What dietary recommendations are suitable for a patient with psoriasis?

Dietary Recommendations for Psoriasis

For patients with psoriasis, recommend weight reduction through a hypocaloric diet if overweight/obese, omega-3 fatty acid supplementation as adjunctive therapy, and a gluten-free diet only for those with confirmed celiac disease or positive celiac antibodies. 1, 2

Weight Management: The Strongest Recommendation

Weight reduction through a hypocaloric diet is strongly recommended for overweight and obese patients with psoriasis, as this represents the most robust dietary intervention with clear evidence of benefit. 2 This recommendation is based on the established link between obesity and psoriasis severity, as well as the metabolic syndrome components frequently seen as comorbidities in psoriasis patients 3, 4.

• Implement a structured low-calorie diet with nutritionist support for patients with BMI ≥25 kg/m² 2
• This intervention improves both skin disease severity and reduces cardiovascular comorbidity risk 1

Omega-3 Fatty Acids: Evidence-Based Adjunctive Therapy

Add omega-3 fatty acid supplementation to standard topical, phototherapy, or systemic treatments—never use as monotherapy. 1, 5

• The American Academy of Dermatology recommends omega-3 supplementation to augment effects of conventional psoriasis therapies 1, 5
• Select supplements certified free of mercury, dioxins, and polychlorinated biphenyls (PCBs) due to contamination risk 1, 5
• The bleeding risk with fish oil is negligible and does not increase surgical bleeding 1
• Patient surveys show 44.6% report skin improvement with fish oil/omega-3 supplementation 6

Gluten-Free Diet: Only for Specific Patients

Implement a gluten-free diet exclusively in patients with positive celiac antibodies or confirmed celiac disease—do not recommend to all psoriasis patients. 1, 5, 2

Screening and Implementation Algorithm:

• Screen patients with moderate-to-severe plaque psoriasis for celiac disease using serologic markers 1
• If celiac antibodies are positive, refer to gastroenterology for formal diagnosis 1
• Trial a strict gluten-free diet for 3 months in antibody-positive patients, though improvement is not guaranteed 1
• Critical pitfall: Gluten-free diets are highly restrictive and negatively impact quality of life; avoid implementing without clear indication 1, 5
• Mandate nutritionist consultation before eliminating gluten to prevent nutritional deficiencies, especially in patients already following restricted diets 1, 5

Patient surveys show 53.4% of those who reduced gluten reported skin improvement, but this does not justify universal recommendation 6.

Curcumin: Limited Evidence for Adjunctive Use

Consider oral curcumin supplementation as adjunctive therapy for patients with psoriasis of varying severity, though evidence remains limited 1, 5.

• Curcumin modulates T-helper type 22 cell activity and decreases epidermal proliferation 1
• Combine with piperine from black pepper to enhance absorption 1
• Curcumin has low toxicity and poor bioavailability 1

Mediterranean Diet: Emerging Evidence

The Mediterranean diet shows promise for psoriasis management based on its anti-inflammatory properties 7, 3.

• Emphasize extra virgin olive oil, fruits, vegetables, legumes, and whole grains 7
• Patient surveys indicate 42.5% report skin improvement after adding vegetables 6
• This dietary pattern addresses both psoriasis and cardiometabolic comorbidities simultaneously 3

What Does NOT Work: Avoid These Interventions

Do not recommend oral vitamin D supplementation for psoriasis treatment—use topical vitamin D analogues instead. 1, 5

• Oral vitamin D at safe dosages does not improve psoriasis disease activity 1, 5
• Excess supplementation risks hypercalcemia toxicity 1, 5

Do not recommend oral zinc supplementation—it does not improve disease severity scores. 1, 5

Dietary Modifications to Reduce Flares

Advise patients to limit or avoid specific triggers that can precipitate or worsen psoriasis 8:

• Alcohol reduction: 53.8% of patients report skin improvement after reducing alcohol intake 6; alcohol increases risk for severe disease and comorbidities 5
• Avoid nightshades: 52.1% of patients report improvement after eliminating nightshades (tomatoes, peppers, eggplant, potatoes) 6
• Reduce saturated fatty acids and replace with polyunsaturated omega-3 fatty acids 4
• Limit sugar intake 6

Critical Clinical Pitfalls to Avoid

• Never use dietary interventions as monotherapy—always combine with evidence-based topical, phototherapy, or systemic treatments 1, 5
• Never recommend gluten-free diets universally—only for confirmed celiac disease or positive antibodies 1, 5
• Never rely on unproven supplements like ghee that lack scientific evidence 5
• Never implement restrictive diets without nutritional guidance—risk of nutritional deficiencies 1, 5

Antioxidant-Rich Foods: General Recommendation

Encourage intake of antioxidants including vitamin A, vitamin C, vitamin E, carotenoids, flavonoids, and selenium through whole foods 4.

• Psoriasis patients already consume significantly more fruits, vegetables, and legumes compared to controls 6
• This dietary pattern supports overall health and addresses comorbidity risk 6