Metabolic Availability of Metionine From Lentils in Adult Men

Overview

The research study is being done so we can determine the quality of the protein present in Canadian lentils. Amino acids are the building blocks of protein and protein quality is determined by the amount of amino acids present and by their bioavailability (their absorption and use by the body). Some amino acids are essential which means they must be obtained from the diet. If any one of the essential amino acids is missing in the diet, the body cannot make proteins that are used to repair tissue build bone, teeth, etc… Lentils as a food source contain low amounts of the essential amino acid methionine which makes its protein incomplete. The amino acids in lentils are also affected by cooking. Our objective is to determine the amount of methionine in lentils that the body can use. We will test lentils by studying them after cooking them in a stew, on their own and by combining the lentil stew with rice in a mixed meal to make a more complete protein. This research is being done in order to bridge the gap between knowledge of protein requirement and the amount of food needed to meet that requirement. Results from this study will be important for recommendations guiding food choices of lentils as a major protein source in the diet. Previously the quality of dietary protein for human consumption was studied in animals. This study is being done in humans because studies in animals are not directly applicable to humans. Excessive animal protein consumption is also linked to cardiovascular disease. Plant protein sources like lentils are important alternatives shown to "enhance ecosystem resilience, and improve human health.

If you agree to take part in this study, you will receive 3 different amounts of lentils which will contain different amounts of the essential amino acid methionine as well as 3 different amount of lentils complemented with rice. The lentils will be cooked in a stew served on its own or served with the rice. The quality of the protein in the lentils will be compared to the quality of a reference protein (egg protein) by giving you 4 reference diets containing amino acids make up like the amino acids in egg protein. The amount of lentils you receive will be provided in a random order. Breath samples will be collected after the 4th meal in 15 min intervals for 1 hour. Breath collection will resume again two and a half hours after the 5th meal every 15 minutes until 30 minutes after the last meal. A total of 52 breath samples will be collected during each of the 3rd study day.