© 2015, Grupo Aula Medica S.A. All Rights Reserved. Objective: the aim of this study was to compare an Intensive Lifestyle Intervention against Traditional Treatment for obesity management in the primary care setting. Subjects and methods: interventional randomized controlled study with participation of 42 obese adults. Subjects assigned to the Intensive Lifestyle Intervention received a validated behavior change protocol “Group Lifestyle Balance” in 12 sessions, weekly consultations by a nutritionist and meal replacements. Traditional Treatment consisted of monthly consultations with a nutritionist that provided nutritional assessment and physical activity. Results: almost all study participants (97%) were measured after 3 months of intervention. Intensive Lifestyle Intervention and Traditional Treatment subjects showed the following changes in body weight: (Median [25-75th percentile]) (-4.7 kg [-6.5, -3.1]) vs. (+0.4 kg [-0.3, 1.3]). Sixty two percent of Intensive Lifestyle Intervention group participants lost more than 5 % body weight vs. 0 % in the traditional treatment group (p < 0.001). Conclusions: this preliminary evidence showed that an Intensive Lifestyle Intervention can be an effective strategy for obesity management in the primary care setting.