Introduction
Among the timeless questions that are debated endlessly from generation to generation, such as “What is the meaning of life?” and “Does the refrigerator light go off when the door is closed?” is one that veterinarians and cat owners are particularly familiar with: “Is feeding canned or dry food better for cats?” Cat lovers, and many vets, often have strong and absolute opinions on this question, and disagreements on the subject tend to be about as amicable as disagreements about politics and religion. 

The most widely held belief seems to be that canned foods are healthier for cats than dry diets. This is predicated on two key arguments:

1. As obligate carnivores, cats cannot thrive on dietary carbohydrates, and canned diets are low-carb compared with kibble. Therefore, dry diets are more likely to lead to obesity and diabetes mellitus (DM), two common and important feline health problems.^1–5
   
   
2. Cats eating dry food don’t drink enough water, and this increases the risk of chronic kidney disease (CKD) and lower urinary tract diseases, such as feline interstitial cystitis (FIC) and urolithiasis. Feeding canned foods will maintain better hydration and promote dilute urine, and this will reduce the risk of these diseases.^4,6,7

These are plausible and logically sound arguments, but the history of medicine is full of plausible hypotheses that turned out to be wrong. It is not enough to make a good argument based on general principles. To know what is really best for our patients, we must test such arguments experimentally and follow the evidence, whether or not it supports seemingly obvious, “common sense” beliefs. 

The question of whether cats are healthier when fed canned or dry food is, unfortunately, far more complicated that it seems. There are many nutritional variables which affect health and disease and which are not determined solely by whether the food is dry or canned. 

Macronutrient content can vary dramatically between diets, and while dry foods are typically higher in carbohydrates than canned diets, they can be higher or lower than canned foods in fat or protein. The micronutrient content of a diet is also critical, as the consequences of feeding taurine deficient diets to cats illustrates. Other variables, such as calorie density, the amount of food fed, and the feeding pattern (e.g. number of meals per day) can have as much or more impact on health than the general form of the diet.

Even the basic assumptions of the arguments in favor of canned diets are not always as clear as they might seem. Cats certainly process carbohydrates differently from more omnivorous species, but that doesn’t translate into a simple equation that ”carbohydrates = bad for cats.” The type and relative amount of carbohydrates fed make a great deal of difference. And while canned food unquestionably contains more water than dry food, the idea that cats eating canned food are better hydrated and have more dilute urine turns out not to be consistently true. 

Cats and Carbs
The debate about the effect of dietary carbohydrates on cats has raged for decades. A couple of reviews have recently summarized the evidence, and simplistic, general conclusions are difficult to justify.^1,8It is clear that cats do metabolize carbohydrates differently than dogs and humans. However, the type of carbohydrate (simple or complex) and the feeding pattern both have significant effects of postprandial glucose levels and other measures. Cats can utilize carbohydrates as an energy source, and they can adapt metabolically to different macronutrient ratios in the diet, so the simplistic notion of carbohydrates as “toxic” to cats isn’t supported.

Research evidence generally shows no adverse effects on resting glucose or insulin sensitivity in cats fed typical types and levels of dietary carbohydrates. Diets with greater than 50% of calories from carbohydrates, especially when fed once daily rather than ad libor as multiple meals, can generate higher and more prolonged spikes in blood glucose, but even this does not appear to achieve levels associated with harm in experimental studies.

Though there is some inconsistency among studies, most research has failed to find that dietary carbohydrates is a significant risk factor for DM in cats.^1,8One study even found cats who developed diabetes were less likely to be fed dry foods than cats without DM.⁹There is evidence that reduced-carbohydrate diets may be useful in management of feline DM, though such diets can be counterproductive and promote obesity if they are very high in fat.^1,10

Cats and Water
Cats can produce more highly concentrated urine than dogs and have lower weight-specific water requirements.⁶It has been argued that dry diets are associated with less overall water intake and that they promote dehydration and may increase the risk of CKD and other urinary tract diseases.⁴Some research has found that cats will drink less water when eating low-moisture diets.^4,6However, other studies contradict this finding and identify no difference in water turnover and intake or body water content between cats fed dry and canned diets.⁶There are many factors that affect water intake in cats other than the form of the food, including the protein and mineral content and the energy density, so simply feeding a canned diet is not guaranteed to increase water intake or reduce urine specific gravity.⁶

