Grain Free Food

Written by Dr Helen Byrnes

The USA Federal Drug Administration (FDA) is investigating an increased incidence of Dilated Cardiomyopathy (DCM) in dogs eating diets labelled as grain free or which contain a high proportion of peas, lentils and pulses.  There have been no reported cases in Australia, but some of the foods listed by the FDA are available in Australia.  Some breeds of dogs have a genetic predisposition to DCM but many of the case reports in USA included breeds of dogs not previously known to have a genetic predisposition to the disease.

But why are we feeding grain-free?

Premium diets are generally better than supermarket diets, but they don’t need to be grain free. The grain free myth has been largely based on marketing, and social media. When marketing is driving pet food formulation it’s not surprising that problems could occur.

It can be difficult to distinguish between glossy packaging and marketing, and products that are supported by good research. Small pet food manufacturers might be better at marketing than at nutrition and quality control.

It seems the association between diet and DCM in dogs is complex; it’s not just that the grain free diets are deficient in particular nutrients.  There’s been very little research about the use of grain free diets in dogs so there’s not much known about how they interact in the dog’s gut. Research is now being undertaken to work out what’s happening with grain free foods.

There has been a lot of nutrition science research for pets by some manufacturers. Hill’s Petcare, Mars/Royal Canin/Waltham, and Nestle Purina spend A LOT of money on animal nutrition science research worldwide. Their research focuses on cat and dog nutrient requirements in health and disease, and ensuring that the ingredients that go into their diets are healthful and not harmful to the end consumer (the dog or cat).  The big companies and many small to medium sized pet food and supplement companies also provide nutrition research grants to veterinary schools worldwide.  As veterinarians, we look for solid scientific research and quality control behind a product before recommending it for our patients.

What about Home-made Diets?

The advent of formulated pet food has led to the virtual elimination of many nutritional diseases that were common 30 years ago.  I recommend a premium pet food (not a grain free food) as the basis of a dog’s diet.

Home cooked meals often have limited variability, and in the long-term there’s the potential for nutritional deficiencies.  And unfortunately home cooked meals and obesity seem to go hand in hand.  I’m not sure if that’s just a lack of portion control, but it seems to be also that often the dog doesn’t feel as full and asks for more.

What should you do?

  • Reconsider your dog’s diet. If you’re feeding a boutique, grain-free, or exotic ingredient diet, look at changing to a diet with more typical ingredients made by a company with a long track record of producing good quality diets.  Be careful about pet food rating websites that rank pet foods either on opinion or based on myths and subjective information. Ask your veterinarian for advice.
  • If you’re feeding your dog a boutique, grain-free, or exotic ingredient diet, watch for early signs of heart disease – weakness, slowing down, less able to exercise, short of breath, coughing, or fainting. Seek veterinary advice if you see these signs – it might not be heart disease, but it’s worth checking.

What about cats?

There have been no reports of a relationship between DCM, grain free diets, and cats so far.  But as we don’t know the mechanism of the problem, cats could be affected. Reconsider your use of a grain free diet for your cat.


Want to know more?

The July 2019 FDA report on the investigation is available here.

Tufts University (Veterinary) Clinical Nutrition Service Update is available here.