[Evidence of social support as therapy for weight loss: a systematic review]. / Evidencias del soporte social como terapia para la pérdida de peso: una revisión sistemática.

INTRODUCTION: Social Support (SS) therapy can be an effective method of weight loss compared with conventional treatment (CT). OBJECTIVE: To evaluate RCT's using SS therapy on weight in subjects with overweight or obesity. METHODOLOGY: We reviewed all original articles published in MEDLINE/PubMed, SciELO, EBSCO, Google Scholar, from 2000 to August 2011, and one referred in a previous metanalisis, of RCT's of the effect of SS therapy on weight loss, with at least five months of treatment, compared with another therapy or a CT. RESULTS: Eight articles were analyzed. It was observed heterogeneity in the design, differences in the components of the interventions, and cultural characteristics of the population. The difference between groups in weight loss in five out of seven studies, ranged from 2.3 kg (24 m) to 8.3 kg (12 m). However, the treatment in the control groups did not meet the accepted recommended guidelines. There was no allocation concealment in two studies, and no blindness in four. Most studies showed large dispersion in the results. Therefore, the quality of the evidence is low. CONCLUSIONS: These results warrant further and better design and longer term studies to generate higher quality evidence.

[Intervention programs to promote physical activity in school children: systematic review]. / Programas de intervención para la promoción de actividad física en niños escolares: revisión sistemática.

OBJECTIVE: The purpose of this systematic review was to assess physical activity promotion programs in school children from 6 to 12 years old. METHODS: Randomized and non-randomized controlled trials of physical activity studies with an intervention period equal to or more than 12 months, published in the databases of MEDLINE/PubMed, SciELO, EBSCO and SPORTDiscus through may 2010 were searched. RESULTS: Seven studies were analyzed. Overall, the study design, the follow-up periods, the ethnic characteristics of the population, and the instruments used to evaluate the interventions were heterogeneous. The outcomes showed moderate impact of intervention programs to increase the physical activity in children and adolescents. In two of the studies was observed an increase in the physical activity and in five of the studies no significant difference in the physical activity assessed with accelerometers and pedometers. CONCLUSION: In five out of seven studies it was not shown statistical differences in cpm, including the longest experimental study. These results suggest the need of designing studies including modifications in different environments.

Effect of a low glycemic load on body composition and Homeostasis Model Assessment (HOMA) in overweight and obese subjects.

OBJECTIVE: The aim of this study was to compare the effects of different glycemic load diets on biochemical data and body composition, in overweight and obese subjects, during a 6-month period. RESEARCH DESIGN AND METHODS: This study was an experimental, randomized, parallel design. Anthropometric measurements and biochemical data were measured at baseline at 3 and at 6 months. All subjects completed 3-day dietary intake diaries at the baseline period and during the third and the sixth months. At the sixth month, LGL group had a mean intake of 1,360 ± 300 kcal/day and the high glycemic load group (HGL) had a mean intake of 1,544 ± 595 kcal/day. RESULTS: LGL group obtained a weight reduction of 4.5% (p = 0.006) and the HGL group of 3.0% (p = 0.18). Significant reductions in waist circumference (5%, p = 0.001) of the LGL group were observed, 10% of body fat percentage (p = 0.001), 4.3 kg (13%) of body fat (p = 0.001), 14% of total cholesterol (p=0.007), 35% of high-density lipoproteins (HDL) (p = 0.001), and 10% of HOMA (p = 0.009). In the HGL group, reductions of 4.5% of waist circumference (p = 0.02), 37% of HDL (p = 0.002), and an increase of 8 % of LDL (p = 0.04) were observed. CONCLUSIONS: These results suggest that long term LGL diets are more effective for reducing body mass index, body fat, waist circumference and HOMA and, therefore, may contribute in the prevention of diabetes.

Effect of a low glycemic load on body composition and Homeostasis Model Assessment (HOMA) in overweight and obese subjects / Efecto de la baja carga clucémica en la composición corporal y el HOMA en sujetos con sobrepeso y obesidad

