By Dial A Vet Veterinary Team
Breakfast is a busy time, and a cat on the bench can be into the cereal bowl before you notice. If your cat has had a few flakes of plain cereal, it is very unlikely to be a problem. What matters most is what kind of cereal it was. Chocolate cereals, muesli with raisins or nuts, and the milk in the bowl all deserve a closer look.
Key takeaways
- A few pieces of plain cereal are unlikely to harm a cat, but cereal gives cats nothing they need.
- Chocolate-flavoured cereals typically contain cocoa, which is toxic to pets.
- Raisins in muesli or bran cereals are a known danger to dogs. Evidence in cats is limited, but vets usually treat cat ingestions with similar caution.
- Milk often upsets cats' stomachs, because pets have little of the enzyme that breaks down lactose.
- Recipes vary between brands and countries, so check the label of the box you have.
- Related reading: can cats eat chocolate, can cats eat raisins.
Why cereal is not a good food for cats
Most breakfast cereals are made from grains such as oats, wheat, corn or rice, with added sugar, salt and vitamins. As an example, General Mills lists US Original Cheerios as whole grain oats, corn starch, sugar, salt and tripotassium phosphate, plus added vitamins and minerals.
RSPCA Australia explains that cats are obligate carnivores and do not have some of the enzymes and body processes other animals use to digest and convert plant nutrients. Cereal fills a small stomach without supplying the animal protein and nutrients a cat needs. Research published in PLoS Genetics also found cats lack a working sweet taste receptor, so the sugar in sweetened cereals does nothing for them beyond adding calories.
Ingredients to check
Chocolate and cocoa. The ASPCA lists chocolate as a danger to pets because of methylxanthines, which can cause vomiting, diarrhoea, excessive thirst, hyperactivity, an abnormal heart rhythm, tremors and seizures. A few pieces of chocolate cereal usually contain much less than a chocolate bar, but call for advice if your cat ate a noticeable amount.
Raisins and sultanas. Grapes and raisins can cause kidney failure in dogs. The Pet Poison Helpline notes that dogs are the only species positively identified as sensitive so far, with a few anecdotal reports in cats, and that cat ingestions are typically treated like dog ingestions as a precaution. A 2022 study of poison centre cases found that of 13 cats that ate grapes or raisins, 2 developed signs (mainly vomiting) and none developed kidney injury. That is reassuring, but not proof of safety.
Nuts. The ASPCA notes that the fats in nuts can cause vomiting and diarrhoea, and potentially pancreatitis, in pets.
Sweeteners. The Pet Poison Helpline says there is currently no published data suggesting cats are sensitive to xylitol, and a small study in six healthy cats found no low blood sugar or liver changes. Dogs are a different story, so keep xylitol products away from any dogs in the home.
The milk in the bowl
The ASPCA explains that pets do not have significant amounts of lactase, so milk and dairy can cause diarrhoea or other digestive upset. Cornell's Feline Health Center agrees that milk is not generally recommended as a treat because many cats are lactose intolerant.
Signs to watch for
- Vomiting
- Diarrhoea or soft stools
- Bloating or gas
- Reduced appetite
After chocolate cereal, also watch for restlessness, panting, a racing heart or tremors. After raisins, watch for vomiting, reduced appetite, lethargy or changes in drinking and urination over the next few days.
When to call a vet or the Animal Poisons Helpline
For a few pieces of plain cereal, home monitoring is usually enough.
Call your vet or the Animal Poisons Helpline (1300 869 738) if your cat ate chocolate cereal, cereal or muesli containing raisins or sultanas, or a large amount of any cereal.
Call your vet if vomiting or diarrhoea lasts more than a day, if your cat stops eating, or if your cat has diabetes or kidney disease.
Seek urgent care for tremors, seizures, collapse or a very fast heart rate.
How vets help
Your vet will ask what was eaten, how much and when. For plain cereal, advice is usually all that is needed. For chocolate or raisins, they will assess the risk for your cat's size and may recommend treatment such as making your cat vomit in the clinic, fluids or blood tests.
Better breakfast company
- Feed your cat its own breakfast at the same time as yours
- Offer a commercial cat treat
- Keep cereal boxes and bowls off the bench and out of reach
Cornell suggests treats make up no more than 10 to 15 percent of a cat's daily calories.
FAQ
My cat ate a few cornflakes. Is that okay?
Yes, a few plain flakes are unlikely to cause any problem.
Can cats eat oats?
Plain oats are not toxic, but cats do not need them. Talk to your vet before adding grains to your cat's diet.
What if my cat ate muesli with raisins?
Call your vet or the Animal Poisons Helpline. Evidence in cats is limited, so vets usually take a cautious approach.
Is lactose-free milk okay?
It is less likely to cause diarrhoea, but it is still not a necessary part of a cat's diet. Water is the best drink.
Talk with a vet
If your cat got into a bowl of flavoured cereal or muesli, a Dial A Vet veterinarian can help you decide whether a clinic visit is needed. Book a Dial A Vet consult.
References
- General Mills. Original Cheerios | Gluten Free Multi Grain Cereal.
- RSPCA Knowledgebase. What should I feed my cat?.
- Li X, et al. PLoS Genet. 2005;1(1):e3. Pseudogenization of a Sweet-Receptor Gene Accounts for Cats' Indifference toward Sugar.
- ASPCA Animal Poison Control. People Foods to Avoid Feeding Your Pets.
- Pet Poison Helpline. Feline Safety.
- Dijkman MA, et al. J Small Anim Pract. 2022;63(6):447-453. Incidence of Vitis fruit-induced clinical signs and acute kidney injury in dogs and cats.
- Jerzsele Á, et al. J Vet Pharmacol Ther. 2018;41(3):409-414. Effects of p.o. administered xylitol in cats.
- Cornell Feline Health Center. Feeding Your Cat.
- Animal Poisons Helpline (Australia, 1300 869 738). Animal Poisons Helpline | 24/7 Pet Poisoning Advice.
Disclaimer: Educational only. This page does not replace an examination or advice from your own veterinarian. If you are worried about your pet right now, contact your local vet or nearest emergency animal hospital.