Effects of zinc, vitamin D, and their co-supplementation on mood, serum cortisol, and brain-derived neurotrophic factor in patients with obesity and mild to moderate depressive symptoms: A phase II, 12-wk, 2 × 2 factorial design, double-blind, randomized, placebo-controlled trial.

OBJECTIVE: The aim of this study was to investigate the effects of zinc, vitamin D, and their co-supplementation versus placebo on changes in the Beck Depression Inventory II (BDI-II) score, serum cortisol level, and brain-derived neurotrophic factor (BDNF) in obese/overweight patients with depressive symptoms. METHOD: This 2 × 2 factorial, double-blind, randomized, placebo-controlled trial with obese/overweight patients with depressive symptoms was conducted in the Endocrinology and Metabolism Research Center (EMRC), Vali-Asr, Emam Khomeini Hospital between July 2016 and February 2017. The intervention period was 12 wk. There were 140 randomized participants who were obese or overweight (mean ± SD, 38.35± 6.70 y of age; mean ± SD body mass index, 30.1 ± 3.78 kg/m2) with BDI ≥ 10. Participants were randomly assigned to one of four groups in a 1:1:1:1 ratio: 2000 IU/d vitamin D + zinc placebo; 30 mg/d zinc gluconate + vitamin D placebo; 2000 IU/d vitamin D + 30 mg/d zinc gluconate; or vitamin D placebo + zinc placebo for 12 wk. RESULTS: We analyzed 125 participants, and a significant decrease in BDI-II was found among those who received zinc, vitamin D, or joint zinc-vitamin D supplements compared with the placebo group (P < 0.001). Zinc was significantly more effective than vitamin D on decreasing the depression score. Supplementation with zinc, vitamin D, or a combination of the two had no significant effects on serum cortisol (P = 0.974) or BDNF (P = 0.076). Fifteen patients discontinued participation owing to pregnancy (n = 1), severe anemia (n = 1), and unspecified unwillingness to continue (n = 13). CONCLUSION: Supplementation with zinc, vitamin D, or in combination for 12 wk yielded significant beneficial effects on the BDI-II score in obese or overweight patients with BDI-II ≥10.

Effect of vitamin D supplementation as adjunctive therapy to methylphenidate on ADHD symptoms: A randomized, double blind, placebo-controlled trial.

OBJECTIVES: Previous studies have shown that serum levels of vitamin D were lower in attention deficit hyperactivity disorder (ADHD) children compared to healthy controls. The aim of the study was to determine the effect of vitamin D supplementation as adjunctive therapy to methylphenidate on symptoms of children with ADHD. METHODS: Sixty-two children aged 5-12 years with a diagnosis of ADHD based on DSM-IV criteria were randomly assigned into two groups to receive either 2000IU vitamin D or placebo in addition to methylphenidate for 8 weeks. Symptoms severity was assessed by Conner's Parent Rating Scale-Revised[S] (CPRS), ADHD rating scale-IV (ADHD-RS), and Weekly Parent Ratings of Evening and Morning Behavior (WPREMB) at weeks 0, 4, and 8. Serum levels of 25(OH)D were measured at baseline and after 8 weeks. Anthropometric variables, dietary intake, physical activity, sun exposure, and side effects were assessed. RESULTS: Fifty-four participants completed the trial. After 8 weeks of supplementation, serum levels of 25(OH)D significantly increased in the vitamin D group. ADHD symptoms decreased significantly in both groups (P < 0.05). Evening symptoms and total score of WPREMB scale were significantly different at weeks 4 and 8 between the two groups (P = 0.013, 0.016, respectively), but no differences were found in symptoms by CPRS and ADHD-RS scales. DISCUSSION: Vitamin D supplementation as adjunctive therapy to methylphenidate improved ADHD evening symptoms. Future research is needed to clarify vitamin D effects as monotherapy in ADHD and its mechanism. The trial was registered in www.irct.ir is (IRCT201404222394N10).

Zinc monotherapy increases serum brain-derived neurotrophic factor (BDNF) levels and decreases depressive symptoms in overweight or obese subjects: a double-blind, randomized, placebo-controlled trial.

OBJECTIVE: Previous studies have shown a positive effect of zinc as an adjunctive therapy on reducing depressive symptoms. However, to our knowledge, no study has examined the effect of zinc monotherapy on mood. The aim of the present study was to determine the effects of zinc monotherapy on depressive symptoms and serum brain-derived neurotrophic factor (BDNF) levels in overweight or obese subjects. METHODS: Fifty overweight or obese subjects were randomly assigned into two groups and received either 30 mg zinc or placebo daily for 12 weeks. At baseline and post-intervention, depression severity was assessed using Beck depression inventory II (BDI II), and serum BDNF and zinc levels were determined by enzyme-linked immunosorbent assay and atomic absorption spectrophotometry, respectively. RESULTS: The trial was completed with 46 subjects. After a 12-week supplementation, serum zinc and BDNF levels increased significantly in the zinc-supplemented group compared with the placebo group. BDI scores declined in both the groups at the end of the study, but reduction in the zinc-supplemented group was significantly higher than the placebo group. More analysis revealed that following supplementation, BDI scores decreased in subgroup of subjects with depressive symptoms (BDI ≥ 10) (n = 30), but did not change in the subgroup of non-depressed subjects (BDI < 10) (n = 16). Moreover, a significant inverse correlation was observed between serum BDNF levels and depression severity in all participants. Interestingly, a significant positive correlation was found between serum BDNF and zinc levels at baseline. CONCLUSION: Zinc monotherapy improves mood in overweight or obese subjects most likely through increasing BDNF levels.