Our bodies always need fat, but play around and find a range that helps you feel and perform at your best. If I could relive my soccer days I would NOT have gone to all-you-can-eat at pizza hut with the team during our two-a-day practices. The second practice after stuffing ourselves silly with pizza always sucked. Keep eating your sweet potatoes, squash and fruit, but don't go purposely avoiding fat. Given your activity level and age, I would not fear fat gain. Soccer workouts are very taxing on the body, so make sure you eat well.