What’s the Deal with Grapes?
Disclaimer: The following is merely surmised from my professional knowledge and opinion on grape toxicity in the field of veterinary medicine, and not my fealty to the Kritzman family creed:
“No raisin shall reside in a baked good where a chocolate chip may be instead.”
The cookie trays and Grandma Sally’s dessert grab bag at the Kritzman family Chanukah party have been a time-honored tradition since before I was born. Now, as a mother myself, I help make the dozen different types of cookies that are needed to provide dessert to the Kritzman clan.
But there is one ingredient I will not bake with in my home, and that’s raisins. We almost never have grapes in the house either. Not because of the Kritzman creed, but because of my dog Emmie. She is our little hoover. As much as I appreciate her cleaning up after my two-year-old’s attempts to make her own taco with shredded cheese, Emmie will not hesitate to eat a grape or raisin if she gets the opportunity.
What’s the big deal about dogs and grape ingestion? Why are they toxic? For much of my career, the veterinary community didn’t really know. We were taught that grapes could be toxic, and even one could put a dog in kidney failure, but we don’t know which dogs or type of grape would cause this.
This lack of knowledge made me loathe grape toxicity as an emergency veterinarian. Not only because of the potential harm it could cause my patients, but it made me feel like a fearmonger to my clients. I had to give people the worst-case scenario for something that might never happen. Although for most dogs the ingestion of one grape won’t cause any problems, for some dogs it could be fatal. And we didn’t know why.
Today, we have more insight. Starting in 2022, tartaric acid (cream of tartar, for us bakers) was seen to cause the same type of kidney damage in dogs as caused by grape toxicity. The problem usually manifests as lethargy, vomiting, diarrhea, and an increase in thirst initially.
Grapes contain tartaric acid, but the concentration of tartaric acid varies wildly between grape varietals and how ripe they are, which makes it quite difficult to calculate an ingested dose. This is why any grape ingestion can be of concern.
So grape toxicity is not a myth or means to rack up the bill at an emergency clinic. If your dog only gets one grape or raisin, you may be in the clear, but you should still reach out to your veterinarian to determine if medical care is needed.
If you’re like me and live with your dog and two semi-feral racoons (a.k.a., small children), you may find it’s just safest to keep grapes and raisins out of the house. Which is not a grave sacrifice for me (see family creed above). I will happily go about baking with chocolate chips, for which I can easily calculate the amount my dog will need to ingest to result in any problems (3 ounces of semi-sweet chocolate). But that is for another blog.
Happy holidays to you all, and best of luck with all the baking!
—Dr. Alyssa Kritzman