IL17A and Erythema: The results from the present study have revealed that endogenous lowering of the n-6/n-3 ratio and higher n-3 PUFA levels not only suppresses Th17 cells and maintains the level of anti-inflammatory cytokines Foxp3 from Treg cells, but also inhibits the expression of pro-inflammatory or inflammatory cytokines, including IL-17, IL-22 and IL-23 in the serum, preventing their accumulation in the lesion, and subsequently reducing thickening, erythema and scales.