Fat Absorption and Metabolism After Roux-en-Y Gastric Bypass

Status

Completed

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT04859816

Acronym

FAT-BAR

Enrollment

Registered

2021-04-26

Start date

2021-04-01

Completion date

2022-05-01

Last updated

2022-08-23

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Bariatric Surgery

Keywords

fat, triglyceride, triacylglycerol, Roux-en-Y gastric bypass, malabsorption

Brief summary

Using intravenous and oral administration of stable isotope tracers, we will investigate the importance of altered fat absorption and altered whole body fat metabolism for the reduced postprandial systemic TAG concentrations in non-diabetic patients in weight stable phase after RYGB.

Interventions

OTHERFeces collection

4-day feces collection

OTHERMetabolic test

Iv and oral administration of stable isotope tracers during fasting and a high-fat liquid mixed meal

OTHERDXA-scan

Dual energy X-ray Absorptiometry scan of whole-body fat

OTHERMRS

Magnetic resonance spectroscopy of liver fat content

Study design

Allocation

NON_RANDOMIZED

Intervention model

PARALLEL

Primary purpose

BASIC_SCIENCE

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to 75 Years

Healthy volunteers

Yes

Inclusion criteria

, RYGB * Age \> 18 years * RYGB \> 12 months prior to inclusion * Weight stable (± 3 kg during the last month) * HbA1c \< 48 mmol/mol before surgery, and no history of diabetes * HbA1c \< 48 mmol/mol and fasting plasma glucose \< 6.1 mmol/l at inclusion Inclusion criteria, CON * Age \> 18 years * No former bariatric surgery * Weight stable (± 3 kg during the last month) * HbA1c \< 48 mmol/mol, fasting plasma glucose \< 6.1, and no history of diabetes

Exclusion criteria

* Thyrotoxicosis or inadequately treated hypothyreosis * Haemoglobin \< 6.5 mmol/l at inclusion * Pregnancy (pregnancy test in fertile woman before enrolment) or breast feeding * Medication affecting the planned examinations which cannot be paused during the study period. * Adherence to extreme diets with excessively high or low contributions from certain macronutrients (e.g. ketogenic diet) * Complications restricting eating behavior (e.g. postprandial hypoglycemia, vomiting or strictures) * MR contraindications

Design outcomes

Primary

Measure	Time frame	Description
Area under the curve of plasma triacylglycerol	6 hours	During a high-fat liquid mixed meal test

Secondary

Measure	Time frame	Description
Recovery of oral stable triacylglycerol isotope tracer in feces	4 days	An oral stable triacylglycerol isotope tracer will be administered during a high-fat liquid mixed meal test. Feces will be collected the following 4 days to determine the recovery of the tracer in feces.

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026