Yes definitely. But we need to understand that reducing weight is not as simple as losing some "x" amount of calories. In Yoga, the focus is to follow the right lifestyle and the pranic (energy) changes that take place at a much deeper level through constant practice. We need to understand that we are made of matter and energy. When we talk about losing weight we approach only from a matter perspective without understanding the much subtle energetic aspects. Yoga works on the subtle aspects. At a much deeper level, the reason we gain weight is due to some changes in our lifestyle at physical, emotional, physical levels, etc. We need to work on fixing the source through self-awareness gained from Yoga practice.