Diet Quality and the Fecal Microbiota in Adults in the American Gut Project

Alexis D Baldeon; Daniel McDonald; Antonio Gonzalez; Rob Knight; Hannah D Holscher

doi:10.1016/j.tjnut.2023.02.018

Diet Quality and the Fecal Microbiota in Adults in the American Gut Project

J Nutr. 2023 Jul;153(7):2004-2015. doi: 10.1016/j.tjnut.2023.02.018. Epub 2023 Feb 22.

Authors

Alexis D Baldeon¹, Daniel McDonald², Antonio Gonzalez², Rob Knight³, Hannah D Holscher⁴

Affiliations

¹ Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.
² Department of Pediatrics, University of California San Diego, La Jolla, California, USA.
³ Department of Pediatrics, University of California San Diego, La Jolla, California, USA; Center for Microbiome Innovation, University of California San Diego, La Jolla, California, USA; Department of Bioengineering, University of California San Diego, La Jolla, California, USA; Department of Computer Science and Engineering, University of California San Diego, La Jolla, California, USA.
⁴ Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA; Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA. Electronic address: hholsche@illinois.edu.

PMID: 36828255
DOI: 10.1016/j.tjnut.2023.02.018

Abstract

Background: The Dietary Guidelines for Americans advises on dietary intake to meet nutritional needs, promote health, and prevent diseases. Diet affects the intestinal microbiota and is increasingly linked to health. It is vital to investigate the relationships between diet quality and the microbiota to better understand the impact of nutrition on human health.

Objectives: This study aimed to investigate the differences in fecal microbiota composition in adults from the American Gut Project based on their adherence to the Dietary Guidelines for Americans.

Methods: This study was a cross-sectional analysis of the 16S sequencing and food frequency data of a subset of adults (n = 432; age = 18-60 y; 65% female, 89% white) participating in the crowdsourced American Gut Project. The Healthy Eating Index-2015 assessed the compliance with Dietary Guideline recommendations. The cohort was divided into tertiles based on Healthy Eating Index-2015 scores, and differences in taxonomic abundances and diversity were compared between high and low scorers.

Results: The mean Total Score for low-scoring adults (58.1 ± 5.4) was comparable with the reported score of the average American adult (56.7). High scorers for the Total Score and components related to vegetables, grains, and dairy had greater alpha diversity than low scorers. High scorers in the fatty acid component had a lower alpha diversity than low scorers (95% CI: 0.35, 1.85). A positive log-fold difference in abundance of plant carbohydrate-metabolizing taxa in the families Lachnospiraceae and Ruminococcaceae was observed in high-scoring tertiles for Total Score, vegetable, fruit, and grain components (Benjamini-Hochberg; q < 0.05).

Conclusions: Adults with greater compliance to the Dietary Guidelines demonstrated higher diversity in their fecal microbiota and greater abundance of bacteria capable of metabolizing complex carbohydrates, providing evidence on how Dietary Guidelines support the gut microbiota.

Keywords: ANCOM-BC; Dietary Guidelines; Healthy eating index; Songbird; dietary patterns.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Adolescent
Adult
Cross-Sectional Studies
Diet
Health Promotion*
Humans
Microbiota*
Middle Aged
RNA, Ribosomal, 16S
United States
Vegetables
Young Adult

Substances

RNA, Ribosomal, 16S