Some studies have identified consumption of dry diets as a risk factor for FIC and urolithiasis while others have not confirmed this link.⁶Other research has even found that cats who develop FIC are morelikely to be fed canned food than control cats, suggesting canned foods could increase FIC risk in some cases.¹¹Similarly, while dry diets are often cited as a risk factor for the development of CKD, research has consistently failed to support this purported association.^6,12,13And while canned diets certainly have a role in the management of CKD and urolithiasis, moisture content is not the only relevant variable, and dry diets can have benefits in patients with these conditions as well.^6,14

Higher moisture diets are typically less calorie-dense than lower-moisture diets, and it has been suggested that canned diets may help prevent or treat obesity in cats. Other factors are clearly also relevant, of course, such as the specific composition of the diet, the amount fed, and the feeding pattern. It is clearly possible to maintain cats in a lean body condition with dry foods and to develop and perpetuate obesity while feeding canned diets. Overall, however, it is likely that high-moisture diets, including canned foods or dry diets with added water, may be beneficial in preventing and managing feline obesity.⁶

Conclusions
Regular readers will not be surprised to see that the simple answer, canned foods are better/worse than dry foods for cats, is not the true answer. “It depends” is a much less satisfying response to questions about the relative merits of canned food and kibble, but it is more likely to lead us to the best dietary strategy for individual patients. 

Overall, concerns about the health effects of dietary carbohydrates in cats are typically exaggerated, and dry diets should not be avoided on the basis of the idea that they have too much carbohydrate and promote obesity and DM. The specific nutrient and calorie content of the diet is more important than the form it comes in.

Canned diets are higher in moisture than dry foods, and while it is unclear how much impact this has on the risk of urinary tract disease, it does seem likely this characteristic may help owners control calorie intake and weight in their cats. 

So when our clients ask whether they should feed canned or dry food to their cats, rather than giving a satisfying, simple answer that is probably wrong, we should be prepared to discuss the evidence and the nuances of the issue in the context of the individual pet. This is the essence of evidence-based practice. 

References

1.        Verbrugghe A, Hesta M. Cats and Carbohydrates: The Carnivore Fantasy? Vet Sci. 2017;4(4):55. doi:10.3390/vetsci4040055

2.        Rand JS, Fleeman LM, Farrow HA, Appleton DJ, Lederer R. Canine and feline diabetes mellitus: nature or nurture? J Nutr. 2004;134(8 Suppl):2072S-2080S. http://www.ncbi.nlm.nih.gov/pubmed/15284406. Accessed June 14, 2019.

3.        Buffington CAT. Dry foods and risk of disease in cats. Can Vet J = La Rev Vet Can. 2008;49(6):561-563. http://www.ncbi.nlm.nih.gov/pubmed/18624064. Accessed June 14, 2019.

4.        Zoran DL. The carnivore connection to nutrition in cats. J Am Vet Med Assoc. 2002;221(11):1559-1567. doi:10.2460/javma.2002.221.1559

5.        Gomez-Mejias Y. Does Grain Actually Predispose Our Cats to Gain Weight? Vet Evid. 2019;4(2). doi:10.18849/ve.v4i2.201

6.        Larsen JA. The role of water in disease management. In: 2018 ACVIM Forum. Seattle, WA; 2018.

7.        Markwell PJ, Buffington CT, Smith BHE. The Effect of Diet on Lower Urinary Tract Diseases in Cats. J Nutr. 1998;128(12):2753S-2757S. doi:10.1093/jn/128.12.2753S

8.        Laflamme D. Cats and carbohydrates: Why is this still controversial? In: 2018 ACVIM Forum. Seattle, WA; 2018.

9.        Sallander M, Eliasson J, Hedhammar A. Prevalence and risk factors for the development of diabetes mellitus in Swedish cats. Acta Vet Scand. 2012;54(1):61. doi:10.1186/1751-0147-54-61

10.      Nguyen PG, Dumon HJ, Siliart BS, Martin LJ, Sergheraert R, Biourge VC. Effects of dietary fat and energy on body weight and composition after gonadectomy in cats. Am J Vet Res. 2004;65(12):1708-1713. http://www.ncbi.nlm.nih.gov/pubmed/15631038. Accessed June 14, 2019.

