In any case, what you want to do is focus on healthy eating behaviors. In spite of the fact that you feel your daughter doesn't eat much, if she is overweight it is likely that she is eating too much, particularly too much of the wrong kinds of foods. The number of meals isn't important; the type of food in each meal is. It would probably be helpful for your daughter and you to meet with a nutritionist, to review her eating habits and get some information about making appropriate food choices. You daughter needs to understand this information, as she is the one who makes food choices when she is away from home. If she's not interested and informed, it's unlikely that she'll make any changes.
It's good that your daughter is active; exercise is an important component of weight control. But consider the type of exercise she's doing. Simply playing outdoors with her friends may not be enough. More vigorous or prolonged exercise may be necessary to help her maintain an appropriate weight. Your physician or a physical therapist could review appropriate exercise guidelines for children her age.