A Guide to Choosing a Diet for your Pet

Petfix Club
26th January 2021 - 5 min read

One of the most important decisions to make when you own a pet is what to feed them. The huge and bewildering range of brands and products in pet stores, at supermarkets, and at vet clinics only makes the decision more difficult.

Our aim is to try to make it easier for people to understand the science (or absence of science) behind the pet food that’s available in the market place.

man hand feeding dog

The Importance of a Balanced Diet

Academic nutritionists know, after many decades of research, what animals need to eat to keep them healthy throughout their lives. Vet students are taught all about nutrition at vet school, for dogs and cats as much as for farm animals: the same principles of a balanced diet apply across all species.

The foods that must be fed in the correct quantities and proportions are:

  • Protein
  • Fat
  • Carbohydrate
  • Fibre
  • Vitamins
  • Minerals

Pets that are fed on high quality, complete diets (like the Petfix Club range) tend to:

  • Look healthier – with a brighter eye and a glossier coat.
  • Their internal systems are also likely to be healthier with higher quality nutrition.


Pet food manufacturers create their products following the guidelines and advice of national and international scientific advisors, so that they can fulfil the brief of guaranteeing that pets stay healthy when fed their products over many months and years.

It’s worth taking the time to read the label of a pet food container, to gain extra information about exactly what has gone into the food that you’re feeding your pet.

Choose brands of food that list ingredients on the label that you can understand, rather than vague, catch-all terms. Look for ingredients like chicken meal, lamb meal, corn or maize: these are examples but there are many others.

Complete Vs Complementary Foods

The labelling of pet foods is highly regulated: if a product is labelled as “complete”, it must, by law, provide all of the nutrients a pet needs. Most pet dry kibble diets fit into this category. 

“Complementary” pet foods are different: they need to be fed alongside other products to ensure that a pet gets all the nutrients they need:  for example, mixer biscuits cannot be fed solely on their own; tinned or sachet meat needs to be fed with them for a pet to enjoy a complete and balanced diet.

puppies eating biscuits
Puppies eating “complementary” foods

Quality of Ingredients

Apart from the basic facts of “complete” and “complementary” foods, it’s important to consider the precise listed ingredients that are included in a recipe for commercial pet food.

Higher quality ingredients are more likely to create a product that is tastier and easier to digest. A lower grade of ingredients can still create “nutritionally complete” food, but the final product is more likely to be associated with more digestive upsets, more copious faeces, and an animal not thriving as well as they might do, with subtle signs of poor health such as:

  • A scurfy coat
  • Dull eyes
  • Less energy

How to Read a Pet Food Label

Reading a pet food label should be something that all owners do when choosing food for their pets. Ideally, avoid products if the first listed ingredient is named as ‘animal derivatives’: these pet foods are often lower in quality.

What are Derivatives?

The use of a catch-all term “derivative”, instead of a specific named ingredient like “chicken”, means that the manufacturer can include general off-cuts from a range of sources from the abattoir (perhaps including the cheapest and most available products) rather than paying a bit more for the same, specific meat ingredient in successive batches of the same product. If cheaper ingredients are used, the end product will often be less digestible, and less tasty.

It’s better, generally, to avoid “catch all” terms such as the following:

a) Derivatives of vegetable origin is a vague term used to describe by-products of vegetable origin. This can include anything that has been derived from a vegetable, and so it could be used to hide unspecified ingredients that a manufacturer may not wish you to know about.

b) Meat and animal derivatives can describe any meat or animal by-product, without being specific about what it is – or even what species it comes from. This enables the manufacturer to change the protein source with every batch without changing the label. It may be handier and cheaper for the manufacturer to be able to do this, but it may not be ideal for your pet.

c) EC permitted additives  include over 4000 chemical additives that can be added to pet food without individually naming them. The list includes colouring agents that have been proven to cause hyperactivity in children, and it seems logical that the same substances could have the same effect on some pets.

Low Quality Product

While some pets can thrive on a lower quality product (with derivatives), many dogs and cats can have digestive or health issues. A better quality pet food with specific, listed ingredients is more likely to be associated with a thriving, healthy pet.

To learn more, listen to our Podcast on How to Read and Understand Pet Food Labels

Specialized Diets

Choose a diet that has been designed for your particular pet: “puppy food” is designed to help pups grow, and so-called “senior” diets contain nutrition specially tailored to older pets. These specialized diets are more likely to provide nutrition that suits your individual pet.

puppy on top of dog on the grass

Feeding Amount

Most pets prefer to be fed twice daily, and it’s very important to get the quantity of food right. Obesity is the most common nutrition-related disease seen in pets. Use the instructions on the container as a guide to how much to give, but use common sense too.

Regular weighing of your pet is the best way to make sure you’re feeding the right amount. Most vet clinics have walk-on scales that make it easy to do this, and there’s usually no charge for doing this.

If you’re not sure what to feed your pet, ask us at Petfix Club. We’ll be happy to help you make the right choice.