It was reported that psoriasis patients often show unbalanced dietary habits such as higher intake of red meat and fat but lower intake of dietary fibers 46, 47, exacerbating psoriasis via the activation of the nucleotide-binding domain, leucine-rich repeat-containing family, TNF-α/IL-23/IL-17 pathway and reactive oxygen species 48, 49. Here, IL17A is linked to psoriasis.