Chronic plaque psoriasis is frequently associated with obesity and previous studies have shown that a calorie-controlled diet inducing body weight loss improves symptoms and increases the response to pharmacologic treatment. Besides, clinical improvement has been directly correlated with the amount of weight loss. Short-term very low-calorie ketogenic diets are responsible for substantial weight loss and attenuate systemic inflammation to a higher extent than moderately hypocaloric diets. This intervention has been recently demonstrated to restore, after only 4 week, the response to biological therapy in a patient suffering from relapsing moderate-to-severe plaque psoriasis and obesity-related metabolic syndrome. We investigated the efficacy of an aggressive weight loss program with a ketogenic induction phase in a single-arm trial that could provide the rationale for a large randomized trial.

Inclusion Criteria:

• Stable chronic plaque psoriasis
• Overweight/obese (body mass index >25 kg/m2)

Exclusion Criteria:

• pregnancy and/or lactation
• insulin-dependent diabetes mellitus
• a psychiatric disorder
• current or previous (<1 year since last chemo- or radiotherapy) neoplastic disease
• established vascular disease
• recent (6 months), history of diet-induced or unintentional weight loss
• moderate-to-severe heart failure
• arrhythmia or conduction disorder
• renal failure (creatinine >1.5 mg/dL)
• liver failure (Child-Pugh ≥ A)
• any type of gastrointestinal disease
• moderate-severe hypoalbuminemia (<3.0 g/dL)
• altered serum electrolytes
• refusal to give written informed consent