Human Foods Your Dog Can’t Eat | Our Expert Guide

By Bethany Barley
5 min read
A dog lying on grass

Sharing a bite from your plate can feel harmless. A corner of toast, a little cheese, a dropped grape from a child’s lunchbox. Yet some everyday human foods do not agree with dogs and may lead to digestive upset or other health problems if fed regularly or in the wrong amounts. So, which foods should dogs not eat? Here’s a practical guide to the main foods to avoid, along with a few that need extra care.

Key takeaways

  • Dogs should never eat chocolate, grapes and raisins, onions, garlic, macadamia nuts, xylitol, alcohol or raw yeast dough.
  • White chocolate, milk chocolate and baking chocolate all carry risk, with darker chocolate usually more dangerous.
  • Some foods are not toxic to dogs but still unsuitable in a large amount, including cheese, salty foods, and tuna.
  • Puppies need extra care because their stomachs are still developing.
  • When unsure, stick to a complete, balanced dog diet such as Burns dog food.

Foods dogs should never eat

Chocolate

Chocolate contains methylxanthines, which dogs process poorly. Baking chocolate and dark chocolate are especially concerning, but milk chocolate and white chocolate should also be avoided. Signs can include restlessness, tremors, vomiting, diarrhoea, and even heart problems. Call your vet promptly if your dog eats chocolate.

Grapes and raisins

Grapes and raisins can be dangerous even in small amounts. They have been linked with sudden kidney failure, and there is no reliable “safe” amount. Keep fruit bowls, lunchboxes and hot cross buns out of reach. Blue Cross warns that even a small amount may make some dogs seriously ill.

Onions, garlic, leeks and chives

These foods can damage a dog’s red blood cells, which may lead to anaemia. The risk applies to raw, cooked, powdered and dried forms. That matters because onion and garlic are often hidden in gravy, stuffing, sauces and leftovers.

Macadamia nuts

Macadamia nuts are toxic to dogs and may cause weakness, tremors, vomiting and discomfort. Other nuts can be fatty or salted, so they are rarely a sensible treat.

Yeast dough and alcohol

Raw yeast dough can expand in the stomach and produce alcohol as it ferments. Alcohol itself is unsafe for dogs and can cause serious poisoning. Keep rising dough well away from curious noses.

Foods to avoid or treat with real caution

Avocado

Avocados contain persin, which can be harmful to some animals. The flesh is also fatty, and the stone is a choking or blockage risk. Simple answer: avoid it.

Peppers

Plain sweet peppers may be tolerated by some dogs in small amounts, but chilli and spicy peppers are unsafe. Spices can irritate the digestive system and cause unnecessary distress.

Tuna

Should dogs eat tuna? Not regularly. Tuna is not classed as toxic, but it can contain mercury, so it should not become a routine food. A tiny amount of plain tuna may be fine for some adult dogs, yet a complete dog food is a safer daily choice.

Tomatoes

Ripe tomato flesh in small amounts is usually tolerated, but green tomatoes, stems and leaves contain compounds that are toxic to dogs. Avoid letting dogs chew tomato plants in the garden.

Peanuts

Peanuts must be plain, unsalted and free from sweeteners. Some peanut butters contain xylitol, which is highly dangerous for dogs. Always check the label.

Popcorn, bread, toast and rye bread

Plain popcorn is low risk in small amounts, but butter, salt and flavourings are not. Bread, toast and rye bread are usually safe if plain, but they add little nutrition. Avoid raisins, seeds, garlic, onion or sweet spreads.

Cheese and dairy

Cheese is popular with many dogs, but milk and dairy can upset dogs that are lactose intolerant. Keep portions small, and avoid rich or blue cheeses.

Garden plants and flowers

Sometimes, dogs will chew grass, leaves, flowers or fallen bulbs while exploring the garden. While daisies are not usually highly toxic to dogs, they can cause stomach upset if eaten. Other common garden plants, including daffodils, tulips, foxgloves and bluebells, can be more harmful. If your dog has chewed a plant and starts to seem unwell, contact your vet for advice.

Other human foods dogs should avoid

Some foods are less commonly discussed but can still cause problems for dogs, especially in small amounts or if eaten regularly.

  • Xylitol: Found in sugar-free gum, sweets, peanut butter and baked goods. Extremely toxic to dogs and can cause a dangerous drop in blood sugar and liver failure.
  • Caffeine: Coffee, tea, energy drinks and caffeine tablets can overstimulate the heart and nervous system.
  • Raw potato and green potato skins: Contain solanine, which is toxic to dogs.
  • Corn on the cob: The cob itself can cause a serious intestinal blockage.
  • Ice cream: Often high in sugar and dairy, which may upset dogs that are lactose intolerant.
  • Fatty leftovers and gravy: Rich foods may trigger vomiting, diarrhoea, or in some cases pancreatitis.
  • Fruit stones and apple seeds: Can present choking risks and contain compounds that are unsafe in large amounts.
  • Cat food: Not toxic, but too rich for regular feeding and not nutritionally balanced for dogs.
  • Raw meat and raw fish: May carry bacteria or parasites if not handled carefully.
  • Mushrooms: Store-bought mushrooms are usually lower risk, but wild mushrooms should always be avoided.
  • Nutmeg: Common in baked goods and can affect the nervous system in dogs.
  • Salty snacks: Crisps, processed meats, and heavily salted foods are unsuitable for dogs and may contribute to dehydration.

What to do if your dog eats something unsafe

English toy spaniel lying on the floor.

Stay calm, remove the food, and call your vet. Note what was eaten, how much, and when. Do not wait for symptoms after high-risk foods such as grapes and raisins, chocolate, xylitol, macadamia nuts or yeast dough. Dogs Trust advises contacting your vet immediately if ingestion is suspected.

For everyday feeding, a consistent, complete diet gives dogs the balanced nutrition they need day after day. Burns offers a wide range of dog food, including recipes for puppies, seniors, sensitive stomachs and weight control, all carefully developed to support long-term health through simple, balanced nutrition.

FAQs

What foods are most toxic to dogs?

Chocolate, grapes and raisins, onions, garlic, xylitol, macadamia nuts, alcohol and raw yeast dough are among the main foods dogs should never eat.

Can dogs eat raw eggs?

Raw eggs are not recommended due to the risk and possible digestive upset. Cooked plain egg may suit some dogs in small amounts, but it should not replace balanced food.

Are salty foods bad for dogs?

Yes. A large amount of salt can cause excessive thirst, vomiting, diarrhoea, tremors and more serious symptoms. Avoid crisps, salted popcorn and heavily seasoned leftovers.

Conclusion

The safest rule is simple: check before sharing. Some natural, healthy-looking foods are toxic to dogs, while others are only suitable in small amounts or when prepared plainly. Clear boundaries are not unkind. They help protect your dog from avoidable stomach upsets, toxic reactions, and long-term harm. For daily feeding, keep it steady, balanced, and dog-specific.