Dietary intake of monosaccharides from foods is associated with characteristics of the gut microbiota and gastrointestinal inflammation in healthy US adults

Authors: Larke, Jules; BACALZO, NIKITA - University Of California, Davis; CASTILLO, JUAN - University Of California, Davis; COUTURE, GARRET - University Of California, Davis; CHEN, Y - University Of California, Davis; XUE, ZHENGYAO - University Of California, Davis; Alkan, Zeynep; Kable, Mary; LEBRILLA, CARLITO - University Of California, Davis; Stephensen, Charles; Lemay, Danielle

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/14/2022
Publication Date: 12/26/2022
Citation: Larke, J.A., Bacalzo, N., Castillo, J.J., Couture, G., Chen, Y., Xue, Z., Alkan, Z., Kable, M.E., Lebrilla, C.B., Stephensen, C.B., Lemay, D.G. 2022. Dietary intake of monosaccharides from foods is associated with characteristics of the gut microbiota and gastrointestinal inflammation in healthy US adults. Journal of Nutrition. 153(1):106-119. https://doi.org/10.1016/j.tjnut.2022.12.008.
DOI: https://doi.org/10.1016/j.tjnut.2022.12.008

Interpretive Summary: In effort to better understand how diet feeds our gut microbes, we must first dissect the glycans in our diet that feed them. In this study, we mapped dietary data of a healthy human cohort to a database of glycans in food (Davis Food Glycopedia) to determine the level of individual sugar monomers, or monosaccharides, in the diets of healthy adults living in the U.S. We found that, on average, dietary carbohydrates were comprised of mostly glucose (83.4%) followed by fructose (5.9%), galactose (4.7%), arabinose (2.1%) xylose (1.3%), GalA (1.2%) and mannose (0.8%). Seven additional monosaccharides were present at less than 0.5% on average. Increasing the diversity of monosaccharides consumed was associated with a healthier eating pattern which may be attributed to reduced intake of simple sugars. Furthermore, higher diversity of monosaccharide intake was associated with greater diversity in the gut microbiome and lower gastrointestinal inflammation. This is the first study to investigate dietary intake at this resolution of carbohydrate intake, a scale which can provide new insights on the relationship between diet and the gut microbiome and gastrointestinal health.

Technical Abstract: Background: Current assessment of dietary carbohydrates does not adequately reflect the nutritional properties and effects on gut microbial structure and function. Deeper characterization of food carbohydrate composition can serve to strengthen the link between diet and gastrointestinal health outcomes. Objective: The present study aims to characterize the monosaccharide composition of diets in a healthy U.S. adult cohort and use these features to assess the relationship between monosaccharide intake, diet quality and characteristics of the gut microbiota. Design: This observational, cross-sectional study enrolled males and females across age and BMI categories. Recent dietary intake was assessed by the automated self-administered 24-hr dietary recall system (ASA24) and gut microbiomes were assessed with shotgun metagenome sequencing. Dietary recalls were mapped to the Davis Food Glycopedia (DFG) to estimate monosaccharide intake. Participants with <75% of carbohydrate intake mappable to the glycopedia were excluded (N = 180). Results: Diversity of monosaccharide intake were positively associated with the total Healthy Eating Index (HEI) score (Pearson’s r = 0.518, p = 1.5e-13) and negatively associated with fecal neopterin (Pearson’s r = -0.253, p = 2.0e-3) Comparing high vs. low intake of specific monosaccharides revealed differentially abundant taxa which correlated with the functional capacity to breakdown fibers comprised of these monomers. Conclusions: This population-based observational study supports that assessment of carbohydrate intake at the level of monosaccharides can be used to new dietary features and fine-tune the assessment of diet-gut microbial structure and function. This trial is registered at www.clinicaltrials.gov as NCT02367287