OK so we have 79 in rescue and 15 pets. At capacity once again... Figured we'd share what we have learned and what we do...
It's actually a pretty simple decision because all you have to do is read some articles, take them to your vet and let the vet help you decide.
We read the ASPCA articles and poison control center articles on renal failure in dogs. We talked to our vet about it. She did some research on her own which was inconclusive, but she was alarmed about the number of deaths in dogs from grapes. (That is very real). She said it's not worth the risk so to avoid grapes. We took her word for it. This vet has a triple degrees including biochemistry and nutrition in addition to the DVM so I reckon she's pretty qualified to hand out that advice.
I don't call this a controversy really. It's just our standard operating procedure to ask our veterinarians for their advice if we are not sure of things. So you do a little research, take them a few articles, and see what they have to say. Then you decide. Simple.
Regarding "lactose intolerance" we've yet to find a glider that has adverse reactions to small amounts of cheese or cottage cheese, but we do not feed it in large quantities. Not sure where the rumor of "lactose intolerance" came from anyway. I think that's more internet suggie lore than anything else. Considering how long they nurse both in-pouch and out, it is not very logical to think milk byproducts (yeah - suggies are not cows) would hurt them.
Ditto citrus or tomatoes. Don't know where the advice came from to steer clear of those either. We use orange juice as part of the LGRS suggie soup and that recipe has been successful in nursing a lot of sick gliders back to health over the years. Cherry tomatoes are a favorite of most of the rescues. They get them along with other foods once or twice a week alongside the soup. But we rotate all different fruits, veggies, yogurt, cheese and meats as side dishes with great variety.
Truly the best advice we can offer is to present diets, along with their published nutritional analysis, to your vet - or to even several vets - to get their opinions. Then decide.