| Magnesium and melatonin are known to exert multiple beneficial effects including anti-inflammatory and antioxidant actions. This study was designed to determine the effects of magnesium and/or melatonin supplementation on metabolic profiles in women with polycystic ovary syndrome (PCOS). This randomized double-blind, placebo-controlled trial was conducted among 84 subjects with PCOS aged 18–40 years old. Patients were randomly assigned based on the random block procedure to take magnesium, melatonin, magnesium plus melatonin, or placebo for 8 weeks. Fasting blood samples were taken at baseline and after the intervention to quantify related variables. After the 8-week intervention, an insignificant marginal difference was seen in waist circumference (WC) between groups (P = 0.085). Magnesium-melatonin co-supplementation resulted in more reductions in hirsutism compared with other groups (P < 0.001). Serum levels of tumor necrosis factor-α (TNF-α) declined significantly in the melatonin and co-supplementation groups compared to baseline (P < 0.05). Also, magnesium plus melatonin was associated with a more increase in total antioxidant capacity (TAC) levels, as compared to the other treatment groups (P = 0.001). Overall, we found a favorable effect of co-supplementation of magnesium and melatonin for 8 weeks in women with PCOS on hirsutism, serum TNF-α, and TAC levels. Furthermore, melatonin independently contributed to decreased serum values of TNF-α. |