Índice glcémico e insulinemico de dos tipos de pasta de presentación larga y corta en individuos sanos / Glycemic and insulinemic index of two types pasta of short and long presentation in healthy subjects

AIM: To measure the glucose and insulin responses of a standard dry pasta and a dry pasta enriched with egg in their long and short presentation. MATERIAL AND METHODS: The glycemic index (GI) and the insulin index (II) were determined in a randomized, cross over protocol in 10 healthy volunteers between 26 and 58 years of age. Each subject underwent ten tests: six with the standard meal (bread) and four with the study pastas. Every study pasta was evaluated 10 times. Blood glucose and insulin levels were measured in the fasted state and over the 180 min following commencement of consumption of the foods. The Area Under the Curve (AUC) was calculated for the values above baseline for the 3-hour period following the meal. GI and II were calculated as the ratio of glucose and insulin Auks for a given test meal and the AUCs for the standard meal. RESULTS: Both type of pasta in their long and short presentation had lower GI than the standard meal (long pasta A: 47.8+/-54.4 percent, pasta B: 58.6+/-95.4 percent; short pasta A:71.4+/-32.8, pasta B: 79.9+/-47.6 percent percent p<.001). The II was lower with the two type of large pasta compare to the standard meal and to the two type of short pasta (p<.005). CONCLUSIONS: This study has shown that dry pasta with or without addition of egg put in the mass, is low Gl food. Long dry pasta has lower insulin response.

Introducción: Las pastas secas (industrializadas) se caracterizan por ser manufacturadas a base de harina dura de trigo y otros cereales, llamado semolina, a diferencia del pan que se prepara con harina fina, lo que supone que la respuesta insulinémica y glicémica debiera ser menor que la del pan. Objetivo: Medir la respuesta glicémica e insulinsulinémica de una pasta seca estándar y una pasta seca enriquecida con huevo, de presentación larga (espagueti) y corta (corbata). Material y Métodos: El índice glicémico (IG) e índice insulinémico (II) se determinaron en 10 sujetos sanos entre 26 y 58 años de edad. En forma aleatoria a cada sujeto se le midió la glicemia e insulina en ayuno y después de ingerir en forma isoglucídica alimento estándar (pan marraqueta) o los 2 tipos de pasta en presentación larga o corta a los 15,45,60,90,120,150 y 180 minutos. Posteriormente se calculó el área bajo la curva (ABC) de glucosa e insulina en cada sujeto. Los IG e II fueron calculados como la razón entre el ABC para un alimento de prueba dado y el ABC del alimento estándar (considerado el 100 por ciento). RESULTADOS : Ambos tipos de pasta en presentación larga y corta presentaron menor IG que el alimento estándar (marraqueta) ( pasta larga A: 47,8+/-54,4, pasta larga B: 58,6+/-95,4 por ciento; pasta corta A:71,4+/-32,8 por ciento, pasta corta B: 79,9+/-4,.6 por ciento p<001). El II de los dos tipos de pasta larga fue menor que el alimento estándar y los mismos tipos de pasta, pero cortas (p<.005). El II de las pastas cortas no se diferenció del alimento estándar. Conclusión: Este estudio demostró que las pastas secas con o sin adición de huevo tienen una menor respuesta glicémica que el alimento estándar, por lo tanto, se pueden clasificar como alimento de bajo IG. Además las pastas de presentación larga tienen una menor respuesta insulinémica.

La mantención de peso en humanos podría ser equivalente a la restricción calórica de los modelos animales? / Weight maintenance in humans. Could it mimic calorie restriction of animal models?

BACKGROUND: Energy restriction (ER) extends life span in animals, by decreasing oxidative stress. AIM: To compare adiposity, metabolic variables and DNA oxidative damage, among adults, reporting a constant body weight (weight maintainers), versus those reporting a progressive increase (weight gainers). SUBJECTS AND METHODS: Clinical history, dietary recall, anthropometric measures, abdominal CT scan and fasting blood samples (to measure lipoproteins, glucose and insulin), were obtained in 44 males. These subjects were classified as weight maintainers if they had a change in weight of 3 kg or less in the last 10 years, or weight gainers, if they had a weight increment of more than 6 kg, in the same lapse. Oxidative damage was assessed by 8-hydroxydeoxyguanosine (8-OHdG), in DNA extracted from circulating lymphocytes, in 5 weight maintainers, 8 weight gainers and 5 healthy elders. RESULTS: Energy Intake was 18% higher in weight gainers (p <0.01). Adiposity and central fat were higher among weight gainers (p <0.01). Abdominal fat correlated with serum lipoproteins, glucose and insulin sensitivity, assessed by the Homeostasis Model Assessment (HOMA). 8-OHdG levels did not differ between groups. CONCLUSIONS: The analysis of weight change based on the clinical history correlates with actual body composition, thus it may be a reliable indicator of long term energy Intake. This method could be comparable to weight clamp models employed in animals to study aging.