Objective: The aim of this study was to compare the effects of different glycemic load diets on biochemicaldata and body composition, in overweight and obese subjects,during a 6-month period.Research design and methods: This study was an experimental, randomized, parallel design. Anthropometric measurements and biochemical data were measuredat baseline at 3 and at 6 months. All subjects completed 3-day dietary intake diaries at the baseline period and during the third and the sixth months. At the sixthmonth, LGL group had a mean intake of 1,360 ± 300kcal/day and the high glycemic load group (HGL) had amean intake of 1,544 ± 595 kcal/day.Results: LGL group obtained a weight reduction of4.5% (p = 0.006) and the HGL group of 3.0% (p = 0.18). Significant reductions in waist circumference (5%, p =0.001) of the LGL group were observed, 10% of body fat percentage (p = 0.001), 4.3 kg (13%) of body fat (p =0.001), 14% of total cholesterol (p=0.007), 35% of highdensity lipoproteins (HDL) (p = 0.001), and 10% ofHOMA (p = 0.009). In the HGL group, reductions of4.5% of waist circumference (p = 0.02), 37% of HDL (p =0.002), and an increase of 8 % of LDL (p = 0.04) were observed.Conclusions: These results suggest that long term LGL diets are more effective for reducing body mass index, body fat, waist circumference and HOMA and, therefore,may contribute in the prevention of diabetes (AU)

Objetivo: Comparar el efecto de dietas con diferente carga glucémica en la composición corporal y los marcadores bioquímicos, en sujetos con sobrepeso u obesidad, durante un periodo de seis meses.Metodología: Estudio experimental, aleatorio, paralelo.Se realizaron mediciones antropométricas y bioquímicasal inicio, a los tres y a los seis meses. Todos los sujetos realizaron un registro de alimentos de tres días, al inicio, a los tres y a los seis meses. A los seis meses, el grupo de dieta de baja carga glucémica (DBCG) tuvo una ingesta energética promedio de 1.360 ± 300 kcal/día, y el grupo con alta carga glucémica (DACG) de 1.544 ± 595kcal/día. Resultados: El grupo con DBCG obtuvo una reducción de peso del 4,5% (p = 0,006) y el grupo con DACG del3,0% (p = 0,18). En el grupo con DBCG se observaron reducciones significativas en la circunferencia de cintura(CC) (5%, p = 0,001), 10% en el porcentaje de grasa corporal(p = 0,001), 4,3 kg (13%) de masa grasa (p = 0,001),14% en el colesterol total (p = 0,007), 35% en las lipoproteínasde alta densidad (HDL) (p = 0,001), y un 10% en el HOMA (p = 0,009). En el grupo con DACG se observaron reducciones del 4,5% en la CC (p = 0,02), 37% en las HDL(p = 0,002), y un incremento en las lipoproteínas de alta densidad (LDL) del 8% (p = 0,04).Conclusiones: Estos resultados sugieren que a largo plazo las DBCG son más efectivas en la reducción del índice de masa corporal, la grasa corporal, la CC y la sensibilidad a la insulina (HOMA), lo que puede contribuir en la prevención de la diabetes (AU)

[Effectivity in the use of protein supplements in resistance training: systematic review]. / Efectividad del uso de suplementos de proteína en entrenamientos de fuerza: revisión sistemática.

To increase strength and lean body mass, protein has become one of the most popular supplements among athletes. The aim of this study was to analyze the effect of protein supplementation on body composition. A systematic review of the randomized controlled trials (RCT), published in MEDLINE/PubMed and SciELO up to April 10, 2009, was conducted. All RCT conducted in healthy subjects with interventions of six or more weeks were included. Nine studies fulfilled the inclusion criteria, and three of them had level 3 of evidence. Among these studies, the increase of lean mass ranged from 0.8 to 1.9 kg. However, the study with the longest term had duration of 12 weeks. Therefore, the evidence does not support the recommendation for the consumption of protein supplements among healthy individuals.

[Review of controled clinical trials of behavioral treatment for obesity]. / Revisión de ensayos clínicos controlados mediante cambios en el comportamiento para el tratamiento de la obesidad.

The increased prevalence of obesity has been associated to an increment in chronic-degenerative diseases. The behavioral conduct therapies (BCT) have been used to help subjects develop a series of skills to reach a healthy weight. We conducted a review of the literature of BCT from controlled clinical trials registered at PubMed from January 2000 to november 2006. We found five long-term (> or = 12 months) studies and analyzed each study. The percent of weight loss at the end of follow up ranged from 3% to 9% of the initial weight; the percent of retention fluctuated from 92% at three months to 55% at 24 months. There were no similar reported studies conducted in Latino or Hispanic population. These results suggest that the change in loss of weight with BCT are modest at the end of the follow up period and that most of the studies report low adherence to treatment. It is recommended that public and private funds are needed to implement effective and safe multicentric long term randomized studies on different cultural populations, including most Latin-American countries.