How to read cat and dog food labels: ingredients, preservatives and dangerous foods

Check the type of food first: complete or complementary?

One of the most important pieces of information on the label is whether the food is a complete feed or a complementary feed. A complete feed is formulated to meet the animal's daily nutritional needs when fed on its own. A complementary feed (treats, some wet foods, snacks), on the other hand, is not sufficient on its own and should be given together with other foods.

Also check which age and life stage the food is suitable for (kitten or puppy, adult, senior, neutered). Young animals have different energy, protein and mineral needs while they are growing. In Türkiye, pet foods are regulated under feed legislation and inspected by the Ministry of Agriculture and Forestry, and the labelling rules are largely aligned with the EU.

The ingredient list: watch the first few places

Pet food ingredients are also usually listed from most to least by weight. Cats are obligate carnivores, and dogs are omnivores with a strong leaning towards meat; so in a good-quality food you would generally expect a named animal protein source (such as chicken, lamb or salmon) at the top of the list.

There is a subtlety here: fresh meat contains a lot of water. Even if “fresh chicken” is at the top of the list, it loses much of its weight after cooking and drying. By contrast, “dried chicken protein” or “chicken meal” is a concentrated protein source with the water removed. So as well as the first ingredient, you also need to look at which protein and grain sources come after it.

The wording of the product name also tells you something: names such as “chicken”, “with chicken” and “chicken flavour” correspond to different minimum amounts. Under the European pet food industry's labelling rules (FEDIAF), a product named simply “chicken” means at least 26% chicken, “rich in chicken” at least 14% and “with chicken” at least 4%. “Flavour”, meanwhile, shows that the ingredient is below 4%, and the taste and smell may even be provided only by a flavouring. If the percentage of the ingredient is stated, that figure is the clearest information.

By-products: something to fear?

The phrases “animal by-products” or “meat and animal derivatives” worry many people. These terms can cover offal that is not commonly eaten by people but can be nutritious (such as liver, kidney and heart) and other animal parts. In nature, carnivores also eat the organs of their prey; these organs are rich in vitamins and minerals.

The real problem is that these phrases are general and vague: it is not always clear which animal and which parts they come from. Phrases that name the source (“chicken liver”, “lamb meat”) are more transparent. This transparency also matters for animals allergic to a particular protein, because general phrases can include different animal species.

Preservatives and other additives

• Natural antioxidants: Mixed tocopherols (vitamin E) and rosemary extract are often used to stop the fats in pet food going rancid, and they are of low concern. Foods made with these preservatives may have a shorter shelf life.
• Synthetic antioxidants: BHA and BHT effectively prevent fats from spoiling and are used within permitted limits. BHA is classified by IARC in Group 2B (possibly carcinogenic to humans; limited evidence), so some owners prefer foods without these substances.
• Propylene glycol: It can be used as a humectant in wet and semi-moist foods. It is accepted within permitted limits for dogs, but it is not suitable for cats. Because it can cause changes in red blood cells in cats (Heinz body formation), its authorisation as an additive in cat feed was withdrawn in the EU in 1991, and in the US the FDA has also banned its use in cat food. In our app this substance is rated in a wide, high range in the pet category; the upper end reflects cat food.
• Colours and sugar: Colours such as caramel colour are there to make the food look appealing to the owner; colour does not matter to cats and dogs. Sweeteners such as sugar and syrup are not nutritionally necessary either.
• Thickeners: In wet foods, ingredients such as carrageenan or guar gum create a jelly or gravy texture. For animals with a sensitive digestive system, this can be discussed with a vet.

The analytical constituents table

The label shows crude protein, crude fat, crude fibre, crude ash and moisture as percentages. These values help you understand the food's nutritional profile. Be careful when comparing dry and wet foods: because wet foods contain a very high proportion of moisture, their protein percentage looks low. For an accurate comparison, the values need to be converted to a “dry matter” basis, that is, calculated on what remains after the moisture is removed.

In cat food, it is important to see that nutrients essential for cats, such as taurine, have been added. Cats cannot make enough taurine themselves; a deficiency can lead to heart and eye problems. This is why dog food should not be given to cats on a regular basis.

Foods you should not give your pet

As well as the pet food label, food given from the table is an important source of risk. Some human foods can cause serious poisoning in cats and dogs:

• Xylitol: This sweetener, found in sugar-free gum, sugar-free sweets, some peanut butters and toothpastes, can cause a dangerous drop in blood sugar and liver damage in dogs. Keep products labelled xylitol or E967 away from dogs.
• Grapes and raisins: These can cause kidney failure in dogs; because the amount that causes harm varies from dog to dog, no safe amount has been established.
• Onion, garlic, leeks: Raw, cooked or powdered, they can damage red blood cells. They are risky for both cats and dogs; this includes ready meals that contain onion powder.
• Chocolate and caffeine: Because of the theobromine and caffeine they contain, dark chocolate in particular is dangerous for dogs.
• Alcohol and raw yeast dough: These can cause serious poisoning.

If you suspect your pet has eaten one of these foods, contact your vet immediately without waiting for symptoms to appear. Do not try to make your pet vomit yourself; only do so if your vet tells you to.

A quick checklist for choosing pet food

• Is it a complete or a complementary feed?
• Is it suitable for your pet's age and life stage?
• Is there a named animal protein near the top of the list?
• If it is cat food, is it free of propylene glycol and has taurine been added?
• Does it contain unnecessary colours and sugar?
• Does the recommended daily amount suit your pet's weight and activity level?

In special situations such as kidney or urinary tract problems, allergies or weight issues, it is best to choose food together with your vet. For general principles of label reading, see also our ingredient list order guide.