Grain Free Is grain free better for dogs? What the evidence says in 2026

For most healthy dogs, grain-free food isn't automatically better or worse than food with grains. What matters more is the whole recipe: where the protein comes from, what replaces the grain, and whether your dog does well on it.

We craft grain-free recipes, so we have a stake in this question. That's why we've set out the research as it stands in October 2026, including the parts that are still unresolved, with every study linked so you can read it for yourself.

The short answer

• Most healthy dogs don't need to avoid grains. Grains are rarely the cause of food reactions in dogs.

• Grain-free can suit some dogs well. That includes dogs that react to wheat and dogs that thrive on meat-led recipes.

• The heart health question is still open. Some grain-free diets high in pulses (peas, lentils, chickpeas, and beans) have been linked with a heart condition called DCM, but no study has shown that grain-free food causes it.

• Some breeds deserve a vet chat first. Golden Retrievers and breeds with an inherited risk of heart disease are the main ones.

What "grain-free" means on a label

Grain-free means a recipe contains no cereal grains, such as wheat, barley, oats, rye, rice, or corn (maize). The carbohydrate usually comes from potato, sweet potato, tapioca (made from the cassava root), or pulses instead.

Three things it doesn't tell you:

• Whether the food is low in carbohydrate. Grain-free recipes still contain starch, just from other sources.

• Whether it's gluten-free. Grain-free food is free of gluten, but the reverse isn't true. Rice and corn contain no gluten, so a gluten-free food can still contain grains.

• Anything about quality on its own. The label tells you what's been left out, not what's been put in.

For a wider look at formats, our guide to different dog food types covers wet, dry, and raw-inspired options.

Are grains bad for dogs?

No. Over thousands of years living alongside people, dogs developed more copies of a gene that helps them digest starch than wolves have (Axelsson et al., 2013). Cooked grains can be a useful source of energy and fibre for many dogs.

The idea that grains are a common trigger for food sensitivities doesn't hold up well either. A review of published studies looked at the trigger foods in 297 dogs with confirmed adverse food reactions, which is a catch-all term covering food allergies and intolerances (Mueller et al., 2016):

• Beef: 34%

• Dairy: 17%

• Chicken: 15%

• Wheat: 13%

• Corn: 4%

• Rice: 2%

Some dogs reacted to more than one food. For a sensitive dog, the protein in a recipe is usually a more useful place to start than the grain. Food allergies are also less common than many owners expect, accounting for under 1% of skin problems in dogs (Zhang et al., 2025). Our guide to what hypoallergenic dog food really means goes into this in more depth.

The heart health question: where the DCM evidence stands in 2026

DCM (dilated cardiomyopathy) is a disease of the heart muscle. The heart enlarges and pumps less strongly, which can lead to heart failure. Some breeds inherit a risk of it, and it was well known long before grain-free food became popular.

What happened

• 2018: The US Food and Drug Administration (FDA) began investigating reports of DCM in dogs, including breeds not usually affected.

• 2019: Of the reports received between January 2014 and April 2019, more than 90% involved grain-free diets and 93% involved diets containing peas and/or lentils.

• December 2022: The FDA said the reports alone don't establish a cause, and that it doesn't plan further public updates until there's meaningful new scientific information (FDA, 2022).

As of October 2026, that December 2022 update is still the latest on the FDA's investigation page. The FDA's own lab testing also found that average protein, fat, and taurine levels were similar in the grain-free and grain-containing foods it analysed.

What the research has found

• Golden Retrievers: In a study of 24 Golden Retrievers with DCM and low taurine, 23 were eating grain-free diets, legume-rich diets, or both. After a diet change and taurine supplements, 23 of the 24 showed significant improvement on their heart scans (Kaplan et al., 2018).

• Healthy dogs: A study of 188 healthy dogs from four breeds found no differences in heart scans between diet types. Dogs eating grain-free diets had slightly higher levels of troponin, a blood marker released when heart muscle cells are under strain. The researchers said the clinical importance of this is unclear (Adin et al., 2021).

