Efficacy of oral Vitamin D supplementation in reducing body mass index and lipid profile in adolescents and young adults in Colombia: A pilot clinical trial protocol nested in the SIMBA cohort

口服维生素D补充剂对降低哥伦比亚青少年和青年体重指数和血脂水平的疗效：一项嵌套于SIMBA队列的试点临床试验方案