Based on evidence demonstrating that gut microbiota can metabolize dietary polyphenols to more readily absorbable phenolic acids, this study aimed to evaluate the association of urinary microbial phenolic metabolites (MPMs) related to peanut intake with memory function and stress response. A total of 63 healthy young adults from a randomized controlled trial completed the intervention, consuming 25 g of skin roasted peanuts, 32 g of peanut butter, or 32 g of a control butter daily for six months. Cognition and mood were assessed using validated tests. Urinary cortisol was quantified by an enzymatic method and MPMs were analyzed by liquid chromatography coupled to mass spectrometry.