SP uses the percentage guidelines for protein, fat and carbs from the Dietary Reference Intakes from the Institute of Medicine. We do set a minimal amount for protein of 60 grams for females and 75 grams for males since weight loss research does show that it helps maintain muscle mass and promote satiety. This SP articles gives all the details: www.sparkpeople.com/resource/nutrition_art
Let me know if you have more questions on this.
SP Dietitian Becky