Comparing the outcomes in the iron supplementation group before and after treatment, significant increases were observed in Hb (9.9 ± 0.8 g/dL vs. 11.9 ± 1.6 g/dL) and Ht (32.3% ± 2.1% vs. 37.1% ± 4.3%), but no significant differences were observed in CFS and VAS-A scores and serum iron, ferritin, or PSQI values. Here, GSTM1 is linked to myalgic encephalomeyelitis/chronic fatigue syndrome.