(P32-31-26) A 6-Week Dietary Intervention Improves Diet Quality and Shows Anti-Inflammatory Potential in Adults With Psoriasis

Objectives: Psoriasis is a chronic inflammatory skin disease with multifactorial etiology involving lifestyle factors; however, evidence for specific dietary strategies remains inconsistent, largely qualitative, and often confounded by weight loss. This pilot study quantified dietary inflammatory potential using the Dietary Inflammatory Index (DII) while assessing changes in diet quality in adults with psoriasis. We hypothesized that a 6-week nutritionally balanced diet would improve Healthy Eating Index-2020 (HEI) scores and produce a  low inflammatory potential dietary pattern, as measured by DII, independent of weight change.

Methods: This feasibility trial enrolled 5 adults with psoriasis consuming a Western diet (HEI ≤ 58), BMI ≥ 25, not receiving biologic therapy in a single arm, unblinded, dietary intervention. Caloric needs for weight maintenance were estimated using the Mifflin-St Jeor equation. Participants received an AHA-, 2020 Dietary Guidelines-, and ADA-aligned diet (3 meals/day, 7 days/week) for 6 weeks to meet most caloric needs. Additional calories were supplied through participant-selected fruits, vegetables, nuts, legumes, and dairy. Weekly behavioral coaching incorporated motivational interviewing. Dietary intake was monitored using photographic food records, analyzed with NDSR. HEI scores were assessed at baseline and end point. DII scores were calculated post-intervention using NDSR and Phenol Explorer.

Results: Mean HEI scores increased from 57–58 at baseline to 73–78 at endpoint. Macronutrient intake aligned with targets, including reduced added sugars and saturated fat and increased dietary fiber.  Body weight remained stable, (±5% of baseline). Endpoint DII scores ranged from -1.95 to -0.49, reflecting a dietary pattern with low inflammatory potential characterized by higher intakes of fruits, vegetables, and polyphenol-rich foods.

Conclusions: A 6-week nutritionally balanced dietary intervention improved diet quality and resulted in a less inflammatory diet pattern. Quantifying dietary inflammatory potential strengthens interpretation of diet and inflammatory disease relationships beyond descriptive dietary patterns within a weight-maintained intervention.

Funding Sources: University of California Davis - Dermatology Department; NIFA U.S. Department of Agriculture (CA-D-NTR-6316-H)