It does sound like hereditary neuroses - you Lab sounds similar to a Sheltie I know, both in her fear of noises and in her endless eating. I do not know anything you can do about the eating, other than getting tall trash cans with lids so she cannot get to stuff she shouldn't eat, and being careful about where you put food - the staff at the office with the Sheltie has learned that the humans have to be responsible, because the dog just won't be!
As for her fear of noises, I think just reassuring her that she is safe, and loved, is all you can do. As a child my family had a very smart dog who was so scared during storms that she would "sneak" into someone's bed for comfort. She wasn't afraid of anything else, was the lead dog in the neighborhood "pack" and guard of the family children against anything, but thunderstorms reduced the poor baby to quivers! So we just snuck her into bed for the storm, and sympathized!
Anybody have any ideas for Belle?