Research

Mixed

High consumption of ultra-processed foods (UPFs) is associated with specific alterations in gut microbiota composition, including decreased Lachnospira and Ruminococcus species and increased Prevotella species, though effects on overall microbial diversity (alpha/beta) are inconsistent across studies.

If you consume a high amount of ultra-processed foods, you may see a shift in your gut bacteria, specifically a decrease in beneficial fiber-fermenting types like Lachnospira and an increase in Prevotella. While overall diversity might not change significantly in all cases, these specific shifts are linked to higher UPF intake. To support a healthier microbiome, consider reducing UPF intake and increasing fiber-rich whole foods.

ModerateQualifiesMEDIUM confidence
Two studies identified increased Prevotella spp. [17,19] and two studies identified decreased Lachnospira spp. [16,19] and Ruminococcus spp. [18,19] with increased UPF consumption.
Allison L. Brichacek et al. · Nutrients · 2024

Why this rating

Based on four observational studies with varying methodologies and inconsistent findings on diversity metrics.

Source

Ultra-Processed Foods: A Narrative Review of the Impact on the Human Gut Microbiome and Variations in Classification Methods

Allison L. Brichacek et al. · Nutrients · 2024

DOI 10.3390/nu16111738

narrative_reviewCited 41×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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