How diet can affect your dog

Written by Pure Pet FoodPure Pet Food are the experts in healthy dog food and healthy dogs featured in media outlets such as BBC, Good Housekeeping and The Telegraph. Working with high profile veterinary professionals and nutritionists, Pure Pet Food are changing dog food for the better. Dr Andrew Miller MRCVSDr Andrew Miller MRCVS is an expert veterinary working in the field for over 10 years after graduating from Bristol University. Andy fact checks and writes for Pure Pet Food while also working as a full time veterinarian. - Our editorial process

There was a time when we didn’t put much thought into what we fed our dogs, most of us just picked up a bag or tin of dog food from our local pet shop, naively thinking (as it turns out) that anything labelled as dog food contained a healthy, natural and balanced diet that’s best for our pooches.

Nowadays just as we give much more thought to the types of food that make up our own diets, more and more of us are paying attention to how the food we feed is made and what kind of ingredients are in the food that our four-legged friends are eating, which is brilliant.

Making the appropriate dietary choices for your dog is so important, as is ensuring that he is adequately hydrated.

This is because your dog’s diet affects his health, happiness and his behaviour. So many issues that affect some pooches such as itchy skin, loose stools and lethargy might be eliminated entirely by simply feeding them a more natural diet containing ingredients that actually benefit them.

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Let’s take a look at some of the things you might want to consider when choosing a dog food and how your pooches’ diet can have a profound effect on his wellbeing.

How food affects your dog

If you have ever gone through a phase of eating lots of processed convenience or fast foods or lived on tea and toast, you’ll remember only too well how it made you feel, lethargic, sometimes bloated and maybe even a bit irritable.

When you eat a natural, healthy diet that isn’t processed, like meats, nuts, fruit and veg, I bet you feel like a different person, full of life and ready to take on the world.

Food affects your mood and energy levels and guess what, dogs are the same!

Hyperactivity, for instance, has been linked to feeding low-quality, processed dog food (like brown biscuits) containing a disproportionate amount of carbohydrates like wheat as they cause a spike in a dog’s blood sugar levels.

If you’re feeding a food that isn’t very digestible like a processed brown biscuit, your dog may need to eat more than otherwise necessary which will lead to obesity. Obesity is a huge influence in the length of your dog’s life and how often they need to visit the vet.

{% quote "andy", "Nutrition is the foundation for our pets' well-being, feeding natural diets with simple ingredients ensures optimal health. We are what we eat so it shouldn't be different for our pets", "Dr. Andrew Miller MRCVS]

Dogs, like humans, can also be allergic to certain foods and react badly to them. Typically dogs’ could react with a sensitive stomach, sensitive skin and similar ailments.

Poor quality food (think highly processed and poor quality ingredients) can exacerbate these ailments or even bring these on without an allergen.

A dull coat changing into a glossy coat is one of the biggest changes you can see in your dog when switching food.

Pet food ingredients - What to look out for

With dog food marketers bombarding us with brightly coloured bags and trays with pictures of cute happy dogs on and claims such as Holistic or Happy Dog emblazoned on the packets it’s little wonder that many of us subconsciously decide on a dog food based on the branding alone. After all, first impressions count.

Think about your own shopping habits in the supermarket, I know I can’t be the only one who’s picked up a product based solely on the healthy-looking images only to realise when I get home that what I’ve actually bought is a packet of junk food. The very same mistake can easily be made with dog food, so studying the ingredients is essential.

Here are some pointers of what to take note of – don’t forget your magnifying glass!

1. Protein content – the optimum % of protein for the average dog, should be around 20%-30% any food containing less than 15% is too low.

2. A dog food containing fresh muscle meat is infinitely preferable to one containing meat meal or rendered meat, commonly referred to on dog food packets as “dried”. For example, if a pack proclaims 30% chicken, it is muscle meat, but if it says 30% dried chicken it is chicken that has usually been processed at very high temperatures prior to the food being produced.

Be careful though, this doesn’t include air-dried recipes such as Pure, air-dried recipes don’t use the same drying techniques and will use the term chicken or chicken breast and thigh.

3. Grain-free food is becoming more popular these days, as many highly processed dog foods (brown biscuit dog foods) use grains as fillers such as wheat and barley.