11.      Lund HS, Sævik BK, Finstad ØW, Grøntvedt ET, Vatne T, Eggertsdóttir A V. Risk factors for idiopathic cystitis in Norwegian cats: a matched case-control study. J Feline Med Surg. 2016;18(6):483-491. doi:10.1177/1098612X15587955

12.      Finch NC, Syme HM, Elliott J. Risk Factors for Development of Chronic Kidney Disease in Cats. J Vet Intern Med. 2016;30(2):602-610. doi:10.1111/jvim.13917

13.      Bartlett PC, Van Buren JW, Bartlett AD, Zhou C. Case-control study of risk factors associated with feline and canine chronic kidney disease. Vet Med Int. 2010;2010. doi:10.4061/2010/957570

14.      Roudebush P, Polzin DJ, Ross SJ, Towell TL, Adams LG, Forrester SD. Therapies for Feline Chronic Kidney Disease. J Feline Med Surg. 2009;11(3):195-210. doi:10.1016/j.jfms.2009.01.004

Pet owners frequently project their beliefs about human health onto their companion animals. Anxieties about purported harms from vaccines in children, for example, have spurred an anti-vaccination movement among vets and pet owners.^1–4Beliefs in alternative medical therapies for people, such as herbal medicine and acupuncture, may motivate pet owners to seek such treatments for their animals. But perhaps the most common example of this phenomenon is the translation of dietary beliefs and fads from human nutrition to animal feeding practices.⁵

This projection of human dietary practices onto pets takes many forms. On the heels of a wave of hysteria about gluten and the health effects of grains in humans, we saw the rise in popularity of grain-free pet foods, which now make up close to half of commercial diets for dogs and cats.⁶Organic ingredients are often marketed to pet owners as having health benefits based on the belief that this is true for people, despite the lack of real evidence for this in humans or in other animals.⁷And among those who minimize or avoid animal products in their own diet, there is significant interest in feeding such vegetarian or vegan diets to their pets.⁸

People may avoid meat or other animal products in their diet for a variety of reasons, including concerns about food animal welfare, beliefs about the health effects of plant-based and animal-based foods, and religious dietary restrictions. Surveys of pet owners indicate that those who follow a vegan diet (eating no animal-based foods) or other vegetarian diets (limited consumption of some types of animal-based foods) sometimes feel discomfort at violating their own dietary rules in the feeding of their dogs and cats, especially if their own food choices are driven by religious or ethical concerns.^8–11They have a clear interest and motivation to feed vegetarian or vegan diets to their pets, but many do not because of concerns about the health effects of such diets on their pets.⁸

Beliefs about the nutritional requirements of dogs and cats are often based on the notion that whatever wild canids and felids eat must be a “natural,” and thus a healthy diet for our pets. However, wild carnivores often suffer from malnutrition, parasitism, and other ills associated with their diet, so it is a mistake to imagine that the diet available to them in the wild is perfectly suited to optimize their health.^12–23Natural history does have an influence the nutritional requirements of a species, but these requirements are not always best met by feeding a diet identical to that eaten by the wild ancestors of modern animals. This is especially true for animals that have been domesticated, a process which induces significant changes to the anatomy and physiology of domestic species.

Dogs have been dramatically impacted by their long association with humans. Some of these changes are obvious, and their relevance to the concept of a “natural” diet like that of wolves and wild dogs is clear. It is unlikely that a pack of feral pugs or French bulldogs will even be seen running down and savaging an elk or antelope, and the idea that this would be an optimal diet for them is clearly ridiculous. However, even breeds with a more typically canine anatomy have undergone changes in morphology and physiology that reflect their adaptation to human foods. From their dentition to their ability to digest starches and taste sweetness, dogs have been shaped by domestication, and they are well-suited to an omnivorous diet.^24–27

In theory, then, dogs should be able to thrive on vegetarian or vegan diets. However, there have been few studies demonstrating this, and such diets can still be problematic. A vegan diet must be properly and carefully formulated to meet the nutritional needs of dogs, and there is less room for error than with diets containing animal ingredients. Numerous studies of commercial vegan and vegetarian pet foods have found formulation errors and inadequacies in essential nutrients.^9,28Some studies have also found mammalian DNA in such diets, suggesting they may not even be accurately labeled as vegetarian or vegan.²⁹

Even diets which appear adequate on paper or in laboratory testing, however, may not support normal health under real-world conditions. Most commercial grain-free diets, for example, should be nutritionally complete for dogs, yet recent reports of cardiomyopathy in dogs eating such diets suggest a serious health risk for some individuals fed these diets.^30–32At present, there are only short-term studies and uncontrolled, low-quality case series evaluating the health of dogs fed vegan or vegetarian diets.^9,33Such limited evidence leaves significant uncertainty about the risks and benefits of such diets for domestic dogs.

