PLICHTA, Miłosz, JAN WANDZEL, ZOFIA WANDZEL, KAMIL KUNECKI, ALEKSANDER URBAŚ, ROZALIA PLICHTA, EMIL PLICHTA, KATARZYNA WILK, PAULINA WIETRZYCKA and WERONIKA ZAJĄC. Fecal Zonulin as a Potential Biomarker of Intestinal Barrier Dysfunction in Obesity: Molecular Mechanisms, Clinical Validation, and Methodological Challenges - Review of Literature. Quality in Sport. Online. 13 August 2026. Vol. 68, p. 74319. [Accessed 30 October 2026]. DOI 10.12775/QS.2026.68.74319.