Abstract Background: Overweight and obesity are defined as abnormal or excessive fat accumulation that may impair health. Body mass index (BMI) is a simple index of weight-for-height that is commonly used to classify overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of his height in meters (kg/m2). Aim of Study: Our study was conducted to assess serum zinc level before and after low carbohydrate diet program over 40 days. Patients and Methods: The study included 30 overweight and obese students with age range from (20-26 years) 22 females and 8 males selected randomly from Faculty of medicine Ain Shams University during 2019-2020 after ex-clusion of students with body mass index below 25kg/m2 and students with constipation, fatigue, diarrhea, heartburn, gas, nausea, vomiting, appetite changes or headache. Results: Serum zinc levels in overweight and obese students were low, most of participants have zinc deficiency which improved with the decrease of BMI after low carbohy-drate diet program this ensures that serum zinc levels affected by body weight and body mass index. Our single arm open label clinical trial showed that serum zinc level improved with decrease in body mass index among overweight and obese medical students after applying low carbohydrate diet program over the same period of time. Conclusion: Taken together the benefits of carbohydrate restriction in overweight/obese patients and the altered serum zinc levels in these patients, it was tempting to further serum zinc levels before and after low carbohydrate diet in overweight and obese youth, where to our knowledge, this is the first clinical study targeting this subject in Egypt.