I will echo what others have said. Yes she can eat whatever she wants, but it's not recommended. If she is looking to follow a primal lifestyle, she should be choosing whole foods. Real fats, good protein and good carbs. She should also follow her hunger as a guide vs worrying about the macros and calories. She may need more calories than 1800/day with her activity level. Tell her to eat when she's hungry and to not/stop when she's satisfied and to choose whole foods.
Starting Weight: 208 lbs
Current Weight: 166.8 lbs