The best oils for psoriasis are ones high in omega-3 essential fatty acids. The reason for this is because omega-3s have been shown to help treat psoriasis.
Chia oil, echium oil, and flaxseed oil are all high in omega-3, and can be applied topically to psoriasis-prone skin.
Ingredients like olive oil and avocado oil should not be used on the skin, as these can worsen conditions like psoriasis.