Protein Malabsorption clinical trials

Bioavailability of Proteins From Plant Based Diets

The quality of protein intake has an important role within the nutritional needs of people throughout their lives around the world, particularly in developing countries and in particular during pregnancy and early childhood. It is likely that adequate protein reduce by 40% the prevalence of stunting (low height for age) in children under five years, according to World Health Organization data. Uncertainty about the quality of the diet, specifically with reference to quality proteins has potential impacts on health, economy, agriculture, and food security of a nation. The amino acid digestibility estimates based on stool analysis do not represent the amount of absorbed amino acid. Ideally, the bioavailable amino acid should be measured by methods that assess the difference between consumed and absorbed amino acids. However, the uptake of amino acids is not readily non-invasively measured in healthy humans. The use of vegetable protein intrinsically labeled by stable isotopes offers a solution to this problem. The deuterated water (2H2O), with relatively low cost, is suitable for labeling plant proteins such as those of beans. The labeled amino acids are present in the test meal ingested and incorporated into the blood, representing a single measure of bioavailability. This study aims to develop and apply a new methodology, using stable isotopes, to evaluate the bioavailability of bean protein, a very important food in the Brazilian diet, according to cooking procedures, through the use of deuterium. The project will be divided into two parts: a human nutrition and an agriculture part, the latter by planting/harvesting deuterium-labeled Phaseolus vulgaris L. After two weeks of blooming, deuterium water will be added to the bean crop, which will be subsequently dried. Chemical analysis and assessment of incorporation of deuterium in the beans will be done. Concurrent with the cultivation of beans, there will be a protein absorption test with 15 healthy volunteers for validation of the methods. For comparison purposes, milk protein labeled with deuterium and C13 will be used. The volunteers will consume the test meals. Blood, urine and saliva samples will be collected at baseline (before food ingestion), and in different times after the meal. In the next phase of this research, labeled beans produced by the agriculture experiment will be used to measure the protein absorption of volunteers of different groups (older persons, and stunting and non-stunting children). The samples will analyzed by isotope-ratio mass spectrometry. This methodology may promote a better understanding of the absorption of proteins and amino acids using less invasive methods in different age groups and clinical conditions. This work will have an important impact for the general population as well as for agriculture and health-related professionals.