Cats have been more lightly touched by domestication and artificial selection than dogs, and they are clearly still obligate carnivores.^34,35This does not mean they are healthiest when fed only raw birds and small mammals, and in fact the evidence indicates this is not the safest or healthiest diet for domestic cats.^36,37However, domestication has had limited effects on the physiology of cats, and their dietary requirements are unlikely to be effectively met by plant-only diets. The need for preformed vitamin A, taurine and other specific amino acids lacking in plant-based foods, and other specific and known dietary requirements of cats makes it unlikely that long-term feeding of vegan diets will support good health in this species.^35,38

There are few studies evaluating the health effects of plant-based diets on cats. Some research on cats fed commercial vegetarian diets by their owners have found deficiencies in some nutrients in some cats, but the evidence is limited and of low quality, so no robust conclusions can be drawn.^9,39–41

Bottom Line

There is no evidence that vegetarian diets have health benefits for dogs and cats, and no real reason to believe they should based on the physiology and nutritional requirements of these species. Pet owners may choose to feed such diets due to their philosophical or religious beliefs, but veterinarians should make it clear that any potential health benefits of vegetarianism for humans likely do not apply to our dogs and cats.

Dogs are omnivores shaped by domestication to be able to eat both plant and animal foods, and in theory they should be able to thrive on vegetarian or vegan diets. However, these diets must be carefully formulated, and many commercial vegetarian dog foods do not appear to be nutritionally adequate. There is also little reliable research evidence showing that dogs can remain healthy fed only a vegan diet. Given the unexpected health problems seen with theoretically adequate grain-free diets, we should be cautious about the potential risks of vegetarian diets for dogs until there is better evidence showing their long-term health effects.

Cats are clearly obligate carnivores with nutritional requirements that are unlikely to be effectively met by vegan diets. Such diets offer only risks and no benefits for cats and should be avoided.

References

1.        Clifton J. Stop the Shots!?: Are Vaccinations Killing Our Pets?New York, NY: Foley Square Books; 2007.

2.        Duan N. Inside the World of Pet Anti-Vaxxers. The Awl.com. January 2018.

3.        Kluger J. Some Anti-Vaxxers Aren’t Getting Their Pets Vaccinated. Here’s Why That’s So Dangerous. Time.com. March 2019.

4.        Ducharme J. Veterinary Group: Dogs Can’t Get Autism, So Please Keep Vaccinating Them. Time.com. 2018.

5.        Walet E. Are trends in Human Food reflected in Pet Food Purchase? 2015. https://dspace.ou.nl/bitstream/1820/6538/1/Walet E scriptie.pdf. Accessed December 20, 2018.

6.        Phillips-Donaldson D. Are grain-free pet foods truly healthy and sustainable? Pet Food Ind. 2017.

7.        Smith-Spangler C, Brandeau ML, Hunter GE, et al. Are Organic Foods Safer or Healthier Than Conventional Alternatives? Ann Intern Med. 2012;157(5):348. doi:10.7326/0003-4819-157-5-201209040-00007

8.        Dodd SAS, Cave NJ, Adolphe JL, Shoveller AK, Verbrugghe A. Plant-based (vegan) diets for pets: A survey of pet owner attitudes and feeding practices. Suchodolski JS, ed. PLoS One. 2019;14(1):e0210806. doi:10.1371/journal.pone.0210806

9.        Knight A, Leitsberger M, Knight A, Leitsberger M. Vegetarian versus Meat-Based Diets for Companion Animals. Animals. 2016;6(9):57. doi:10.3390/ani6090057

10.      Rothgerber H. A meaty matter. Pet diet and the vegetarian’s dilemma. Appetite. 2013;68:76-82. doi:10.1016/j.appet.2013.04.012

11.      Wakefield LA, Shofer FS, Michel KE. Evaluation of cats fed vegetarian diets and attitudes of their caregivers. J Am Vet Med Assoc. 2006;229(1):70-73. doi:10.2460/javma.229.1.70

12.      Tidière M, Gaillard J-M, Berger V, et al. Comparative analyses of longevity and senescence reveal variable survival benefits of living in zoos across mammals. Sci Rep. 2016;6:36361. doi:10.1038/srep36361