• Dogs already diagnosed: Among 67 dogs with DCM and heart failure, those previously fed grain-free diets that survived the first week and changed diet lived a median of 344 days, against 253 days for dogs that had eaten grain-inclusive diets (Walker et al., 2022). This suggests some diet-associated cases may be partly reversible.

• The longest controlled trial: In an 18-month study, 60 healthy dogs ate one of four diets, including grain-free and grain-inclusive recipes with peas. Taurine and heart markers stayed normal, and every dog was judged clinically normal for DCM at the end (Morris et al., 2025). The study was small and funded by a pet food manufacturer, so it adds to the picture rather than settling it.

The UK picture

Most of this research comes from the US. When the FDA first raised the issue, the UK pet food trade body said "there is no information to suggest a similar issue in the UK/Europe." The British Veterinary Association (BVA) said there was "insufficient evidence to substantiate any of the beneficial health claims of a grain-free diet" and advised caution (MRCVS).

Our reading of it

Taken together, the evidence shows an association between some high-pulse, grain-free diets and heart changes in some dogs. It doesn't show that grain-free food causes DCM. Two recent reviews land in the same place: the link is real enough to take seriously, and long-term research is still needed (Mornard et al., 2025; Zhang et al., 2025).

What replaces the grain matters more than the grain itself

Researchers aren't really studying the absence of grain. They're looking at what fills the space: pulses, potatoes, and how much of the protein comes from plants rather than meat. One study, for example, grouped diets by whether peas, lentils, or potatoes appeared in the first 10 ingredients (Adin et al., 2021).

A two-minute label check

UK pet food labels list ingredients in descending order of weight (Regulation (EC) No 767/2009). That makes the ingredient list a quick way to see how a recipe is built:

1. Read the first two or three ingredients. Named meat or fish with a declared percentage tells you where most of the protein comes from.

2. Find the pulses. Look for peas, lentils, chickpeas, and beans, plus concentrated forms such as pea protein or pea fibre. A concentrated pulse protein means pulses are supplying protein, not just carbohydrate.

3. Look for the word "complete". A complete food is designed to provide all the nutrients your dog needs. A complementary food needs to be fed alongside something else.

4. Match it to your dog. If your dog is a breed with an inherited heart risk, take the ingredient list to your vet.

Our own label, as an example

Here's how two of our recipes read. Our Free Run Chicken dry recipe lists Chicken (66%) and Dried Chicken (14%) first, then Sweet Potato, Tapioca, Apple, Chickpeas, and Peas. Our Salmon dry recipe follows the same pattern, with Salmon (64%) and Dried Salmon (16%) first.

So yes, our dry recipes contain pulses, and by the "first 10 ingredients" measure used in some studies they'd sit in that group. The difference is the balance. Meat and Fish Ingredients make up 80% of each dry recipe, so the pulses play a supporting role rather than standing in for meat. We'd rather you see that clearly than have to find it yourself.

Which dogs need extra care

• Golden Retrievers. This breed appears to be more prone to DCM linked to low taurine, an amino acid-like nutrient that helps the heart muscle work. Dogs normally make their own taurine from building blocks found in animal protein (Kaplan et al., 2018).

• Breeds with an inherited risk. In a study of 369 dogs with DCM referred to a cardiology centre in England, the most common breeds were Dobermanns (59), Boxers (53), Great Danes (38), Cocker Spaniels (30), and German Shepherds (24) (Martin et al., 2009). If you share your home with one, our guides for Cocker Spaniels and German Shepherds cover their wider nutritional needs.

Whatever you feed, watch for decreased energy, coughing, difficulty breathing, or collapse, and contact your vet promptly if you notice any of them (FDA, 2022).

At your next check-up, it's worth asking:

• Whether a heart scan (an echocardiogram, which is an ultrasound of the heart) makes sense for your dog's breed and age.

• Whether a whole blood taurine test would be useful.

