Fructose Intestinal Gluconeogenesis

This study investigates whether the small intestine plays a protective role when people consume fructose (a sugar found in fruit and many processed foods) by converting it to glucose before it reaches the liver, and whether this protective mechanism is impaired in people with obesity. Participants undergo a specialized metabolic test in which they consume meals with different levels of fructose while receiving stable isotope tracers to track how the body processes the sugar. Eligible participants are either lean adults (BMI 19–25) or obese adults (BMI 30–38) who do not have diabetes, liver disease, or certain metabolic conditions. The study involves four outpatient visits approximately 3 weeks apart, each including an overnight fast, a 6-hour fed metabolic study, and frequent blood and urine sample collections. This summary was prepared to help patients understand the study in plain language.