Fine-Scale Dietary Polyphenol Intake Is Associated with Systemic and Gastrointestinal Inflammation in Healthy Adults

Area of Science:

• Nutritional Science
• Biochemistry
• Immunology

Background:

• Dietary polyphenols are bioactive compounds with known anti-inflammatory properties.
• Limited data exists on polyphenol intake at class/compound levels and its link to inflammation.

Purpose of the Study:

• To quantify dietary polyphenol intake in healthy adults.
• To investigate the association between polyphenol intake and gastrointestinal (GI) and systemic inflammation markers.

Main Methods:

• Observational, cross-sectional study of 350 healthy adults.
• Dietary intake assessed via 24-h recalls, mapped to FooDB for polyphenol estimation (total, class, compound).
• Statistical analyses included linear models and random forest regressions.

Main Results:

• Mean total polyphenol intake was ~914 mg/1000 kcal/d; flavonoids were the major class.
• Higher total polyphenol intake was linked to lower fecal calprotectin (GI inflammation marker).
• Specific polyphenol classes (prenol lipids, phenylpropanoic acids) correlated with reduced GI permeability markers.

Conclusions:

• Dietary polyphenol intake is associated with reduced GI inflammation in healthy adults.
• Specific polyphenol classes, like prenol lipids and phenylpropanoic acids, may reduce GI permeability.
• The impact of polyphenols on inflammation is complex and depends on intake resolution (total, class, compound).