Of course, grains are not harmful to most dogs, but some can suffer from grain intolerance.

Some news sources have run headlines in the past that grain-free dog food causes heart disease and dilated cardiomyopathy (DCM) in dogs. However, the report (not study) did not show a true association, and veterinary professionals have dismissed this citing a need for more evidence.

4. Some dog foods contain ingredients that are not universally accepted as being safe for dogs to consume, although they are arguably safe in the micro amounts used in dog food such as garlic. The way I see it is why take the chance when there are plenty of alternatives that do not contain these.

5. Some forward-thinking dog food manufacturers, such as Pure, are now using only human-grade ingredients in their food. If you think about it, why would you feed your best friend something you wouldn’t eat yourself?

One thing to keep in mind when looking at ingredients is the processing that these ingredients go through to get in your dog’s food.

How does the manufacturing process affect dog food?

Different dog foods are made in different ways, we’ll talk through the differences in brown biscuits, tinned, raw, homemade, and air dried.

We’ll start with brown biscuits. These are made through extrusion. Extrusion is the process of adding ingredients (often poor quality, but not always) into a chamber which heats them to extreme temperatures then puts the ingredients through extreme pressure. Finally, they push this substance through a small hole and a machine will cut the pieces to size. Overall this is quite a destructive process which means many manufacturers will add nutrients back into the food artificially.

Homemade slowly cooks your dog’s food at a lower temperature to ensure that the nutrients are retained and is the same quality of food you’d find in your own food. It’s a great way of feeding your dog if you can deal with the hassle of making the food yourself or having a ton of freezer space.

Air dried is my favourite, it uses the lowest temperatures when air drying the food to lock in the goodness and ensure the nutrients are retained in the food as naturally as possible. The unobtrusive way of preparing your dog food makes it super convenient for an owner too because it doesn’t require any storage space and you simply just add water and stir for 30 seconds then it’s ready.

What are superfoods?

Most of us have started to add some superfoods to our diet, these nutrient-dense foods pack in more vitamins, minerals and antioxidants in every bite and thus help optimise our body’s ability to function.

Of course, no one superfood is a miracle worker, but a dog’s diet can be significantly enhanced if they are fed a nutritious natural diet that includes some canine-appropriate superfoods.

Parsnips, for instance, are a great source of Vitamin C which promotes healthy bones and teeth. They are also a great source of fibre and antioxidants. The humble cabbage contains Vitamin A and D. Apples also provide fibre and antioxidants. Coconut is brilliant for your pooches’ skin and coat as it contains vitamins E and K as well as iron.

Of course, these superfoods need to be fed to your pooch as part of an all-round balanced diet, but why not choose a dog food that includes some, your dog will benefit and have that bit more bounce – just like you experienced when you started to add them to yours!

What shouldn't a dog eat?

There are some foods that us humans have no problem in digesting that are incredibly toxic to dogs. These include but are not limited to onions, garlic, chocolate, grapes, raisins and others such as fatty table scraps and sweet biscuits that can cause all sorts of problems.

A diet high in fat, low in protein and bulked out by fillers such as wheat that have no or little benefits to your dog and/or includes preservatives is also best avoided. In fact, such a diet can cause your pooch to feel pretty uncomfortable and may create things like itchy skin and tummy upsets.

I go by the maxim that if I wouldn’t eat the ingredients in a dog food (albeit in a different form!) myself, I wouldn’t feed it to my dog.

What's the risk of an unbalanced diet?

Dogs that are receiving an unbalanced diet are prone to all sorts of issues including life-shortening obesity, bad breath, a dull coat, skin disorders, excessive shedding and an increased propensity to allergies. Inadequate nutrition can also be causal in several diseases such as pancreatitis and kidney disease.

Remember an unbalanced diet can contain too much of something as well as too little, so unless you are prepared to put in a lot of research, it’s definitely safer and more convenient to look out for a healthy, premium, commercially produced dog food that is not highly processed (like brown biscuits) than to feed from scratch yourself.

How to feed your dog

Mealtimes are one of the highlights of the day for most pooches, and I expect lots of us have witnessed the relentless pacing up and down as the time approaches food o’clock, the doleful eyed stare or the dinner dance.

