Vitamin D Levels in Psoriasis Patients
Direct Answer
Oral vitamin D supplementation is NOT recommended for the treatment of psoriasis, as it does not directly improve disease activity at dosages that avoid hypercalcemia and calciuria. 1 The focus should be on topical vitamin D analogues (calcipotriene, calcitriol) rather than measuring or correcting serum vitamin D levels for psoriasis management.
Key Clinical Guidance
Topical vs. Oral Vitamin D
Topical vitamin D analogues are highly effective for psoriasis treatment, with 70-74% of patients achieving marked improvement or clearing with calcipotriene ointment versus 18-19% with placebo. 1
Oral vitamin D supplementation does not improve psoriasis severity at safe doses, despite the proven efficacy of topical formulations. 1
The American Academy of Dermatology explicitly states that rather than adding oral vitamin D supplementation, topical therapy with vitamin D agents should be used for psoriasis treatment. 1
Serum Vitamin D Levels: What the Research Shows
While guidelines do not recommend targeting specific serum vitamin D levels for psoriasis treatment, research reveals important patterns:
Psoriasis patients have significantly lower vitamin D levels than healthy controls (mean 19.6-28.3 ng/mL vs. 23.6-37.9 ng/mL). 2, 3
Vitamin D deficiency occurs in 60% of psoriasis patients versus 17.5% of controls, with a 3-fold increased odds ratio for deficiency. 2, 4
Lower vitamin D levels correlate inversely with disease severity (PASI scores), though this association does not justify oral supplementation for psoriasis treatment. 2, 3
Why Oral Supplementation Doesn't Work for Psoriasis
The disconnect between topical efficacy and oral ineffectiveness is critical:
Meta-analysis shows oral vitamin D supplementation produces non-significant improvements in PASI scores after statistical adjustment (MD = -0.92,95% CI = -2.21 to 0.38). 5
The therapeutic mechanism of topical vitamin D analogues is local anti-inflammatory and antiproliferative effects on keratinocytes, not systemic vitamin D repletion. 1
Doses of oral vitamin D sufficient to impact psoriasis would risk hypercalcemia and calciuria. 1
Recommended Treatment Approach
First-Line Topical Therapy
Use calcipotriene combined with betamethasone propionate as the gold standard, with 48% achieving absent or mild psoriasis at 4 weeks versus 7.6% with placebo. 1
For sensitive areas (face, eyelids, ears), combine calcipotriene with lower-potency corticosteroids like hydrocortisone rather than betamethasone. 6, 7
Long-term use (up to 52 weeks) of vitamin D analogues combined with corticosteroids is supported by Grade A evidence. 6
When to Check Vitamin D Levels
Do not routinely measure serum 25(OH)D levels for psoriasis management, as correcting deficiency does not improve psoriasis outcomes. 1
Consider checking vitamin D only for general health screening in patients with risk factors for deficiency (limited sun exposure, malabsorption, chronic kidney disease), not for psoriasis-specific reasons.
Common Pitfalls to Avoid
Do not prescribe oral vitamin D supplements expecting psoriasis improvement—this is ineffective and may create false expectations. 1, 5
Do not confuse the efficacy of topical vitamin D analogues with a need for systemic vitamin D repletion—these are separate mechanisms. 1
Avoid exceeding 100 g/week of topical calcipotriene due to risk of reversible hypercalcemia. 1
Never use high-potency topical vitamin D/corticosteroid combinations on sensitive areas without appropriate potency adjustment. 6, 7
Patient Counseling
Explain that while their blood vitamin D levels may be low, oral supplements will not improve their psoriasis, though they may benefit overall bone and immune health. 1
Emphasize that topical vitamin D medications work through direct skin effects, not by raising blood vitamin D levels. 1
Many patients ask about vitamin D supplementation for skin health—redirect this conversation toward proven topical therapies. 1