13.      Mukherjee S, Heithaus MR. Dangerous prey and daring predators: a review. Biol Rev. 2013;88(3):550-563. doi:10.1111/brv.12014

14.      Woodroffe R, Davies-Mostert H, Ginsberg J, et al. Rates and causes of mortality in Endangered African wild dogs Lycaon pictus: lessons for management and monitoring. Oryx. 2007;41(02):215. doi:10.1017/S0030605307001809

15.      Mech LD. Productivity, Mortality, and Population Trends of Wolves in Northeastern Minnesota. J Mammal. 1977;58(4):559-574. doi:10.2307/1380004

16.      Young TP. Natural Die-Offs of Large Mammals: Implications for Conservation. Conserv Biol. 1994;8(2):410-418. doi:10.1046/j.1523-1739.1994.08020410.x

17.      Holmes JC, Podesta R. The helminths of wolves and coyotes from the forested regions of Alberta. Can J Zool. 1968;46(6):1193-1204. doi:10.1139/z68-169

18.      Bosch G, Hagen-Plantinga EA, Hendriks WH. Dietary nutrient profiles of wild wolves: insights for optimal dog nutrition? Br J Nutr. 2015;113(S1):S40-S54. doi:10.1017/S0007114514002311

19.      Choquette LPE, Gibson GG, Kuyt E, Pearson AM. Helminths of wolves, Canis lupusL., in the Yukon and Northwest Territories. Can J Zool. 1973;51(10):1087-1091. doi:10.1139/z73-158

20.      Amanda A. Parasites of the African painted dog (Lycaon pictus) in captive and wild populations: Implications for conservation. 2011. http://researchrepository.murdoch.edu.au/id/eprint/10519/2/02Whole.pdf.

21.      Berentsen AR, Becker MS, Stockdale-Walden H, Matandiko W, McRobb R, Dunbar MR. Survey of gastrointestinal parasite infection in African lion ( Panthera leo), African wild dog ( Lycaon pictus) and spotted hyaena ( Crocuta crocuta) in the Luangwa Valley, Zambia. African Zool. 2012;47(2):363-368. doi:10.1080/15627020.2012.11407561

22.      Fuchs B. Sarcoptic mange in the Scandinavian wolf population. 2014. https://brage.bibsys.no/xmlui/bitstream/handle/11250/222199/Boris Fuchs.pdf?sequence=1. Accessed December 28, 2018.

23.      Benson JF, Mills KJ, Loveless KM, Patterson BR. Genetic and environmental influences on pup mortality risk for wolves and coyotes within a Canis hybrid zone. Biol Conserv. 2013;166:133-141. doi:10.1016/J.BIOCON.2013.06.018

24.      Vilà C, Maldonado JE, Wayne RK. Phylogenetic relationships, evolution, and genetic diversity of the domestic dog. J Hered. 90(1):71-77. http://www.ncbi.nlm.nih.gov/pubmed/9987908. Accessed October 27, 2018.

25.      Serpell J, Barrett P. The Domestic Dog?: Its Evolution, Behavior and Interactions with People. Second edition.; 2017. https://www.worldcat.org/title/domestic-dog-its-evolution-behavior-and-interactions-with-people/oclc/987274028&referer=brief_results. Accessed October 27, 2018.

26.      Axelsson E, Ratnakumar A, Arendt M-L, et al. The genomic signature of dog domestication reveals adaptation to a starch-rich diet. Nature. 2013;495(7441):360-364. doi:10.1038/nature11837

27.      Reiter T, Jagoda E, Capellini TD. Dietary Variation and Evolution of Gene Copy Number among Dog Breeds. 2016. doi:10.1371/journal.pone.0148899

28.      Kanakubo K, Fascetti AJ, Larsen JA. Assessment of protein and amino acid concentrations and labeling adequacy of commercial vegetarian diets formulated for dogs and cats. J Am Vet Med Assoc. 2015;247(4):385-392. doi:10.2460/javma.247.4.385

29.      Kanakubo K, Fascetti AJ, Larsen JA. Determination of mammalian deoxyribonucleic acid (DNA) in commercial vegetarian and vegan diets for dogs and cats. J Anim Physiol Anim Nutr (Berl). 2017;101(1):70-74. doi:10.1111/jpn.12506

30.      Adin D, DeFrancesco TC, Keene B, et al. Echocardiographic phenotype of canine dilated cardiomyopathy differs based on diet type. J Vet Cardiol. 2019;21:1-9. doi:10.1016/J.JVC.2018.11.002

