How a vegetarian diet affects digestion of pea protein in young and older adults
Effect of a Vegetarian Diet on the Bioavailability of Amino Acids From Plant Protein in Healthy Young and Elderly Volunteers (VEGAA)
We will test whether pea protein is broken down and used differently by young and older adults who follow vegetarian or omnivorous diets.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 48 (estimated) |
| Ages | 18 Years to 75 Years |
| Sex | All |
| Sponsor | Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement Academic / other |
| Locations | 1 site (Bobigny) |
| Trial ID | NCT07521189 on ClinicalTrials.gov |
What this trial studies
The trial compares pea protein digestion and metabolic use in four groups: young omnivores, young vegetarians, older omnivores, and older vegetarians, with four groups of 8 volunteers each. Peas are labeled with safe stable isotopes (15N and 2H) and participants attend two clinical investigation days separated by 4 weeks to 2 months. On the first day a 15N-labeled pea meal is consumed and blood is sampled over 8 hours with urine collections to measure postprandial nitrogen and protein metabolism, and on the second day amino acid digestibility of the pea protein is evaluated. Results will show how age and habitual diet influence plant protein bioavailability.
Who should consider this trial
Good fit: Healthy adults aged 18–23 or 65–75 with BMI 18–30 who consistently follow either a vegetarian (no meat or fish, >70% protein from plants) or omnivorous diet (>70% protein from animal sources, meat >3 times/week) and meet lab and consent requirements are ideal candidates.
Not a fit: People with food allergies, anemia, positive viral serologies, pregnant women, those under legal protection, or anyone outside the specified age or dietary groups would not be eligible and are unlikely to benefit from participating.
Why it matters
Potential benefit: If successful, the results could help tailor protein recommendations and food choices for older adults who rely on plant-based proteins.
How similar studies have performed: Previous work shows plant proteins are generally less digestible than animal proteins, but direct isotope-labeled comparisons across age and habitual diet groups are limited, making this approach relatively novel.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Normal weight or overweight (18 \< BMI \< 30 kg·m-²) * Male or female * Aged 18-23 years (young groups) or 65-75 years (older groups) * Following an omnivorous diet (regular consumption of meat products, with meat intake \> 3 times/week and \> 70% of protein intake from animal sources) or vegetarian diet (exclusion of meat and fish/seafood, with \> 70% of protein intake from plant sources) * In good general health (WHO = 0) * Affiliated with a social security system * Free and informed consent, provided in writing after receiving the information required by the Public Health Code Exclusion Criteria: * Adults under legal protection or unable to give informed consent (e.g., under guardianship, trusteeship, or legal protection) * Any known food allergy * Positive serology for HBsAg, anti-HBc, HCV, or HIV * Anemia: hemoglobin level \< 13 g/dL in men and \< 12 g/dL in women * Pregnant women or those who may be pregnant (based on a positive urine pregnancy test at inclusion) * Excessive alcohol consumption (\> 2 drinks/day). Harmful alcohol use will be assessed by the investigator at inclusion. * Hypertension, diabetes, gastrointestinal, liver or kidney diseases, or severe heart disease. These conditions will be assessed by the investigator based on standard clinical evaluation and participants' self-reports at inclusion. * Hypertension: significant arterial hypertension according to the investigator, or systolic blood pressure ≥ 140 mmHg and/or diastolic blood pressure ≥ 90 mmHg at inclusion. * Diabetes: type 1 or type 2 diabetes, or fasting blood glucose \> 1.25 g/L. * Gastrointestinal disease: clinically significant gastrointestinal disorders (bleeding, vomiting, constipation/diarrhea grade \> 1) as judged by the investigator, any inflammatory bowel disease, or acute gastroenteritis in the month prior to the intervention. * Liver disease: any significant hepatic disorder according to the investigator, or ASAT/ALAT \> 2.5 times the upper normal limit. * High-level athletes (\> 8 hours of training per week) * Blood donation within 8 weeks prior to study start * Absence of free, informed, written consent after receiving the information required by the Public Health Code * Not affiliated with a social security system
Where this trial is running
Bobigny
- Centre de Recherche sur Volontaire, Hopital Avicenne (AP-HP) — Bobigny, France (Recruiting)
Study contacts
- Study coordinator: Juliane Calvez, PhD
- Email: juliane.calvez@agroparistech.fr
- Phone: +33189100875
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.