lack of written informed consent;

age \< 18 years old;

history of gastrointestinal, endocrine, pulmonary, kidney, hepatic, and neuromuscular diseases, as well as HIV-positive;

pregnant or breast-feeding women;

previous history of cancer;

use of steroids, protein supplements, vitamins, multivitamins, or antioxidants.

Specific medications to PsA and physical activity were required to be stable for the last 3 months to be included in the study

The DIET Trial - Dietetic Intervention in Psoriatic Arthritis