GDF15 and sarcopenia: Moreover, after reviewing the studies focusing on the relationships between cytokines, growth factors and sarcopenia, many factors, including IL1b, IL6, IL8, IL17 (interleukin‐17), TNFa, TGF1, GDF‐15 (growth differentiation factor‐15) and so on, may all relate to sarcopenia.18, 20, 21, 22