I’d ask chat gpt for a healthy meal plan for your daughter and start as soon as possible. You don’t want to start her on a path to obesity but also without triggering a food disorder.
Cut out processed foods and give her fibre, protein, fruit, water and vegetables. So porridge/yoghurt/fruit/weetabix/bran flakes for breakfast. Sandwiches/toast/jacket potato for lunch with salad, with good yoghurt or muller rice pudding pots and fruit. Dinner can be anything with wholewheat and fibre e.g chicken curry with brown rice and mini naan, spaghetti bolognaise with added mushrooms. Brown pasta with tomato sauce, cheese and broccoli. Jacket potato with tuna and mayo and sweetcorn. If she wants a snack it can’t be crisps, offer pretzels or rice cakes (there are lovely flavours including some covered in a bit of chocolate!). Yoghurts, rice pudding/jelly pots/fruit pots are good too. Fruit and yoghurt are great for snacks. If she’s really hungry then a slice of buttered toast.
Do you want to see someone about your disordered eating? You could ask the GP for a referral. I was raised on an awful diet and became obese by age 10. people’s comments about my weight triggered an eating disorder where I starved myself often.
When I was a teenager, a lady taught me about healthy eating and it changed my life. Instead of swinging from bad foods to nothing, I replaced it with fruit, vegetables, salads, protein, fiber. For the first time I replaced all tea&pop with water. I felt amazing for the first time in forever. I’ve stuck to it for 30 years and my children are healthy. I wish you all the very best.