An objective of this invention is to provide a novel detecting or evaluating method for easily and accurately detecting or evaluation blood flow state, which uses a biochemical index , without surgically removing skin thereby stimulating skin. An evaluating method or indirect measuring method for blood flow uses expression amount of interleukin-1 receptor antagonist and/or interleukin-1 α in skin horny layer as an index.本發明的課題係提供不是外科摘取皮膚而對皮膚帶來刺激等的方法，而是可簡便且確實地測定或評價血流狀態的使用生物化學指標的新穎的測定或評價方法。一種皮膚血流量的間接測定或評價方法，其係以皮膚角質層中的白細胞介素-1受體拮抗劑及/或白細胞介素-1 α的表現量作為指標。
