Safe Around Pets

What UK pet owners get wrong about food safety

Most pet poisonings aren’t caused by owners being careless. They’re caused by owners being confident about the wrong things. Here are 13 of the most common myths, corrected in plain English and ordered by how dangerous they are.

  1. 1. “A little chocolate won’t hurt

    The truth: There is no safe dose. Theobromine, the toxic compound in chocolate, accumulates in a dog’s system, and dark chocolate can be fatal in amounts as small as 20g for a medium-sized dog. The PDSA advises that any amount warrants an urgent call to your vet.

    Why it matters: “Just a square” is one of the most common reasoning patterns behind accidental poisonings.

    Read more:Chocolate

  2. 2. “Grapes are fine, it’s raisins you have to worry about

    The truth: Grapes are equally dangerous. Raisins are concentrated grapes, and the toxin responsible for acute kidney failure is present in both. Even a single grape has caused kidney failure in some dogs. Blue Cross advises treating any grape or raisin ingestion as an emergency.

    Why it matters: Many owners restrict raisins but hand grapes to dogs as a “healthy snack” without a second thought.

    Read more:GrapesRaisins

  3. 3. “Onions are only dangerous in large amounts

    The truth: All alliums (onions, garlic, leeks, chives) are toxic to both dogs and cats at any meaningful dose. The threshold is around 0.5% of body weight for onions, and damage accumulates with repeated small exposures. Garlic powder is far more concentrated than fresh garlic.

    Why it matters: Owners often dismiss small amounts, or don’t realise garlic powder in cooking is much more concentrated than fresh garlic.

    Read more:OnionsGarlic

  4. 4. “Xylitol is only in sweets, so my dog’s fine if he ate a biscuit

    The truth: Xylitol turns up in far more products than most owners realise: certain peanut butter brands, chewing gum, sugar-free baked goods, some vitamins, and mouthwash. It causes a rapid, severe insulin release in dogs that can be fatal within hours. Blue Cross advises checking the label of any sugar-free product before letting your dog near it.

    Why it matters: Owners associate xylitol with confectionery and miss it in unexpected sources. “Sugar-free” on a label should trigger immediate label-checking.

    Read more:Xylitol

  5. 5. “Cooked bones are safer than raw

    The truth: Cooking makes bones brittle. They splinter into sharp shards that can perforate the oesophagus, stomach, or intestines, which is a genuine surgical emergency. Raw bones carry their own risks but are significantly less likely to shatter. The PDSA advises avoiding cooked bones entirely, including those from roast dinners and leftover joints.

    Why it matters: “I cooked it, so it must be safer” is intuitive but backwards here. Many dogs are hospitalised after a roast dinner leftover.

  6. 6. “Milk is good for cats

    The truth: Most adult cats are lactose intolerant. Kittens produce lactase to digest mother’s milk, but most lose this ability after weaning. Cats Protection notes the milk-loving cat is largely a cultural myth. Cow’s milk typically causes stomach upset and diarrhoea.

    Why it matters: It’s one of the most persistent domestic pet myths, passed down across generations and reinforced by old cartoons.

    Read more:Milk

  7. 7. “Dogs can eat any fruit, it’s natural

    The truth: Several fruits are outright toxic to dogs: grapes and raisins (kidney failure), cherries (cyanide in stones and leaves), and stone fruits like plums and peaches. Even “safe” fruits like apples should have the seeds removed first.

    Why it matters: “Natural = safe” is a common heuristic that doesn’t apply to dogs. Their metabolisms differ significantly from ours.

    Read more:GrapesApples

  8. 8. “Garlic is good for dogs, it keeps fleas away

    The truth: Garlic is toxic to dogs. It belongs to the allium family and causes oxidative damage to red blood cells, leading to haemolytic anaemia. The “garlic repels fleas” claim has no veterinary evidence behind it.

    Why it matters: This myth actively circulates in natural pet care communities. Some owners deliberately add garlic to their dog’s food.

    Read more:Garlic

  9. 9. “Avocado is only dangerous to birds

    The truth: Avocado contains persin, which is toxic to dogs and cats as well as birds, rabbits, and horses. The flesh is the primary concern for dogs and cats. The stone is also a choking and obstruction hazard.

    Why it matters: Many owners have seen the “toxic to birds” warning and concluded dogs are safe. Trendy human foods like guacamole bring this risk into more kitchens.

    Read more:Avocado

  10. 10. “Dogs love macadamia nuts, they’re a safe treat

    The truth: Macadamia nuts are toxic to dogs. Even small amounts can cause weakness, hyperthermia, vomiting, and tremors within 12 hours. The specific toxin hasn’t been identified, but the reaction is well-documented.

    Why it matters: Macadamias are expensive and perceived as a premium, wholesome food. Owners may share them as a special treat.

    Read more:Macadamia nuts

  11. 11. “Raw salmon is fine, dogs eat fish in the wild

    The truth: Raw salmon isn’t reliably safe. Certain Pacific salmon can carry the parasite responsible for Salmon Poisoning Disease in dogs, which is uncommon in the UK but reported. The parasite is destroyed by cooking or freezing.

    Why it matters: The raw feeding movement has increased exposure to raw fish, an under-discussed risk compared to chocolate or grapes.

    Read more:Cooked salmon

  12. 12. “Cats can eat dog food in a pinch

    The truth: Dog food isn’t nutritionally adequate for cats. Cats are obligate carnivores and need taurine, arachidonic acid, and vitamin A in amounts dog food doesn’t provide. An occasional bite won’t harm them, but it shouldn’t become a habit.

    Why it matters: Multi-pet households often assume food is interchangeable, a lower-stakes myth but a common one worth addressing.

  13. 13. “Bread dough is harmless, it’s just flour and yeast

    The truth: Raw bread dough is dangerous. Yeast keeps fermenting in a dog’s warm stomach, producing carbon dioxide (painful bloating) and alcohol (ethanol toxicity). Both can be life-threatening, so treat it as an emergency.

    Why it matters: Baking at home is on the rise. Owners may not think twice about dough scraps or a bowl left to prove on the counter.

Every food on this site has its own page, checked against the latest veterinary guidance. If you're ever in doubt, call a vet. Don't wait for symptoms.

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