Regardless of age or gender, the basics of healthy diet are the same for anyone:
- Eat a variety of different foods
- Try to get your calories from about 40% carbs, 30% protein, and 30% fat
- Eat enough food, but don't overeat
- Drink pleanty of water
- Eat a lot of fruits and veggies
So assuming you are on a 1500 calorie diet (which is probably about right for a 13 year old girl), you would want to break that up roughly like this:
- 150g carbs (150g carbs * 4cals/g carbs = 600cals)
- 112g protein (112g protein * 4cals/g protein ~= 450cals)
- 50g fat (50g fat * 9cals/g fat = 450cals)