Características biológicas, familiares y metabólicas de la obesidad infantil y juvenil / Familial and metabolic characteristics of infantile and juvenile obesity

Background: Obesity is the most prevalent nutritional disease in people of less than 20 years old. Aim: To report biological, familial and metabolic characteristics in obese children. Patients and methods: A retrospective review of 187 children seen at obesity clinics and that had a complete metabolic study. Results: Ninety five prepuberal and 92 puberal children, aged 8.7ñ2.2 and 12.6ñ2.2 years old respectively, were studied. Body mass index was over 4 standard deviations in 48.4 per cent of prepuberal children and in 39.1 per cent of puberal children. Paternal obesity was twice more prevalent (30.2 per cent) than in the general population. The daily caloric intake and basal metabolic rate (BMR) were within the normal range; nevertheless there was a positive caloric balance due to minimal physical activity. The mean daily fat intake was normal (26.4ñ8.5 and 25.3ñ9.1 per cent of total calories in prepuberal and puberal children respectively). The daily fiber intake was under 70 per cent of recommendation. The total cholesterol was over 200 mg/dl in 26.6 and 23.9 per cent of prepuberal and puberal children. LDL cholesterol was over 130 mg/dl in 27.3 and 26.6 per cent and triacylglycerol was over 150 mg/dl in 16.9 and 25 per cent of prepuberal and puberal children respectively. Basal serum insulin was over 20 uIU/ml in 27.7 and 42.2 per cent of prepuberal and puberal children, respectively. Post glucose serum insulin was over 60 uIU/ml in 40 and 63 per cent of prepuberal and puberal children, respectively. Conclusions: Infantile and juvenile obesity is a chronic disease with a high incidence of metabolic alterations

Importancia de la leche en la nutrición del adulto mayor / Importance of milk in elderly nutrition

El proceso de envejecimiento es un fenómeno complejo que abarca cambios moleculares, celulares, fisiológicos y psicológicos. Los adultos mayores son especialmente susceptibles a presentar problemas nutricionales, tanto por alteraciones gastrointestinales, como por cambios en los requerimientos de nutrientes, alteraciones en la sensación del gusto, deterioro en la dentición, uso de medicamentos, depresión, aislamiento social y pobreza, siendo esta última la más importante causa de malnutrición en este grupo etáreo. En la mayor parte de la población el consumo de alimentos saludables se encuentra muy limitado, no alcanzando a cubrir los requerimientos de proteínas, minerales y micronutrientes. Una alimentación saludable, variada, con buen aporte proteico y de micronutrientes, manteniendo una adecuada actividad física es fundamental para tener una mejor calidad de vida. Dentro de una alimentación saludable, la leche cumple un papel fundamental por su aporte de proteínas y nutrientes esenciales, dentro de los cuales se destacan las vitaminas B1, B2 y minerales como calcio y fósforo

Control de calidad de la densitometría ósea: precisión reproductibilidad y aplicación clínica / Quality control of bone densitometry: accuracy, precision and clinical application

Dual energy x-ray absorptiometry (DEXA) is one of the most widely used methods for bone mineral density (BMD), total body mass (TBM), total body fat (TBF), percentage of total body ft (TBF) and total body fat-free mass (TBFFM) measurements. We investigated the in vitro and vivo accuracy and precision of DEXA in repeated measurements of a lumbar espine phantom and in 30 healthy volunteers. Based on precision, the minimal significant variability (MSV) at 95 por ciento confidence level between 2 measurement of the same object or subject was calculated. In vitro accuracy and MSV were 99.8 and 0.9 por ciento respectively. In vivo indexes were 99.4 and 0.9 percent for whole-body BMD. 98.6 and 2 percent for lumbar spine BMD, 96.6 and 4.8 percent for femoral neck BMD, 98 and 2.8 percent for major trochanter BMD, 96 and 5,7 percent for Ward's triangle BMD, 99.5 and 0.7 percent for TBM, 98 and 2.9 percent for TBF, 97.9 and 3 percent for TBF and 99 and 1.4 percent for TBFFM. Our fIndings indicate that DEXA is a very reliable instrument and in order to be 95 percent confident of a real change between 2 scans a difference of at least the calculated MSV must be measured

Análisis comparativo de métodos de evaluación de la composición corporal en varones adultos sanos / Comparative analysis of body composition assessment methods in healthy adult men

