and accelerated AGEing syndrome – LIMIT-AGE. As life expectancy in the Gulf begins to fall, with perhaps a third of this life being unhealthy – including premature loss of sexual function, it is vital to detect evidence of this condition as early in life as possible. One effective way to do this is by detecting evidence of metabolic inflexibility by studying body fat content and distribution by magnetic resonance (MR). The Gulf Metabolic Syndrome thus represents an accelerated form of the metabolic syndrome induced by the unprecedented rapidity of lifestyle change in the region, the stress of which is being passed from generation to generation and may be accumulative. The fundamental cause is probably due to a rapid increase in countrywide wealth. This has benefited most socioeconomic groups, resulting in the development of an obesogenic environment as the result of the rapid adoption of Western labour saving and stress relieving devices (e.g. cars and air conditioning), as well as the associated high calorie diet.

Walking in a winter wonderland? Strategies for Early and Middle Pleistocene survival in mid-latitude Europe

Any occupation of northern Europe by Lower Palaeolithic hominins, even those occurring during full interglacials, must have addressed the challenges of marked seasonality and cold winters. These would have included the problems of: wind-chill and frostbite; duration, distribution and depth of snow-cover; reduced daylight hours; and distribution and availability of animal and plant foods. Solutions can essentially be characterised as a ‘stick or twist’ choice: i.e. year-round presence on a local scale vs. extensive annual mobility. However these options, and the ‘interim’ strategies that lie between them, present various problems, including maintaining core body temperature, meeting the energetic demands of mobility, coping with reduced resource availability and increasing patchiness, and meeting nutritional requirements. The feasibility of different winter survival strategies are explored with reference to Lower Palaeolithic palaeoenvironmental reconstructions and on-site behavioural evidence. Emphasis is placed upon possible strategies for (i) avoiding the excessive lean meat protein problem of ‘rabbit starvation’ (e.g. through exploitation of ‘residential’ species with significant winter body fat and/or by targeting specific body parts, following modern ethnographic examples, supplemented by the exploitation of winter plants); and (ii) maintaining body temperatures (e.g. through managed pyrotechnology, and/or other forms of cultural insulation). The paper concludes with a suggested winter strategy.