How the body processes sugar after a meal in lean and obese adults

Trial details

Who runs it

Wageningen University

Trial code

NCT07690176

Record updated

8 July 2026

Original description

The goal of this clinical trial is to learn how a high-glycaemic meal affects the way the body processes glucose in healthy adults who are either lean or have obesity. The main questions it aims to answer are: Is the polyol pathway (conversion of glucose into sorbitol and fructose) more active after a hyperglycaemic meal? Is this pathway more active in individuals with obesity compared with lean individuals? We will compare people who eat a high-glycaemic meal with those who eat a low-glycaemic meal to see whether meal type changes how glucose is metabolized in the body. Participants will drink a small amount of 14C-labelled glucose so researchers can trace how the body uses glucose, spend one long study day (about 12 hours in the lab) plus short morning visits on days 2 to 4, and undergo repeated measurements, including blood sampling, breath sampling, indirect calorimetry, and complete urine and stool collection for 72 hours. This information will help us understand how glucose is processed in the body and whether people with obesity handle glucose differently than lean individuals.Read full original descriptionShow less

The Metabolic Effects of a Hyperglycaemic Meal in Lean and Obese Individuals Using a [14C]-Glucose Microtracer Approach

The goal of this clinical trial is to learn how a high-glycaemic meal affects the way the body processes glucose in healthy adults who are either lean or have obesity. The main questions it aims to answer are: Is the polyol pathway (conversion of glucose into sorbitol and fructose) more active after a hyperglycaemic meal? Is this pathway more active in individuals with obesity compared with lean individuals? We will compare people who eat a high-glycaemic meal with those who eat a low-glycaemic meal to see whether meal type changes how glucose is metabolized in the body. Participants will drink a small amount of 14C-labelled glucose so researchers can trace how the body uses glucose, spend one long study day (about 12 hours in the lab) plus short morning visits on days 2 to 4, and undergo repeated measurements, including blood sampling, breath sampling, indirect calorimetry, and complete urine and stool collection for 72 hours. This information will help us understand how glucose is processed in the body and whether people with obesity handle glucose differently than lean individuals.

Inclusion: Healthy males and females using contraception during and for 3 months after the study; Aged from 18-65 years at the time of signing informed consent; 18.5 < BMI < 25 kg·m2 or 30< BMI <35 kg·m2; Must be willing and able to communicate and participate in the whole study, including consumption of 14C-glucose and meals offered during study conduct; Must have regular bowel movements (i.e. average stool production of ≥1 and ≤3 stools per day); Must usually eat 3 meals per day (i.e. breakfast, lunch and dinner).

Exclusion: Any previous motor disorders or disorders in muscle and/or lipid metabolism; Drug use; Currently taking part in another scientific research; Having received a product with 14C in the past 12 months; Smoking or having used nicotine-containing products in the 6 months prior to the study; Subjects who have taken antibiotics within the 60 days prior to the adaptation period; Diabetes (Type 1, Type 2, or genetic form of diabetes); Any diagnosed cardiovascular (heart) disease or high blood pressure (≥140 mmHg systolic and/or ≥90 mmHg diastolic); History of clinically significant cardiovascular, renal, hepatic, chronic respiratory or gastro-intestinal disease, immunodeficiency, endocrine, neurological, or psychiatric disorders; Any diagnosed respiratory disease, such as COPD or asthma; Presence of an ulcer in the stomach or gut and/or strong history of indigestion; Recent or chronic history of diarrhoea; A personal or family history of thrombosis (clots), epilepsy, seizures, or schizophrenia; History of any drug or alcohol abuse in the past two years; Any known food allergies or intolerances to the 14 major food allergens (celery, cereals containing gluten, crustaceans, eggs, fish, lupin, milk, molluscs, mustard, tree nuts, peanuts, sesame seeds, soybeans, sulphur dioxide and sulphites) or history of a malabsorption syndrome including coeliac disease; Subjects who have regular gastrointestinal complaints including abdominal pain, stomach upsets and borborygmi or known or suspected irritable bowel syndrome; HbA1c higher than 53 mmol/mol; Known severe kidney problems; Known anaemia; Regular use of dietary supplements (>3 times per week); Chronic use of any prescribed or over the counter pharmaceuticals (excluding oral contraceptives and contraceptive devices); A confirmed positive alcohol breath test at screening or admission; Claustrophobia; Subjects who are on a weight loss diet or following a high calorific/high protein diet to gain weight; Subjects with functional constipation; Pregnant or breastfeeding; Currently involved in a structured progressive resistance training programme (>3 times per week); Sedentary lifestyle as assessed using the International Physical Activity Questionnaire [IPAQ]; Unable to give consent; Employed or undertaking a thesis or internship at the department of Human and Animal Physiology.

ClinicalTrials.gov NCT07690176