• How your dog's current recipe fits with their health history. Bring the bag or a photo of the ingredient list.

When grain-free can be a sensible choice

Grain-free can work well for:

• Dogs with a confirmed grain sensitivity, such as a reaction to wheat identified through a vet-guided trial.

• Dogs that thrive on meat-led recipes, with steady energy, a healthy body condition, and consistent stools.

• Some fussy eaters, who may be more interested in a recipe built around meat or fish.

If you suspect a food sensitivity, an elimination trial is the most reliable way to find the cause. Your dog eats one carefully chosen diet and nothing else, then foods are reintroduced to see what triggers a reaction. In dogs with food reactions, signs settled in more than 85% by five weeks and more than 95% by eight weeks (Olivry et al., 2015).

A recipe built around one named protein makes this easier, because you know exactly what your dog is eating. Our guide to the best hypoallergenic dog food explains how to choose one.

How to switch to or from a grain-free food

• Take seven to 10 days. Start with roughly a quarter new food mixed with the old, then half and half, then three quarters, then all new.

• Weigh portions in grams. Follow the feeding guide on the pack, as recipes differ in how nutrient-dense they are.

• Expect a little change. Slightly softer stools for a day or two can happen. If you notice vomiting, diarrhoea that lasts longer, or your dog stops eating, slow down and speak to your vet.

• Change one thing at a time. Pausing new treats during a switch makes it easier to see how your dog is getting on.

If your dog tends to have a sensitive tummy, our guide to why dogs get gassy has more on supporting digestion through a food change.

How AATU recipes fit

Every AATU recipe is grain-free. Here's what goes into them:

• 80/20 dry recipes: 80% Meat and Fish Ingredients and 20% Superfood Blend™, our mix of fruits, vegetables, herbs, and botanicals.

• 90/10 wet recipes: up to 90% Meat and Fish Ingredients for dogs who enjoy a wetter meal.

• A named protein at the heart of each recipe, such as Free Run Duck or Free Run Turkey.

• Low and Slow™ cooking, our small-batch method that helps lock in nutrients.

You can explore the full grain-free dog food collection, or go straight to our dry recipes and wet recipes. If you'd like to try a few proteins first, the wet variety pack is a good place to start. For the thinking behind our ratios, see what 80/20 dog food means.

FAQs

Do vets recommend grain-free dog food?

Not as a default for every dog. Vets tend to recommend grain-free food for specific reasons, such as a grain sensitivity confirmed through an elimination trial. For a healthy dog, most vets will focus on the overall recipe and your dog's body condition rather than on grains alone.

What is the downside of grain-free dog food?

The main downside is uncertainty, as some grain-free diets high in pulses have been linked with heart changes in some dogs and that research isn't settled. Grain-free recipes can also cost more, and most dogs don't need to avoid grains.

Can dogs react to grain-free food?

Yes. Most food reactions in dogs are triggered by proteins such as beef, dairy, and chicken, which can appear in grain-free recipes too. If symptoms carry on after a switch, ask your vet about an elimination trial.

Is grain-free food OK for puppies?

It can be, as long as the recipe is formulated for growth, so look for "puppy" or "all life stages" on the label. Large-breed puppies need carefully controlled calcium and energy to grow at a steady pace, so check if the recipe suits their expected adult size. Our guide to feeding large breeds and our puppy recipes are good places to start.

Is rice a grain in dog food?

Yes, rice is a cereal grain, so a recipe containing rice isn't grain-free. Potato, sweet potato, and tapioca aren't grains, which is why they often appear in grain-free recipes instead.

Can you mix grain-free and grain-inclusive dog food?

Yes, as long as both foods are complete and the combined amount suits your dog's needs. Introduce any new food gradually and weigh portions in grams so your dog isn't overfed.

Will grain-free food help my dog's itchy skin?

Only if a grain is the trigger, which is uncommon. Itchy skin has many possible causes, including fleas and environmental triggers such as pollen and dust mites, so it's worth speaking to your vet before changing food.