Hi Tiger Mom,
If you are finding that the meals fill you up too much, then just decrease your portion size. (It's not a bad thing!) However, you do want to make sure that you aren't getting too FEW calories per day because your body needs them to fuel your workouts and as you've mentioned, stabilize your blood sugar levels. In those cases, substitute in several small, balanced snacks throguhout the day such as a light protein shake or bar, apple and cheese or bananna and peanut butter, yogart and low-fat granola, nuts and raisins, etc.
I hope this helps. If you have further questions about your dietary needs, you can also reach out to the online dietician who can give you a response more tailored to yuor specific caloric needs.
Good Luck,
Paul