Background: Psoriasis is a chronic, immune-mediated skin disease. It affects skin and joints, characterized by abnormal hyperproliferation of keratinocytes. The worldwide prevalence of psoriasis ranges from 2% to 4%. Environmental factors as smoking, alcohol consumption obesity can also work as triggers. During the inflammatory process, there is an exacerbated formation of free radicals and antioxidants are required to maintain redox balance. Aim: Assess antioxidant profiles. Methods: A cross-sectional study was conducted between August/2012 and March/2014. Sociodemographic, lifestyle, and biochemical measurements, dietary intake, serum lycopene and α-tocopherol, psoriasis severity according to Psoriasis Area and Severity Index were obtained. Comparisons between serum lycopene and α-tocopherol distributions according to variables were conducted using a one-way analysis of variance. Multiple linear regression was used to investigate factors associated with serum antioxidants. Results: 81 participants (56% female, 62% non-white), 34% without psoriatic lesions, 51% diagnosed with mild psoriasis, and 15% with moderate psoriasis. Median (IQR) age of 54 (41, 62) years, 10 (4, 11) years of education, 17% smokers, 46% overweight and 25% obesity. In total, 72% did not reach the daily recommendation of fruit and vegetable intake. Serum lycopene and α-tocopherol were 0.2 (0.1–0.3) µmol/L and 22.5 (18.5–25.6) µmol/L, respectively. Only 14% presented adequate concentration of lycopene, but adequate α-tocopherol level was observed among 88%. Conclusions: Patients reported a diet low in vegetables and fruits and rich in ultra-processed foods and fatty acids. Adequate circulating α-tocopherol but low serum lycopene, was observed among patients. A linear trend was observed for lycopene according to the severity of psoriasis.

Background: Folic acid fortification program has been established to prevent tube defects. However, concern has been raised among patients using anti-folate drug, i.e. psoriatic patients, a common, chronic, autoimmune inflammatory skin disease associated with obesity and smoking. Objective: To investigate dietary and circulating folate, vitamin B12 (B12) and homocysteine (hcy) in psoriatic subjects exposed to the national mandatory folic acid fortification program. Methods: Cross-sectional study using the Food Frequency Questionnaire, plasma folate, B12, hcy and psoriasis severity using the Psoriasis Area and Severity Index score. Median, interquartile ranges (IQRs) and linear regression models were conducted to investigate factors associated with plasma folate, B12 and hcy. Results: 82 (73%) mild psoriasis, 18 (16%) moderate and 12 (11%) severe psoriasis. 58% female, 61% non-white, 31% former smokers, and 20% current smokers. Median (IQRs) were 51 (40, 60) years. Only 32% reached the Estimated Average Requirement of folate intake. Folate and B12 deficiencies were observed in 9% and 6% of the blood sample respectively, but hyperhomocysteinaemia in 21%. Severity of psoriasis was negatively correlated with folate and B12 concentrations. In a multiple linear regression model, folate intake contributed positively to 14% of serum folate, and negative predictors were psoriasis severity, smoking habits and saturated fatty acid explaining 29% of circulating folate. Conclusion: Only one third reached dietary intake of folate, but deficiencies of folate and B12 were low. Psoriasis severity was negatively correlated with circulating folate and B12. Stopping smoking and a folate rich diet may be important targets for managing psoriasis.