31.      Kaplan JL, Stern JA, Fascetti AJ, et al. Taurine deficiency and dilated cardiomyopathy in golden retrievers fed commercial diets. Loor JJ, ed. PLoS One. 2018;13(12):e0209112. doi:10.1371/journal.pone.0209112

32.      Freeman LM, Stern JA, Fries R, Adin DB, Rush JE. Diet-associated dilated cardiomyopathy in dogs: what do we know? J Am Vet Med Assoc. 2018;253(11):1390-1394. doi:10.2460/javma.253.11.1390

33.      Brown WY, Vanselow BA, Redman AJ, Pluske JR. An experimental meat-free diet maintained haematological characteristics in sprint-racing sled dogs. Br J Nutr. 2009;102(09):1318. doi:10.1017/S0007114509389254

34.      MacDonald ML, Rogers QR, Morris JG. Nutrition of the Domestic Cat, a Mammalian Carnivore. Annu Rev Nutr. 1984;4(1):521-562. doi:10.1146/annurev.nu.04.070184.002513

35.      Morris JG. Idiosyncratic nutrient requirements of cats appear to be diet-induced evolutionary adaptations. Nutr Res Rev. 2002;15(01):153. doi:10.1079/NRR200238

36.      Glasgow A, Caver N, Marks S, Pedersen N. Role of Diet in the Health of the Feline Intestinal Tract and in Inflammatory Bowel Disease.; 2002. http://www.vetmed.ucdavis.edu/ccah/530-752-7295. Accessed December 28, 2018.

37.      Schlesinger DP, Joffe DJ. Raw food diets in companion animals: a critical review. Can Vet J = La Rev Vet Can. 2011;52(1):50-54. http://www.ncbi.nlm.nih.gov/pubmed/21461207. Accessed October 27, 2018.

38.      Weeth L, Chandler M. Vegetarian Diets. Clin Br. 2015;(January):61-63. https://www.cliniciansbrief.com/article/vegetarian-diets. Accessed April 29, 2019.

39.      Leon A, Bain SA, Levick WR. Hypokalaemic episodic polymyopathy in cats fed a vegetarian diet. Aust Vet J. 1992;69(10):249-254. http://www.ncbi.nlm.nih.gov/pubmed/1359869. Accessed April 29, 2019.

40.      Wakefield L, Michel KE. Taurine And Cobalamin Status of Cats Fed Vegetarian Diets. J Anim Physiol Anim Nutr (Berl). 2005;89(11-12):427-428. doi:10.1111/j.1439-0396.2005.00611_2.x

41.      Gray CM, Sellon RK, Freeman LM. Nutritional adequacy of two vegan diets for cats. J Am Vet Med Assoc. 2004;225(11):1670-1675. http://www.ncbi.nlm.nih.gov/pubmed/15626215. Accessed April 29, 2019.

The FDA has released a new update about the ongoing investigation into dogs developing the dilated cardiomyopathy (DCM), a serious heart disease, which appears to be associated with the use of grain-free or exotic protein diets. The agency has received reports of 560 dogs and 14 cats with DCM, and of these 199 dogs and 5 cats have died from the condition.

The agency has also released a list of all the diets being fed to these pets:

Brands reported fed in at least 10 reported cases of DCM: 

The specific relationship between diet and DCM in these cases is not yet understood, so it is impossible to say if the food is a primary cause of DCM and, if so, how this is happening. However, the common thread among the diets involved seems to be the use of legumes or pulses (e.g. peas, lentils) in place of grains in the diet.

While many of the diets contain common protein sources (e.g. chicken and lamb), a surprisingly high proportion have unusual and uncommon meats as their main protein source. Again, the significance of this is not yet clear.

There is a concentration of cases among golden retrievers, though dogs of many other breeds have been affected as well.

Further data collection and research will be necessary to determine the precise relationship between diet and DCM in these cases. There are likely multiple factors involved, including the ingredients in the diet, the genetics or particular breeds and individuals, and others we may not yet know about. Pet owners feeding these diets don’t need to panic, since far more dogs on these diets do NOT have DCM than do. However, if you are feeding one of these foods, or a diet similar in composition, and especially if you are feeding this to a golden retriever, it would be a good idea to talk to your vet about screening your pet for DCM and considering a change in diet.