If you want to lose a little weight, I recommend that you cut back on all the empty carbs you may be eating. Bread, pastas, crackers, buns, cereals and potatoes. However, you must not go hungry, and you must eat enough proteins, vegetables, salads, fruits, and healthy fats.
You don't want to lose any muscle mass, or visceral fat - the fat that protects your organs. Some dancers weigh too little - oh yes.
Here are some tips to keep this all in a healthy perspective:
How To Lose Some Weight and Keep It Off this article has a link to protein calculator;
What Ballet Dancers Need To Understand About Weight Loss and Calories
What Is Your Protein Requirement
Learning To Develop Lean Muscles
Healthy Fats For Ballet Dancers