Ultra-Processed Foods: What Science Says About Gut Health Risks

One of the most notable shifts in the 2025–2030 DGAs is the explicit recommendation to avoid highly processed foods — a move critics say is long overdue given mounting scientific evidence.

What Are Ultra-Processed Foods?

Ultra-processed foods (UPFs) are industrial products high in additives, refined starches, added sugars, oils, protein isolates, and tend to contain little, if any, intact whole food — items like sugary drinks, packaged snacks, and fast foods.

Scientific Evidence on UPFs and the Gut

Several studies and reviews from 2024–2025 provide consistent evidence:

• UPFs and gut microbiota: Controlled and observational studies link UPF consumption with alterations in gut microbial composition, decreased diversity, and markers of inflammation.
• Gut dysbiosis and disease risk: Reviews associate UPF intake with dysbiosis — an imbalance in microbial communities — which is implicated in conditions like inflammatory bowel disease and increased gut permeability.
• Clinical findings: Research in populations such as those with systemic autoimmune conditions found that higher UPF intakes correlate with worse gastrointestinal symptoms and changes in microbiota structure.
  
  

Why It Matters

Gut microbes play a key role in metabolizing dietary components and training the immune system. The evidence suggests that high UPF consumption may:

• Reduce beneficial microbes
  
• Promote pro-inflammatory pathways contributing to disease states
• Contribute to metabolic disturbances linked to type 2 diabetes and other chronic conditions

Sources

1. Association between gut microbiota and ultra-processed foods consumption among the patients with type 2 diabetes: a cross-sectional study
   https://nutritionandmetabolism.biomedcentral.com/articles/10.1186/s12986-024-00884-y
2. The link between ultra-processed food consumption, fecal microbiota, and metabolomic profiles in older mediterranean adults at high cardiovascular risk
   https://nutritionj.biomedcentral.com/articles/10.1186/s12937-025-01125-5
3. Five things to know about ultra-processed food
   https://news.stanford.edu/stories/2025/07/ultra-processed-food-five-things-to-know/
4. Fermented Foods, Health and the Gut Microbiome
   https://pubmed.ncbi.nlm.nih.gov/35406140/