GutSelf: Interindividual Variability in the Processing of Dietary Compounds by the Human Gastrointestinal Tract

Abstract

Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods.

Keywords: digestion; food; gastrointestinal tract; gut microbiome; polymorphism.

Figure 1

Overview of molecular variables contributing to inter‐individual variability in the processing of fat by the GIT.

Figure 2

Postprandial kinetics of the lactose‐derived metabolites galactonate (left) and galactitol (right) in the serum of subjects having ingested acidified milk. The relative intensities of galactonate and galactitol were measured by GC–MS. The red lines represent subjects with the CC genotype at the MCM6 rs49882359 allele. The orange lines represent subjects with the CT genotype. The green lines represent subjects with the TT genotype. Adapted from Vionnet et al.

Figure 3

Overview of polymorphisms involved in mineral absorption by the GI tract.