Psoriasis, like many disorders involving the immune system, is somewhat effected by emotional stress. Some people with psoriasis report that their psoriasis first appeared or worsened after a stressful life event.
Mindfulness meditation to reduce stress can be beneficial in psoriasis. In one study, published in the journal Psychosomatic Medicine, people with psoriasis were treated with ultraviolet light therapy. Some received their treatments while listening to meditation tapes, others received just the light. Patients receiving both cleared their psoriasis up to 4 times faster.

