Relationship of Dietary and Serum Zinc with Depression Score in Iranian Adolescent Girls

Zinc deficiency, which is common among Iranian populations, is believed to play a crucial role in the onset and progression of mood disorders such as depression in different stages of life. We have therefore investigated the relationship between serum/dietary zinc status and depression scores among adolescent girls living in northeastern Iran. Serum zinc was measured by flame atomic absorption (Varian AA240FS) and the mean zinc intake was assessed using 3-day food record. A validated Persian version of the Beck Depression Inventory (BDI) was used to determine the severity of depressive symptoms for all subjects. Data were analyzed using SPSS 18 software. There was a statistically significant correlation between dietary zinc intake and serum zinc concentration (r = 0.117, p = 0.018). Dietary intake of zinc (7.04 ± 4.28 mg/day) was significantly lower among subjects with mild to severe depression symptoms than those with no or minimal depression symptoms (8.06 ± 3.03 mg/day). Dietary zinc intake was inversely correlated with depression score (r = 0.133, p = 0.008). However, there was no significant difference in serum zinc concentrations among individuals with no or minimal and mild to severe depression symptoms (p = 0.5). Dietary zinc intake, but not serum zinc concentration, was inversely associated with depression symptoms. Therefore, controlled clinical trials are needed to determine the efficacy of zinc supplementation in the treatment of depression disorders.