Primary Prevention of Weight Gain for Women Aged 25-45

描述（由申请人提供） 这项研究将主要在巴西进行，作为NIH的延伸 赠款号R 01 CA 50385和R 01 HL 60712 - 01。 超重（BMI（身体质量指数）25.0-29.9）和肥胖（BMI大于或 相当于30公斤/平方米）现在影响超过40%的巴西成年人。妇女 处于生育年龄的女性尤其容易患肥胖症， 在过去二十年中，巴西的流行率有所上升。 增加脂肪摄入似乎不能解释这一趋势，而稳定的 全国豆类消费量下降。许多 研究表明，由于摄入了 特定的碳水化合物食物，通过血糖指数（GI）测量。一个 特别低的血糖反应与豆类有关， 低GI饮食可以：1）减少饥饿感; 增加饱腹感; 2）减少脂肪生成。在一项非随机随访中， 参加肥胖治疗计划的儿童，被分配到低 GI饮食组的BMI下降幅度大于高GI饮食组。没有长 长期临床试验的体重减轻或预防体重增加相比，低 高GI饮食然而，通过因素确定的饮食模式 巴西里约热内卢市的一项调查分析， 主要是米饭和豆类的摄入量与较低的肥胖风险有关。的 这项研究的目的是比较巴西妇女的有效性， 鼓励他们吃两种不同的饮食模式（低与高GI）， 相同的常量营养素组成，在18个月的过程中控制体重 个月低GI饮食模式将在很大程度上基于传统的 米饭和豆子的组合。对照组将被鼓励吃一个 大量营养素含量相同的饮食，但更接近西方饮食。两 饮食是巴西人消费的食物的现实处方。具体来说， 这项研究将比较体重（主要结果）、食物摄入、血液 206名育龄成年妇女的化学物质和饥饿/饱足情况， BMI为23-27 kg/m2，在4周导入期后随机分配至任一种饮食 期间吃高GI饮食。

DESCRIPTION (provided by applicant) This research will be conducted primarily in Brazil as an extension of NIH grants # R0l CA 50385 and R0l HL60712-0l. Overweight (BMI (Body Mass Index) 25.0-29.9) and obesity (BMI greater than or equal to 30 kg/m2) now affect more than 40 percent of adult Brazilians. Women at reproductive age are particularly at risk of obesity and a 70 percent increase in the prevalence was observed in the last two decades in Brazil. Increasing fat intake does not appear to explain this trend, whereas a steady decline in the consumption of beans has been shown for the whole country. Many studies have demonstrated changes in blood glucose levels due to the intake of specific carbohydrate foods, as measured by glycemic index (GI). An exceptionally low blood glucose response was associated with beans and it has been suggested that the consumption of low-GI diets may: 1) decrease hunger/ increase satiation; 2) reduce lipogenesis. In a nonrandomized follow-up of children attending a program of obesity treatment, children assigned to a low GI diet had a decrease in BMI greater than the high GI group. There are no long term clinical trials of weight loss or prevention of weight gain comparing low with high GI diets. However, a dietary pattern identified through factor analysis in a survey in the city of Rio de Janeiro, Brazil, that represents mainly rice and bean intake was associated with lower risk of obesity. The purpose of this study is to compare in Brazilian women the effectiveness of encouraging them to eat two different dietary patterns (low vs. high GI), with equal macronutrient composition, on weight control over the course of 18 months. The low GI dietary pattern will be heavily based on the traditional rice and beans combination. The comparison group will be encouraged to eat a diet with the same amount of macronutrients, but closer to a Western diet. Both diets are realistic prescriptions of foods consumed by Brazilians.Specifically, this study will compare changes in weight (main outcome), food intake, blood chemistries and hunger/satiation in 206 adult women at reproductive age, with BMI of 23-27 kg/m2, randomized to either one of the diets after 4-week run-in period eating a high GI diet.