Effects of Omeprazole Ingestion on Postprandial Amino Acid Concentrations in Response to a Mixed Meal
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age50-60
SponsorMcGill University
About this trial
Omeprazole is a proton pump inhibitor commonly used to reduce stomach acid in the treatment of heartburn, gastroesophageal reflux disease, and gastric ulcers. By blocking the H⁺/K⁺-ATPase pumps in the gastric lining, it raises gastric pH and can alter the normal activation of pepsin, the enzyme responsible for beginning protein breakdown in the stomach.
Under normal conditions, dietary proteins are denatured by gastric acid and cleaved by pepsin into smaller peptides. These peptides enter the small intestine, where pancreatic enzymes (trypsin, chymotrypsin) and brush-border peptidases (aminopeptidase, dipeptidase) further hydrolyze them into free amino acids that are absorbed into the bloodstream. Suppressing stomach acidity may allow larger peptides to pass into the intestine, potentially reducing the efficiency of amino acid liberation and absorption.
In this randomized, crossover study, adults aged 50-60 years will attend two study visits at least one week apart. In one visit they will take a standard dose of omeprazole before consuming a mixed meal with a fixed protein content; in the other visit they will consume the same meal without medication. Blood samples will be collected before the meal and at multiple time points afterward to measure plasma amino acid concentrations and compare postprandial responses.
Older adults experience anabolic resistance, meaning they require higher protein intakes to stimulate muscle protein synthesis effectively. If omeprazole reduces amino acid availability after a meal, individuals taking this medication may need adjusted dietary protein recommendations. Findings from this study will help refine nutrition guidelines for people on proton pump inhibitors and support optimal muscle health and recovery in middle-aged and older adults.
Eligibility criteria
This trial accepts healthy volunteersQualifiers
Healthy adult female or male participants who are 50 to 60 years of age at screening (inclusive)
Has a BMI between 18.5 to 29.9 kg·m-2 (inclusive) at screening visit
In good general health (no uncontrolled diseases or conditions) as deemed by the investigator and able to consume the study product
Has maintained stable use of medication and supplements stable dietary and lifestyle habits, and stable body weight, for the last 3 months prior to screening and agree to maintain them throughout the study
Disqualifiers
Individuals who are lactating, pregnant or planning to become pregnant during the study
Individuals who adhere to a diet (e.g., vegan diet) that restricts consumption of dairy products
Has a known sensitivity, intolerability, or allergy to any of the study products or their excipients (i.e., lactose intolerant)
Weight loss or gain > 3 kg in the 3 months prior to study visit 1
Trial design
Design model
Crossover
Treatments tested in this trial
Omeprazole 20 mg
DrugOmeprazole 20mg capsule 1 dose = 1 capsule Participants will consume one dose per day for 5 days prior to their study visit. They will also consume one dose the day of the study visit in the laboratory setting. They will also consume one dose with the standardized mixed meal containing chicken, peas, potatoes, and butter the day of the study treatment visit in the laboratory.
Placebo
Other interventionPlacebo 1 dose of placebo = 1 capsule filled with maltodextrin Participants will consume 1 dose per day for 5 days prior to their study visit. They will then consume 1 dose the day of their study visit in the laboratory setting. They will also consume one dose with the standardized mixed meal containing chicken, peas, potatoes, and butter the day of the study treatment visit in the laboratory.
Treatment groups
4 Participants
are divided into 2 treatment groupsGroup A: Omeprazole 20mg capsuleActive comparator 1 intervention
Group B: PlaceboPlacebo comparator 1 intervention
Trial outcomes
Primary outcomes
1
Incremental Area Under the Curve for Total Plasma Amino Acid Concentrations
Plasma total amino acid concentrations (µmol·L-¹) measured by LC-MS at each time point; iAUC calculated using the trapezoidal rule to quantify the postprandial rise in amino acids after a single mixed meal in the Omeprazole versus placebo condition.
Time frame
0-300 minutes post-meal (blood draws at baseline (0), 30, 60, 90, 120, 180, 240, and 300 minutes)Secondary outcomes
1
Total (0-5 hours) postprandial plasma branched chain amino acid concentration incremental area-under-the-curve
Free leucine, isoleucine, valine (combined) (µmol·L\^(-1)·300 minutes)
Time frame
5 hours2
Total (0-5 hours) postprandial plasma leucine concentration incremental area-under-the-curve
Free leucine (µmol·L\^(-1)·300 minutes)
Time frame
5 hours3
Postprandial plasma amino acid maximum concentration
Total amino acids, essential amino acids, branched chain amino acids, leucine (µmol/L)
Time frame
5 hours4
Postprandial plasma amino acid time to peak concentration
Total amino acids, essential amino acids, branched chain amino acids, leucine (minutes)
Time frame
5 hoursSponsors and contacts
Click on the lead sponsor to view all of their trials.
McGill University
Lead sponsor
BIO-CAT, Inc.
Collaborator
Source ClinicalTrials.gov