Yes, we know that because she was living with Krystle and she was forced to do housework and didn't have access to inhuman amounts of food. Krystle's parents prepared most of their meals. They'd eat out occasionally during that time, but it was mostly controlled. Now, she had started gaining it back when she started her channel, though because I guess she got a bit more comfortable and they were given a pretty generous allowance or stipend or whatever with no bills to pay. It's all been downhill from there.
ETA:
@Aldora is correct, though. She still had a junk food addiction, but Krystle's parents didn't allow her to eat enough at one sitting to feed a small island nation. That's why she'll insist that she can eat white rice and other carby things and lose weight because she lost the mystical 89 elbees doing that. The only difference is portion control.