How the body handles sugar after meals in people who are lean or have obesity

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

Healthy adults, both lean and with obesity, will drink a small amount of 14C-labelled glucose and then eat meals with different glycaemic properties. Researchers will track how glucose is metabolized over a 12-hour lab day and over several days using blood, breath, urine, stool samples, indirect calorimetry, and advanced tracing to quantify the polyol pathway activity and overall glucose fate. The study uses a microtracer approach to measure glucose-derived carbon in various metabolic outputs, aiming to quantify differences between meal types and weight groups. The goal is to better understand how obesity and dietary glycaemic load influence glucose handling and related metabolic pathways.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* 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 Criteria:

* 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)
* HbA1c higher than 53 mmol/mol
* 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
* Any previous motor disorders or disorders in muscle and/or lipid metabolism
* Known severe kidney problems
* Presence of an ulcer in the stomach or gut and/or strong history of indigestion
* Recent or chronic history of diarrhoea
* Known anaemia
* A personal or family history of thrombosis (clots), epilepsy, seizures, or schizophrenia.
* 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)
* History of any drug or alcohol abuse in the past two years
* A confirmed positive alcohol breath test at screening or admission
* Drug use
* Claustrophobia
* Subjects who are on a weight loss diet or following a high calorific/high protein diet to gain weight
* Subjects with functional constipation
* 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
* Currently taking part in another scientific research
* Having received a product with 14C in the past 12 months
* Pregnant or breastfeeding
* 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.
* 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

Where it's running

• Wageningen University and Research
  Wageningen, Netherlands Recruiting

Study contacts

• Principal investigator: Marlou Dirks, PhD — Wageningen University
• Study coordinator: Marlou Dirks, PhD
• Email: Marlou.Dirks@wur.nl
• Phone: +31 317-484 136

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.