Many dogs prefer to eat their food from a regular dog bowl; however, some pooches gobble their food down too fast, putting them at risk of choking or bloat. If yours is one of those you could consider ditching the bowl and feeding them out of a kong, likit mat or similar, these not only slow them down but they are fun too, making dinner times even more enjoyable.

Feeding times

Dogs thrive on routine, and so it’s a good idea to feed your dog at the same times each day. Most dogs do well tucking into their food two or three times a day, ideally morning and evening, with a lunch if your schedule allows it. This helps their metabolism to remain stable and has the added benefit of you knowing when you need to have the poop bags to hand!

Puppies, of course, need to be fed more frequently, 3 or 4 times a day, as do some pooches that are fussy eaters or have medical conditions.

What's the difference between dog food, puppy food and senior dog food?

Puppies need more calories and protein than adult dogs in part due to their boundless energy and playfulness but also because around 50% of their intake goes into tissue growth and development.

Conversely, senior dogs tend to slow down when they reach their autumn years, just like us, and therefore need fewer calories whereas a healthy adult dog requires somewhere between the two.

These different nutritional requirements can be met by feeding an age-appropriate dog food. With some natural foods (e.g. Pure Pet Food) this simply requires adjusting the quantity, but manufacturers of biscuit food and kibble tend to produce separate feeds with smaller kibbles.

What to feed your dog

There is an overwhelming array of dog foods on the market now and choosing the pawfect one for your dog is all down to you, it’s one of the most significant decisions you’ll ever make on behalf of your pet.

A lot depends on the needs of your individual pooch, your budget, and convenience often plays a part for many of us. That said though it’s best to aim to feed as natural a diet as you can.

Raw feeding is very natural, healthy and lots of dogs thrive on it, but not everyone wants to have to remember to defrost or has the freezer space to store endless trays of dog food. That doesn’t mean that you can’t feed your dog a healthy, low processed diet though – there are alternatives, full of goodness, human-grade meat and superfoods (eg. air dried), that are still convenient to feed and easy to store – the best of both worlds if you ask me!

Kibble, although still, the most popular choice amongst dog owners in the UK is often not an ideal one. Most contain rendered meat that is processed at very high temperatures and pressures destroying some of the nutrients and often they contain a high proportion of fillers such as wheat which, although not harmful to your pooch per se, have no real benefits.

Pure Pet Food offers a solution that is 100% natural, human-grade and high quality. Pure takes human-grade ingredients and gently preserves them through air drying, locking in the nutrients.

Pure foods contain no fillers, gluten, additives or nasties and are high in protein, ensuring a healthy balanced diet for your dog.

This unique air drying gives Pure all of the advantages of both wet and dry food. Adding water allows the food to expand in the bowl rather than the stomach. It also makes it easier to chew, helps to prevent bloating and reduces the risk of dehydration.

Perfect for dogs who have oral health issues from hard to chew brown biscuits that don’t offer any oral health benefits. At the same time, Pure is super easy to store and has a great shelf life.

What should I do if I want to transition my dog to another food?

The general consensus is that dogs should be changed over to a new food slowly, over 4 to 7 days to get them used to a new food and avoid digestive upsets due to the different enzymes your dog’s stomach will need to produce to cope with the new diet.

Start by gradually decreasing the amount of the old food, (start with about 25% new 75% old) and increasing the amount of the new variety in each meal until your dog is consuming 100% of the new food at every meal. Of course, our pooches are all individuals, and some take to change quicker than others so be guided by them.

Changing your dog from raw food to a more convenient natural equivalent such as Pure can be achieved relatively quickly, and it’s not uncommon for healthy dogs consuming a raw diet to switch to a 100% natural, human-grade diet on holiday or if their owner forgets to defrost.

What are some guidelines for checking my dog's weight?

Most dogs are food motivated, and perhaps because of our innate desire to make them happy, lots of us have probably been guilty of giving them an extra few treats or a bit more dinner at one time or another, those puppy dog eyes are hard to resist!

Sadly, the extra loving we think we’re giving our pooches has led to many being overweight or obese. At the other end of the scale, some canines just aren’t that into food, maybe because their diet doesn’t suit them, or they have an underlying health issue.

