My client lost 6kg in 12 weeks by following her CBT program meticulously. Nutrition involved a 400 calorie deficit with a macronutrient breakdown of 40% carbohydrate, 40% protein and 20% fat. Exercise involved training weights 3x a week and minimal cardio.
So much is possible in a such a short period of time. All this took was 50 workouts and 250 meals.