Sure, it’s a small research study and I only have the abstract.
Anyway, a reduced-calorie diet led to loss of 15 kg (33 lb) over 16 weeks. Over the next 48 weeks, dieters only regained 5 kg (11 lb). (But, hey. Diets don’t work, right?)
It’s possible the specific diet itself lead to the psoriasis improvement, but the researchers don’t make that claim in the abstract. They credit the long-term weight loss:
“Long-term weight loss in patients with psoriasis has long-lasting positive effects on the severity of psoriasis.”
Source: Long-term effects of weight reduction on the severity of psoriasis in a cohort derived from a randomized trial: a prospective observational follow-up study
Psoriasis is an inflammatory disease. Go onto a low inflammation diet (keto) and you will reduce the symptoms considerably, if not stop it altogether :))