Quantifying differences in bioavailability of different dietary proteins in older adults

Quantifying differences in bioavailability of different dietary proteins in older adults






Landbouw, Water, Voedsel>D. Gewaardeerd, gezond en veilig voedsel>D2. De consument, duurzame en gezonde voeding in een groene leefomgeving






To enable sustainable utilization of dietary protein and support Priority 26 / MMIP D2, this project will assess digestibility and metabolic availability of proteins in older and young adults in vivo and in vitro. Valorisation of the outcomes via product development, communication and education will provide clear opportunities to ensure that dietary protein requirements can be sustainably fulfilled for older adults in our population that are at risk of malnutrition.

Doel van het project

This project coontributes to Priority 26 MMIP D2 (De consument, duurzame & gezonde voeding, in een groene leefomgeving) because implementation of healthy choices of food and nutrition, which this Priority targets, requires close matching between nutritional requirements for specific subpopulations and how they can be supplied via food products. The key role of protein in the diet highlights the importance of matching protein quantity and quality to nutritional requirements. Insufficient protein or poor-quality protein will not help people meeting their requirements, whereas oversupply leads to increased environmental load, both from a primary production perspective as well as from an environmental load of human excretions. Moreover, overconsumption may also lead to excess energy intake, which contributes to obesity. Hence, enabling healthy choices for protein sources in a sustainable diet requires matching supply to needs and requirements for subpopulations. Providing protein through the diet is thus not simply a matter of meeting general protein intake recommendations, but also a matter of providing the right proteins in sufficient amounts to meet nutritional requirements for a specific subgroup of the population. Current protein recommendation and protein quality evaluation systems are typically representative for the general population of healthy young adults. However, it is known that the human body’s ability to digest proteins and absorb and utilize dietary amino acids is affected by attributes such as age and disease. Therefore, protein requirements for healthy young adults will not adequately reflect those of other, often more vulnerable, groups. One key example of this is the large group of older adults in our society. Almost 50% of people in this group are at moderate or high risk for protein-energy malnutrition, a condition that is associated with delayed recovery of disease, poorer quality of life and increased risk of morbidity and mortality. In this project, we aim to quantify differences in bioavailability, determined as digestibility and metabolic availability, of different dietary proteins in young and older adults. This projects complements other ongoing projects which all largely focus on protein quantity and appear to overlook the paramount importance of protein quality or matching to nutritional requirements according to the specific age group. Likewise, when considering most models for healthy and sustainable diets, these are also primarily focussed on protein quantity rather than protein quality. This leads to the risk of either not meeting nutritional requirements or oversupplying protein, with associated environmental risks. The current project aims to fill this gap in the portfolio and thereby make an important contribution to the adequate selection of protein in a sustainable diet and the overall aims of Priority 26 MMIP D2 (De consument, duurzame & gezonde voeding, in een groene leefomgeving). In addition, the project also contributes to key technology ST1 (Smart Technologies in Agri-Hort-Water-Food), which aims to develop non-invasive measurement techniques for humans. By determination of protein quality with stable isotope techniques in vivo, as we aim to do in this work, non- or minimally-invasive techniques can be applied. Furthermore, exploration of in vitro digestion at conditions relevant for older adults will further reduce the need for human trials.

Relatie met missie (Motivatie)

The central role of proteins in the striving towards a healthy and sustainable diet places protein intake at the forefront for achieving the targets for Priority 26 and MMIP D2 “De consument, duurzame & gezonde voeding, in een groene leefomgeving”. This entails not only consuming sufficient amounts of protein (protein quantity), but consuming sufficient amounts of those protein sources that can meet the nutritional demands for all groups of our society (protein quality). With the required sustainable production and use of protein, special attention should be paid to the nutritive value of dietary protein sources, particularly for groups in our society that are at risk of protein malnutrition. To do this sustainably, excessive intake of protein that is poorly utilised should also be prevented. In our research, we will conduct in vivo investigations into how protein digestibility and metabolic availability from various protein sources differs between older and younger adults using two -minimally invasive- stable isotope-based methods. Because the selected proteins sources (milk, sorghum and black bean) have previously been characterized using the DIAAS methodology, correlations can be established based on digestibility of the same protein sources in different target populations and by different methods. Based hereon, it is envisaged that the outcomes of this work can be extended beyond the protein sources studied and be applied also to other protein sources for which DIAAS is available. In addition, in vitro studies will also be included with the aim of developing valuable screening methods for protein sources not yet characterized for DIAAS, especially in older adults. With the outcomes of the work, industrial partners in the food sector will have optimal utilization of available information in the selection of the optimal quantity and source of protein in their products to target this specific subgroup. The optimal formulation of products enables older adults to meet their nutritional requirements sustainably by preventing excess consumption.

Naam projectleider

Thom Huppertz