I think that the aim of Yoga is to achieve relaxation. Some people eat when they are anxious. In this case, I think Yoga can help, but indirectly. But, I don't think there is any relation between Yoga and weight loss.
Ms. Harpersays said that Yoga increases oxygen in the blood. And, I agree with that but I don't think more oxygen means more fat consumed and hence losing weight.
Indeed, more oxygen equals more energy as a result of efficient metabolism_known as aerobic metabolism which provides folds of energy compared to Anaerobic metabolism with the same amount of food.
So, simply I want to say that I don't know any relation between yoga and weight loss.