Study aim: 1. Comparison of changes in serum calcium diol, parathyroid, calcium and phosphorus levels between the three groups. 2. Comparison of changes in waist circumference, weight and body mass index between the three groups 3. Comparison of changes in body fat percentage, body weight (kg), fat mass (kg), visceral fat percentage, visceral fat mass (kg), and fat mass index between the three groups 4. Comparison of changes in height, weight and head circumference of infants in nursing mothers between the three groups 5. Comparison of different infections of the infant (tympanum-nose-eye-throat) between the three groups 6. Comparison of the frequency of visiting a doctor in the newborn between the three groups Design: In this study, 90 mothers who are admitted to Dehkhoda Hospital for delivery are selected. Patients are randomly assigned to three interventions and control groups . Settings and conduct: This study is a double-blind randomized clinical trial on mothers in Dehkhoda Hospital in Qazvin province. Participants/Inclusion and exclusion criteria: All lactating mothers who have a BMI higher than 25, have no illnesses. They also express that they are breastfeeding their infants. Intervention groups: 90 nursing mothers are divided into three groups of 30. Group 1: Placebo Group II: (2000 IU / d) Third group: (4000 IU / D) high limit without risk of taking vitamin D (IOM). Main outcome variables: Effect of vitamin D supplementation on serum Calcidiol, anthropometric measures and body composition in overweight or obese nursing mothers