Work package 3

led by Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), France

WP3: Dietary amino acid bioavailability/utilisation and the impact of physical activity on these parameters in older persons with poor appetite and at high risk of undernutrition. Comparison of an innovative plant protein-fibre product with whey protein

The objective of this work package was to understand, within the person, how the protein intake is distributed in the body according to whether these dietary proteins are of animal or vegetable origin. We already know that after digestion, amino acids from vegetable proteins are more retained in the organs of the abdomen, which requires more protein intake than for animal proteins. The consequence of this is a reduction in the supply of nutrients (amino acids), in particular for the muscle, and therefore an increased risk of loss of mobility and dependence. However, older adults often have a reduced appetite, which will make an increase in intake difficult to achieve in this population. 

We therefore looked at whether a physical activity program adapted to older adults can have a beneficial influence on the distribution of dietary amino acids of plant origin to the muscle and what the mechanisms would be (See image below). 

We worked with 12 older participants with small appetites, to test a meal composed solely of animal proteins (whey proteins) or vegetable proteins mimicking the amino acid intake of our "whey" meal. For both proteins sources, we measured the amount of amino acids that is retained in the organs of the abdomen and whether the meal is able to stimulate the anabolism of the muscle.  We repeated the same measures after 12 weeks of adapted physical training.

This work package investigated if a mixture of plant protein mimicking the amino acid intake of an animal protein is more or less well distributed effectively in the body and whether physical activity allows improving the anabolic effect whatever the chosen sources.