Editorial: Postprandial physiology

Authors: FIAMONICI, JARLEI - Universidade De Sao Paulo; Newman, John; BRENNAN, LORRAINE - University College Dublin

Submitted to: Frontiers in Nutrition
Publication Type: Other
Publication Acceptance Date: 11/28/2022
Publication Date: 12/9/2022
Citation: Fiamonici, J., Newman, J.W., Brennan, L. 2022. Editorial: Postprandial physiology. Frontiers in Nutrition. 9. https://doi.org/10.3389/fnut.2022.1107480.
DOI: https://doi.org/10.3389/fnut.2022.1107480

Interpretive Summary:

Technical Abstract: There is growing interest in understanding responses to food and nutrient intake for the study of health and disease. This interest has been triggered in part by the involvement of physiological processes that take place following the ingestion of a meal in the etiology of chronic diseases and to recent findings that have brought new perspectives to postprandial metabolism (1). For instance, the causes, consequences, and physiological role of postprandial inflammation has gained much attention and may ultimately provide unique understanding of vascular and metabolic disease risks and progression (2–4). Similarly, since the discovery of bile acid (BA)-sensitive receptors over 20 years ago, several functions not fully understood have been attributed to these metabolites in addition to their long established role in the digestion of lipids (5). In general, probing the postprandial dynamics in metabolite concentrations may provide novel diagnostic opportunities. Similar to changes in glucose and insulin levels during an oral glucose tolerance test (OGTT), changes circulating levels of other metabolites following a meal can often reveal metabolic dysregulation or the effects of an intervention with greater sensitivity than the plasma concentration of such markers in the fasted state (6, 7). One of the biggest challenges to the study of postprandial metabolism is the large interindividual variability observed in the metabolic responses to food intake. Such variability is no surprise as numerous factors including gastric emptying, intestinal transit, food digestion, and nutrient absorption, as well as the secretion of signaling molecules in response to the meal and their effects in target tissues play along in the orchestrated events that define systemic responses to food intake. Despite the complexity associated with the high interindividual variability, understanding its causes will constitute a great advance toward the development of personalized nutrition. Matching the challenges associated with the study of postprandial metabolism, scientists can now count on tools such as metabolomics and genomics, that are evolving and readily available to numerous groups, enabling novel observations that often challenge concepts of physiology laid decades ago. To get an idea of the impact of these novel technologies, 7 out of 8 articles in Research Topic issue come from studies that employed such tools. From this issue, Weinisch et al. compared the metabolic responses of a group of young males to three different dietary challenges, using 600 metabolites profiled using metabolomic platforms. A core set of metabolites were identified as responding to all three challenges. The results indicate what are the hot targets if one is interested in assessing adaptations to the intake of macronutrients. From the same HuMet study, Fiamoncini, Rist et al. focused exclusively on the dynamics of plasma BA after different metabolic challenges that include an extended fasting and two postprandial tests. The study highlights the high interindividual variability of BA appearance in plasma as well as the large amplitude of this phenomenon. The biggest novelty of the report was the description of decreased BA levels in response to 36 h of fasting. Fiamoncini, Donado-Pestana et al. also contributed to this issue with an article based on data generated during the NutriTech study. Considering only glucose concentrations measured during an OGTT, two groups of individuals were identified amongst the study population with clearly different insulin sensitivity, even though all subjects were considered euglycemic according to WHO guidelines for fasting glucose levels. The study confirms previously published markers of insulin resistance/sensitivity and indicates the association of specific metabolites with better glycaemic responses