Ingredients your dog food should not contain: What to watch for on the label

Choosing dog food can feel deceptively simple. Pick a trusted brand, check the protein source and follow the feeding instructions, except the ingredient list can often tell you much more about what is actually going into your dog’s bowl. Not every unfamiliar ingredient is harmful, and some additives have legitimate purposes, such as preserving food or maintaining its texture. But veterinarians generally advise pet parents to pay attention to certain ingredients, particularly when they appear in large amounts or when a dog has a known sensitivity. Here are some ingredients and categories worth watching for when you read a dog-food label.

Dogs do not care whether their food is bright red, yellow or green. Artificial colours are primarily added to make food look more appealing to humans. While approved food colours are regulated for safety, they provide no nutritional benefit to dogs. If you’re choosing between otherwise similar products, a food without unnecessary artificial colouring is a sensible option.

Some foods use flavour enhancers to make kibble more appealing. While flavouring itself does not automatically make a product unsafe, heavily flavoured foods can make it harder for owners to assess the quality of the underlying ingredients. Look instead for foods where a clearly identified animal or plant protein is among the principal ingredients.

Preservatives are important in commercial pet food because they prevent spoilage and help maintain freshness. However, pet parents may prefer products that use established preservatives at permitted levels rather than foods containing a long list of unnecessary additives. Common preservatives you may encounter include BHA, BHT and ethoxyquin. Their safety has been assessed by regulatory authorities at permitted levels, so their presence does not automatically mean a food is dangerous. Still, owners looking to minimise unnecessary additives can compare products and choose alternatives where appropriate.

Dogs don’t need added sugar in their diet. Ingredients such as sucrose, glucose syrup, molasses or other sweeteners can add calories without providing meaningful nutritional value. Regularly feeding calorie-dense foods can contribute to excessive weight gain, particularly in dogs that already get treats throughout the day. Sugar is therefore an ingredient worth avoiding when it serves no nutritional purpose.

Sodium is an essential nutrient for dogs, so salt itself isn’t poisonous in the small amounts normally present in complete dog food. The concern is excessive sodium, particularly when a dog is also receiving salty human foods or treats. Dogs with certain medical conditions may also require dietary sodium restrictions, but those decisions should be made with a veterinarian.

This is one category that deserves particular attention. Onions, garlic, leeks and chives belong to the Allium family and can be toxic to dogs. They can damage red blood cells and, in sufficient quantities, cause anaemia. They may appear in some human foods, sauces, broths and seasoning mixes, making it important not to assume that a food is safe simply because the amount looks small.

Xylitol is particularly dangerous for dogs. It is a sugar substitute found in some sugar-free products and can cause a rapid drop in blood sugar and potentially serious liver injury. It is more commonly encountered in human foods, toothpaste and other products than in mainstream dog food, but pet owners should always check labels before sharing human treats with their dogs.

Perhaps the most important point is that an ingredient list should be considered as a whole. An unfamiliar chemical-sounding name doesn’t necessarily mean an ingredient is dangerous, just as a short ingredient list doesn’t automatically make a food nutritionally complete. Commercial dog foods should be formulated to meet dogs’ nutritional requirements, and the nutritional adequacy statement is often more useful than simply counting ingredients.

For dogs with allergies, kidney disease, obesity, diabetes or other health problems, the right diet can be very different from the general recommendation. The best approach is to choose a complete and balanced food appropriate for your dog’s age and life stage, avoid foods containing known toxic ingredients, and speak to a veterinarian before making major dietary changes.