Study of How Vegetarian and Omnivorous Diets Affect Pea Protein Use in Healthy Young and Older Adults

What this Trial Is About

Researchers are investigating how plant proteins, especially pea proteins, are digested and used in the body by young and older adults who follow vegetarian or omnivorous diets. The study focuses on understanding protein digestion and metabolism differences between these groups, which is important as plant proteins typically have lower digestibility than animal proteins. This research aims to provide insights into how aging might affect the availability of plant proteins, which is valuable for nutritional strategies targeting populations with higher protein needs, such as the elderly. Volunteers are divided into four groups based on age and diet young vegetarians, young omnivores, older vegetarians, and older omnivores. Each participant attends two clinical investigation days separated by 4 weeks to 2 months. On the first day, they consume a pea-based meal labeled with a safe isotope 15N, and nitrogen retention and protein metabolism are measured through blood and urine samples over 8 hours. On the second day, participants eat portions of a pea-based meal labeled with another isotope 2H every 30 minutes for 7.5 hours, combined with labeled amino acids 13C. Blood, breath, and respiratory samples are collected to evaluate amino acid digestibility and metabolism. Throughout the study, researchers collect blood samples, urine, breath, and measure respiratory exchanges to assess amino acid bioavailability, protein metabolism markers, and gut hormones. Participants diets are characterized via an online questionnaire. The primary outcome is pea amino acid bioavailability measured over 8 hours on the second investigation day. Secondary outcomes include protein desamination and plasma kinetics of pea protein measured on the first day. The total participation spans two clinical visits separated by several weeks, ensuring detailed metabolic assessment under controlled conditions.

Effect of Vegetarien Diet on Protein Digestibility in Young and Elderly Volunteers