This study is an interactive web-based randomized trial on 160 people with metabolic syndrome in Tehran. The aim of this parallel randomized controlled trial is comparison the effectiveness of an interactive web-based lifestyle intervention focusing on dietary and physical activity for reducing metabolic syndrome indicators. A website namely Healthy Heart Education (http://www.Heartresearch.ir) is designed in order to increase knowledge of visitors about cardiovascular diseases risk factors and attract the attention for metabolic syndrome. Participants enrolled to the study by registering on the website and completing information including: name, age, gender, weight, height, waist circumference, phone number, living home addresses. Participants who meet the study criteria contacted and invited for the study. Randomization carried out after baseline measurements. Participants randomly assigned to two arms. All participants received information on dietary intake and physical activity through the study website. The intervention group received additional resources via the study website including interactive Healthy Heart Profile and calorie restricted diet tailored to the participants. Participants in the intervention group receive username and password to use the Healthy Heart Profile program. The primary outcome is to detect differences in metabolic syndrome between the intervention and the control group. The secondary outcomes are comparing quality of life, physical activity and food intake among the study arms. The participants followed up for 6 months with data collection scheduled at baseline, 3 and 6 months. Anthropometric and clinical measures were (weight, waist circumference, BMI and blood pressure, Total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, Fasting blood glucose.