How much weight loss can be expected while on Concerta?

Though I didn't begin taking it to lose weight, I've definitely had that result. I was 216lbs when I went to the dr. to ask questions about ADD and whether or not I have symptoms and how serious they might be. I was diagnosed with a pretty strong case of ADD (basically my mind is always racing, starting different projects, but not able to avoid distractions and not able to follow through on projects both work and home. Many times having 5 or more things going on my desk at once - juggling back and forth, avoiding tasks that required concentration, etc.) I was prescribed 36mg per day and noticed the impact immediately with the loss of desire to sleep all the time (typically caused by desire to escape the juggling of all of my tasks). I had energy galore, am able to concentrate all day long, read for long periods (boring financial stuff not novels) and retain the information. I also had heartburn and headaches the first few days. After about 5 days, I took a day off from the Concerta and started again the next day. Since that time, I haven't had any side effects whatsoever, other than lots of energy and concentration and a dramatic effect in my productivity. So... the question about weight loss. One month later I went to the dr. as a follow up and was surprised to weigh in at 9lbs less... Since then (only a week ago), I've really began to watch my diet (encouraged by the previous month's results without event trying), count calories and keep a journal of what I eat, exercise daily, and I've dropped another 5-7 lbs already. I'm doing nothing drastic like on Biggest Loser, just 30 minutes of exercise (cardio) plus weight lifting, and eating about 1800 - 2000 calories a day from probably over 3000 a day before. I'm guessing that once I reach my target weight and shape in the next month or two, I'll have to find my target calorie intake that keeps my weight steady since the Concerta will continue to cause my body to burn more calories- I assume that'll be about 3000 calories a day but we'll see... Hope this helps provide info to someone.