Effects of Different Whole Grain and Added Sugar Diets on Health in Adults Aged 21 to 60

What this Trial Is About

Researchers are evaluating the effects of eating different types of grain foods with varying whole grain and added sugar content in adults aged 21 to 60 years. This 16-week randomized controlled trial aims to understand how diets with whole grain versus refined grain and different sugar levels impact taste preferences, appetite, energy intake, body weight, blood pressure, blood sugar levels, and blood fats. The study will also explore how these diets affect gut microbiome composition and function while controlling for added sugars, saturated fats, and sodium. Participants will be randomly assigned to one of four diet groups, each differing in whole grain servings and added sugar levels high whole grain with low sugar, low whole grain with low sugar, high whole grain with high sugar, and low whole grain with high sugar. All diets will have about 50% carbohydrate, 35% fat, and 15% protein energy content, with grain foods making up half of the carbohydrate portion. The diets will be followed over the 16 weeks, with specific servings of grain foods prescribed according to the assigned group. Throughout the study, participants will undergo various assessments including fasting blood tests, meal tolerance tests, body weight and composition measurements, continuous glucose monitoring, dietary intake tracking, taste preference testing, appetite ratings, physical activity monitoring, blood pressure measurements, and microbiota analysis. These evaluations will occur at baseline and several time points during the 16 weeks to monitor changes. Compliance with the diet will also be tracked to ensure adherence. The primary outcome is blood sugar control at 12 weeks, with multiple secondary outcomes related to appetite, taste, energy intake, body weight, blood pressure, and blood fats.

Health Effects of Grain Foods in Adults