Others are so exuberant that they require more than the recommended quantity for their size so end up underweight. But how can you judge if your dog’s the right weight – of course, the easiest way is to ask your vet, but you can also get a good idea by paying attention to your dog’s physique.

Can a dog be allergic to food?

Some dogs can be intolerant or allergic to some ingredients in dog foods, usually, those that are included in an over-processed diet such as extruded kibble. These intolerances can manifest as loose or foul-smelling stools, diarrhoea, itchy skin, a failure to maintain weight or your dog could be labelled as a fussy eater.

A few dogs are intolerant to specific proteins, most commonly chicken and beef, yes, the ones that most dog foods contain! Fortunately for these dogs, more manufacturers are making complete foods using an alternative meat source such as duck and fish, so nobody needs to go hungry.

When should you go to your vet?

If your dog isn’t eating, isn’t drinking enough, is drinking too much, or has symptoms that you don’t feel comfortable about such as diarrhoea, vomiting, itchy skin or seems in pain, it’s probably time to pay a visit to your vet.

Many cases can be resolved or improved by a simple change of diet, but it’s always best to get a professional opinion first.

What types of treat are best?

I bet your dog relishes getting an extra treat, and they’re a great way to reward good behaviour, dogs love to know they’re doing a good job and pleasing you.

But treats contain calories too and it’s all too easy to overfeed your pooch by being over-generous with dispensing them. Just like us, those little extras can easily be the cause of an ever-expanding waistline!

That’s why it’s essential to choose healthy, natural, low-calorie snacks for our four-legged friends. To be honest, your dog probably won’t care what the treat is, he’ll just love it that he’s getting a reward, and you’ll have that warm fuzzy feeling inside that you’ve made him happy.

Vegetables such as slices of carrots, green beans and broccoli and fruits like blueberries, pieces of seedless apple or watermelon or slices of banana are a good choice, as they’re healthy and low calorie.

If you prefer shop bought treats go for something that contains only natural ingredients and aren’t highly processed, ideally with the addition of some superfood ingredients that are beneficial to your pooch like the Pure range of treats.

Try to avoid snacks that are high in fat or sugar and those that contain preservatives, and there are lots of them about so start making a habit of studying the ingredients and how they’re made before you buy.

How much should your dog drink

We all know that our dogs should always have access to fresh, clean water, but do you have any idea how much your pooch is drinking or should be drinking? Or do you, like most of us, just keep his water bowls filled up and forget about it?

Well on average, a healthy dog should drink about 14ml to 28ml of water per 450g of body weight per day, depending on his diet, the weather, exercise levels and age. (Puppies tend to need more as do dogs that are sick or on medication.)

For example, a 5-year-old Cockapoo weighing 7kg would need between 217ml and 435ml of water per day. A 5-year-old Chihuahua weighing 3kg would need between 93ml and 186ml of water per day and a 5-year-old Labrador weighing 28kg would need between 870ml and 1.74 litres.

There are some excellent reasons to monitor your dog’s fluid intake and establish what’s normal for him. For instance, drinking too little can cause dehydration, or it could be symptomatic of some medical conditions such as pancreatitis or infections. Drinking too much can cause stomach bloat, electrolyte imbalances or could indicate that your pooch has an infection or diabetes, Cushing’s disease (hyperadrenocorticism) or a thyroid problem.

To check if your dog is well hydrated, you can pinch his skin on the back of his neck, and it should spring back when you release it. If he is dehydrated, it will take longer to move back as the skin has lost moisture. You can also check his gums; they should be moist and a pinkish colour.


We all want to do the right thing by our dogs and ensure that they are living their best lives.

Feeding our fur babies an appropriate natural, human-grade diet that is full of whole foods and healthy ingredients that promote their all-round health has so many benefits and can avoid unnecessary discomfort for our pets and trips to the vets.

If you’re currently feeding a highly-processed brown biscuit, it’s time to reconsider your choice and start investing in your pet’s health (If you’re still not convinced, read this).

Feeding a healthy, natural diet will provide a longer, happier life for your pet with fewer visits to the vets.

If you’d like to switch to a 100% natural, healthy dog food, then check out Pure Pet Food here.

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