Relation Between Total Polyphenol Intake and Markers of Intestinal Health in Obese Humans

Objectives Polyphenol intake has been associated with improved health outcomes, but the relation between polyphenol intake, gastrointestinal health, and systemic health outcomes is not fully known. Many polyphenols become bioavailable once transformed into metabolites by the gut microbial community. Thus, it is reasonable to assume that the intimate interaction between polyphenols and microbiota may influence both gastrointestinal and systemic health. The objective of the current study was to assess the relation of daily polyphenol intake with intestinal permeability, microbiota profile, and fecal short-chain fatty acids in a sample of obese humans. Methods The analyses were conducted among 92 adult obese participants (body mass index ≥ 30 kg/m2). Polyphenol intake was calculated from a food frequency questionnaire (VioscreenTM) using Polyphenol-Explorer and published literature. Intestinal permeability was measured through collection of 24-hour urine after consumption of a sugar mixture and presented as sucralose and sucralose: lactulose excretion as a % of the oral dose. Microbiota profile and short-chain fatty acids (SCFA) were assessed using 16S sequencing and gas chromatography, respectively. Associations of polyphenol intake between intestinal health markers were examined by correlational analyses; all analyses were conducted using SPSS (version 26). Results Mean age of participants was 44.1 ± 11.3 years; 70.7% were females and 63.0% self-identified as Black/African American. Daily polyphenol intake was 2,733 ± 2,129 mg/day. Primary food group contributors to polyphenol intake were drinks (coffee/tea; 33.2%), fruit (23.9%) and vegetarian protein sources (nuts/seeds/legumes; 15.6%). Total polyphenol intake was positively correlated with fecal butyrate (µg/g) (rho = 0.255; p = 0.029) and butyrate: SCFA ratio (rho = 0.274, p = 0.018). However, polyphenol intake was not correlated to microbiota taxa or markers of intestinal permeability (P > 0.05). Conclusions Dietary intake of polyphenols are associated with fecal SCFA concentrations, but further investigation through intervention studies is needed to elucidate the potential relation between polyphenols and markers of gastrointestinal health. Funding Sources Supported by the Agriculture and Food Research Initiative from the USDA National Institute of Food and Agriculture.