Here's what the ASPCA has to say:
I’ve heard that grapes and raisins are poisonous to dogs. Yes or no?
- Sheila C.
Yes, Sheila. At the current time, we know that grapes and raisins appear to cause renal failure in dogs who’ve ingested large amounts. However, we have not determined with certainty the toxic component, or the exact mechanism that causes renal failure. It is also not clear if only certain dogs are affected, or if long-term ingestions can lead to the same effects that a large one-time ingestion can. Because there are still many unknowns regarding the toxic potential of grapes and raisins, it is advisable not to give grapes or raisins to dogs in any amount.
I understand that garlic is poisonous for dogs, but why is it often an ingredient in dog treats?
- Michelle S.
Good question, Michelle. Garlic does have toxic potential to pets, and is generally more potent than onion, also a member of the Allium species, in causing changes in red blood cells in dogs and cats. This is true in raw, cooked or powdered forms. In theory, "deodorized" garlic is allegedly less toxic, since the disulfides, responsible for both the odor and the toxicity, are usually largely removed.
Even at low levels of exposure to garlic, some change in red blood cells is likely; it is typically only when a significant number of red blood cells are altered that their oxygen-carrying capacity is noticeably compromised and clinical signs develop. Generally, it takes either a fairly large single ingestion or chronic exposure. These effects are also somewhat more likely to be seen in cats, as their red blood cells have shorter life spans and they're more likely to have bone marrow issues. However, the possibility exists that some dogs may also be genetically more susceptible to problems from garlic ingestions.
The lowest observed effect level in dogs in the scientific literature that we are aware of is 2.5 mg/kg of encapsulated garlic powder; slow heart rates and increased urination were seen. For comparison, a 20-pound dog consuming 1000 mg of garlic powder is exposed to a dose of 110 mg/kg.
The bottom line, Michelle, is that we do not definitively know at what dose any given dog may experience problems. An occasional low dose, such as those found in most commercial pet foods or treats, would not likely cause problems. A conservative approach might be to avoid exposure to more concentrated garlic-based products.
Thgere's big list of different foods here:
http://www.aspca.org/pet-care/ask-the-expert/ask- ... foods.aspx
I looked through some of them and most listed mild issues. Popcorn for example was a choking hazard. I would think blockages would be an issue too if you fed them too much popcorn? My dog eats it, great food for "catch"