Does the gut convert fructose into glucose to protect the liver?

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

This crossover study will enroll lean and obese but otherwise healthy adults to compare how the small intestine handles fructose. After a baseline sugar tolerance test, participants will complete four outpatient tracer/feeding visits approximately three weeks apart, consuming liquid meals that differ only in fructose content while receiving oral or intravenous 13C-labeled fructose. During each six-hour fed tracer protocol, blood and urine samples will be collected frequently and vital signs and anthropometrics will be measured. Comparing high- and low-fructose meals and oral versus IV tracers will allow quantification of intestinal gluconeogenesis and whether that protective mechanism is impaired in obesity.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* BMI 30 to 38 kg/m2 (obese group) or BMI 19 to 25 kg/m2 (lean group)

Exclusion Criteria:

* Pregnancy or lactation within the past six months;
* Type 1 or 2 diabetes mellitus (including fasting glucose ≥126 mg/dL, HgbA1c ≥6.5%);
* History of liver disease or AST and ALT 2x above the upper limit of normal;
* Fasting triglyceride \> 300 mg/dl; total cholesterol levels above the 95th percentile for age and sex;
* Hemoglobin (Hgb) \<12.5g/d or hematocrit\<3x Hgb value;
* Report of HIV or hepatitis B or C infection;
* History of cancer, other than basal cell or squamous cell carcinoma or kidney disease stage 3 or higher or patients currently on dialysis;
* Use of any anti-diabetic medications or hypolipidemic agents in the past six months;
* History of surgical procedure for obesity;
* Change in body weight \>5% in the past six months (by self-report);
* History of other conditions known to affect insulin sensitivity and lipid metabolism (e.g., polycystic ovary syndrome), history of galactosemia, hereditary fructose intolerance, or who test positive for fructose malabsorption at screening;
* Known intolerance to acetaminophen.

Where it's running

• Touro University California
  Vallejo, California, United States Recruiting

Study contacts

• Principal investigator: Jean-Marc Schwarz, PhD — Touro University, California
• Study coordinator: Sally Chiu, PhD
• Email: schiu2@touro.edu
• Phone: 707-638-5404

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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.