Knowing specific foods that are helpful or harmful is one thing, the challenge is to find the strength to act on it. Serious sweet tooth speaking here!
If you are at Level II, a lot of work with mental/emotional symbol can be helpful for this. But shoot, don't go by me, I'm still working on this topic myself. For me, weight is not as much the issue as inner balance, digestive peace or lack of it, inflammation and resulting back pain & other afflictions.
Best I can do is follow earth-guidance on good foods to eat, and not beat myself up for slipping and eating sweets.
Blessings,
Aronaya