Probiotics and the Gut–Skin Axis: A Systematic Review of Microbial Pathways Underlying Psoriasis and Immunoinflammatory Balance

Javad Karimi ¹*, Bahareh Nowruzi ², Mansoureh Nazari ³

This review elucidates how gut microbiota influence psoriasis and highlights probiotics as a promising complementary approach to reduce inflammation and improve outcomes.

Abstract

Psoriasis, a chronic autoimmune skin disorder, extends far beyond the surface of the skin. Emerging research has revealed that its origins may lie deep within the gut, where microbial imbalance—or dysbiosis—can disrupt immune regulation and fuel chronic inflammation. This systematic review explores the intricate relationship between gut health and psoriasis, emphasizing how probiotics may help restore balance and reduce inflammatory responses. The “gut–skin axis” acts as a vital communication channel between intestinal microbiota and skin health. When this connection is compromised, toxins and inflammatory signals can enter systemic circulation, aggravating skin lesions and immune dysfunction in psoriatic individuals. Recent studies highlight that certain probiotic strains, particularly Lactobacillus and Bifidobacterium, show promise in reinforcing the intestinal barrier, modulating cytokine production, and ultimately easing psoriatic symptoms. Beyond biological mechanisms, this review underscores a paradigm shift in how psoriasis is understood and treated—shifting from symptom suppression to root-cause management. Probiotic therapy, when integrated with conventional treatments, offers a holistic, low-risk approach that may enhance overall well-being and reduce disease burden. By synthesizing evidence from clinical and experimental studies, this paper advocates for further exploration of probiotics as a complementary intervention for psoriasis. Understanding how gut microbiota influence immune function not only expands therapeutic options but also opens the door to a more integrative, patient-centered model of care.

Keywords: Psoriasis, Probiotics, Gut–Skin Axis, Dysbiosis, Chronic Inflammation, Microbiome, Autoimmune Disorder, Holistic Therapy

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