An Evaluation of the Effect of Vitamin D Supplementation on Depressive Symptoms Among Chinese Adolescents

The goal of this randomized controlled clinical trial is to investigate the effects of vitamin D3 supplementation on depression in Chinese adolescents with elevated depressive symptoms and vitamin D deficiency. The main question it aims to answer whether vitamin D3 supplementation can reduce depressive symptoms. Participants in the intervention group will receive vitamin D3 capsules and mental health education. The control group will receive vitamin D3 placebo and mental health education. Researchers will compare the change in depressive symptoms from baseline to post-intervention at 12 weeks between the intervention and control groups.