Breastfeeding & Weight Loss

Hi, ladies! So let me start off with a back story. I'm 23 y/o (24 in 2 weeks), with a 2 1/2 year old and a 7 month old (who I am still breastfeeding). Before I got pregnant with my first, I weighed 130lbs and was in a size 2-4 jeans depending on brand. I got down to 128lbs 12 months PP after my first baby but my hips never went back so I was wearing a 5-6 at this point. Now I'm 7 months pp after baby #2, no idea on my weight (last time i checked was 145lbs), but I'm in a size 10 jeans!! Going from a 2 to a 10 sucks! I know my hips will never go back but I wanna lose weight and tone/tighten my body. Any advice on diet while breastfeeding? I don't wanna tank my supply. I normally eat a ton of junk/unhealthy foods so I'm "shelf cooking" til i run out of food.