Background: The degree of agreement bbetween different methods to assess total body composition is not well known. Aim: To determine the level of agreement for total body fat mass measurement by dual-photon absorptiometry (DEXA), bioelectrical impedance (BIA) and anthropometry using the deuterium dilution method as the gold-standard technique, in normal male volunteers. Subjects and methods: Total body fat mass was measured by DEXA, BIA, anthropometry and deuterium dilution in thirty one healthy men, aged 41.9 ñ 8.6 years old. Results: Mean differences in percentage of total body fat compared with deuterium dilution were 0.3 percent ñ 2.2, 1.3 percent ñ 3.4 and 1.8 ñ 2.3 percent for DEXA had the lower difference with deuterium dilution and the confidence intervals for this difference (ñDS) showed that, at the individual leve, the maximum difference was 4.4 percent. Conclusions: All the methods evaluated gave similar average measurements for total body fat mass, but with different individual variability. In this group of healthy male subjects, DEXA was the best method in terms of agreement with the gold-standard

Actividad física en escolares chilenos normales y de talla baja / Physical activity in normal and low height for age chilean school children

En 70 niños y niñas escolares de 7 a 9 años de edad, normales y con talla baja (T/Eñ1 DE y <-1 DE), se evaluó la actividad física habitual mediante entrevistas estructuradas y por método factorial o de tiempo movimiento. La mayoría de las actividades de estos escolares eran sedentarias. El tiempo dedicado a horas de sueño o en cama, en días de la semana y festivos fue muy alto, los promedios (talla normal y baja) en los varones eran de 11,5ñ1,1 a 12ñ1,4 horas y en las niñas 11,9ñ1,2 y 12,2ñ1,6 respectivamente. El tiempo destinado a ver televisión era, en varones y niñas, promedio tres horas diarias, aumentando a cuatro horas en los días festivos. Los varones normales destinaron 58.6 por ciento de su tiempo a actividades físicas intensas, porcentaje significativamente mayor que sus pares de talla baja y los dos grupos de niñas (p<0,05). Un comportamiento similar se observó en las niñas normales frente a sus pares de talla baja, pero esta diferencia no alcanzó significación. Así pues, los escolares de talla baja se involucraron menos en actividades intensas que los normales, y que el tiempo destinado a ver televisión y la escasa actividad física desarrollada por estos niños, refleja un estilo de vida sedentario por parte de este grupo de edades

Métodos de estimación de la composición corporal de ancianos: análisis crítico / Body composition estimation methods in elderly: critical analysis

The objective of this study was to compare the values obtained for total body fat obtained with deuterium dilution, anthropometry and bioimpedance in 41 institutionalized elderly individuals (65-90 years old). The values obtained with each technique were compared using the graphic analysis proposed by Bland and Altman, that plots the difference between measurements with both methods against their average. In men (n=20) and women (n=21), the best degree of agreements was obtained between the values measured by deuterium dilution and those calculated from skinfolds (mean difference=1.4 percent and 6.9 percent respectively). The limits of agreement (ñ2SD) for skinfolds reached a maximun of 14.8 percent in men, and 16.8 percent in women. These values tend to underestimate fat in the obese and overestimate it in thinner subjects. For bioimpedance and deuterium dilution, the inter-method difference is significantly greater: 9.3 percent in men and 14.7 percent in women. This lack of agreement is attributed to the fact that the bioimpedance equipment utilizes equations validated for younger adults. In conclusion, estimation of body composition using skinfolds has the smallest difference compared with deuterium dilution, eventhougt individual measurements are not clinically acceptable. Caution is recommended when using individual measurements of body composition in the elderly, due to large errors in the determinations

Absorción de minerales de una nueva fórmula láctea propuesta para el Programa Nacional de Alimentación Complementaria / Mineral absortion in a new modified milk formula proposed to the complementary feeding national programme

La leche de vaca tiene un contenido excesivo de calcio y fósforo e insuficiencia de zinc y cobre. En la formulación de una leche modificada se han cambiado las concentraciones de estos minerales, para acercarlas a las recomendaciones normales. Se estudió la absorción de estos nutrientes en 9 lactantes hospitalizados en recuperación nutricional (x P/T: *85%). Cada niño recibió leche de vaca y leche modificada por 6 días, usándose los tres últimos días de cada período para balance. Encontramos ingestas inadecuadas de cobre (50%) y zinc (50%) y absorciones bajas de cobre (13 *g*kg*d), en relación a las correspondientes recomendaciones, cuando se empleó leche de vaca no modificada. Con la leche modificada sólo la ingesta de zinc (60%) fue insuficiente. Las ingestas de calcio (140%) y fósforo (117%) fueron excesivas mientras los niños recibían leche de vaca, pero adecuadas con leche modificada. La leche modificada empleada en este estudio asegura ingestas y absorciones más adecuadas que la leche de vaca no modificada para los minerales evaluados