I don't know if potatoes would be a good idea. It's a starch and depending on how it's cooked could be a simple carboydrate. When I eat any type of carb or Sugar the parasites really become active. If I do happen to eat anytype of carb then I put alot of hot stuff on there. Habanero sauce and possibly eat it with ginger. I have spoken to people about putting msm in a drink that had lots of Sugar to help the parasites absorb more of the msm. I use the same reasoning with the hot peppers. I react very negatively to most carbs. I certainly wouldn't recommend it without an antiparasitic element taken with it.
This person will need to keep her minerals her being depleted.