Debunking common diet myths and misinformation

Veterinarians and their staff are often approached by clients with questions about pet nutrition, including “fad” topics. While specific issues surrounding these trends may change over time, concepts remain the same. Facts may be misunderstood, distorted, or just made up, to create believable stories about nutrition, food, or supplements for pets. Many can be so believable they incite emotional connections to these issues.

Clients with sick pets can be especially vulnerable to anecdotes that “promise” a “cure.” These stories are promoted and distributed by word-of-mouth and social media until they become pervasive. Equip your team with guidelines and resources to help address misinformation.

Taking a general approach

Pet owners and veterinarians are all susceptible to the impacts of misinformation or distorted information that lead to misunderstandings when taken out of context. Other clients may just have questions about potentially legitimate issues in pet care and nutrition, where veterinarians remain the number one resource. Despite competition from social media, how can you, as a veterinarian, remain confident in your ability to address the plethora of questions coming your way?

There are two very different aspects to consider: the factual aspects and the emotional aspects. If a client is simply asking for information about a topic or claim, this is perhaps easier to tackle. Addressing emotional aspects can be more challenging. It is important to remain nonjudgmental and assume the client has the pet’s best interests in mind. Listen to concerns being raised and ask questions to better understand the client’s priorities and their decision-making process. Ideally, you will be able to help them understand how the facts (most myths have some factual basis) have been distorted and help them correctly interpret the facts. Providing clients with reliable sources for pet nutrition information may be useful. as well. (See “A bit for everyone.”)

A bit for everyone!

Resource materials and references for pet owners and veterinary teams about pet nutrition, nutritional assessments, and conversations about nutrition.

Resources for pet owners
	National Research Council: Your Dog’s Nutritional Needs
	National Research Council: Your Cat’s Nutritional Needs
	World Small Animal Veterinary Association Nutrition Guides for Cat and Dog Owners
Resources for veterinary practices
	World Small Animal Veterinary Association Global Nutrition Toolkit
	World Small Animal Veterinary Association Global Nutritional Assessment Checklist
	Pet Nutrition Alliance
	Purina Institute CentreSquare Nutritional Conversations
	Purina Institute CentreSquare
	TUFTS Petfoodology
	TUFTS Clinical Nutrition Service – Resources
	Petfood Institute
Resources to find boarded veterinary nutritionists
	Veterinary Specialists DirectoryVeterinary Specialists Directory
	Board-Certified Veterinary Nutritionist Sortable Directory

The role of a nutritional assessment

One important tool to help you remain confident in the quality of foods you sell or recommend is to routinely perform nutritional assessments on all your patients. Following the World Small Animal Veterinary Association (WSAVA) guidelines for screening assessment is fast and helps identify patients that may need further evaluation.¹

It is likely you will find few diet-related issues when patients are fed nutritionally balanced diets appropriate to their needs (based on species, life stage, lifestyle, and overall health). However, you may see patterns of concern among patients fed other foods (commercial or otherwise) or supplements. These patterns can help you feel confident in the foods while flagging those products you may wish to avoid or recommend against. This knowledge and experience will help you talk with clients about nutrition fads and help direct them to more appropriate foods or supplements, when needed.

Tips to find and share factual information There are many sources of pet nutrition information, but not all are equally factual. How can you, as a veterinarian, judge sources so that you are confident in the information? Here are a few tips: Consider the source. Is the information provided by ACVIM or ECVCN boarded veterinary nutritionists, or PhD nutritionists with training in canine or feline nutrition? If not, consider the qualifications of the person or group providing the information. Consider the goal. Is the information provided promoting or denigrating commercial products? If so, what support is provided for the claims. Do the claims seem believable (consider false claims sometimes can be more believable than truth)? Are the claims preying on emotions? Consider the scientific support. Are the claims or information based on peer-reviewed publications from high-quality journals? If not, are there scientific studies with enough information provided that you could determine the quality of the data? Is the support simply based on testimonials or personal experience, or even lacking completely? Consider the likelihood of factual truth. Does the claim make sense based on your understanding of animal physiology, or based on good business practices (e.g. do pet food companies really intend to kill pets?)?

Current nutritional myths and trends

Raw food diets
Pet owners who feed raw foods express attitudes about food processing and pet nutrition that differ, on average, from those who feed commercial cooked foods. For example, those feeding raw foods were significantly more likely to agree with the statements, “Dogs (or cats) are carnivores, so they need a meat-based diet,” and “Cooking destroys nutrients in pet foods. They also were more likely to believe feeding raw is healthier and more natural than cooked foods, and raw foods are safer and provide better nutrition than commercial foods.² These beliefs, however, have not been scientifically proven. There are a few published controlled trials objectively evaluating the benefits of raw diets, but numerous studies demonstrate potential risks from such diets. Clients may not be aware of potential risks of feeding raw or undercooked animal products. As a healthcare provider, the veterinarian plays an important role ensuring clients have access to objective science-based information to help them make informed decisions for their pet.

Similar to cooked foods, commercial or homemade raw diets can provide complete and balanced nutrition if properly formulated. However, even nutritionally balanced raw bones and meat diets can introduce potential risks to both the pet and owner, including damage or obstruction within the alimentary canal from bones, and potential exposure to pathogens.³ Numerous reports of Salmonella contamination and/or outbreaks of Salmonellosis have been linked to uncooked pet foods and treats. A much higher proportion of commercial raw pet foods tested positive for Salmonella or Listeria, compared to dry commercial diets.⁴

Even the use of meats intended for human consumption is associated with risk from bacterial contamination. Parasites also can be spread from raw food diets. Dogs consuming raw foods are more likely to shed Salmonella spp and other potential pathogens than those fed cooked, commercial dry foods, even if they remain healthy.^5,6 This poses a zoonotic risk for the human population, especially those who are immunocompromised.

It is important to discuss and document the risks of feeding raw diets with pet owners who choose this option. It is highly recommended these clients be referred to an American College of Veterinary Internal Medicine (ACVIM) (Nutrition)- or European College of Veterinary and Comparative Nutrition (ECVCN)-boarded veterinary nutritionist for advice on nutritionally balanced and safe raw food diets and receive guidelines for safe food handling.

Pet owners who opt to feed commercial raw foods should contact the pet food manufacturer to inquire about pathogen mitigation methods and the company’s quality assurance program.

Grain-free diets
Some owners and veterinarians are concerned about the use of grains in pet food, referring to them as non-nutritional “fillers” or raising concerns about “excess” carbohydrates in dry pet food. The basis for this appears to be driven, at least in part, by negative marketing and misperceptions about gluten. In fact, whole grains are an excellent source of digestible carbohydrates as well as dietary fiber, essential amino acids, essential fatty acids, and other nutrients.

Numerous studies have documented health benefits associated with greater consumption of whole grains in humans.⁷ The majority of studies reporting adverse effects from dietary carbohydrates are based on excess sugar consumption.⁸ Such studies are not relevant to commercial pet foods which generally provide complex carbohydrates and starch rather than simple sugars.

Both dogs and cats are easily able to digest properly cooked carbohydrates, with an efficiency greater than 90 percent.^9,10 Carbohydrates provide a source of glucose, the energy source required by most of the cells in the body.

In response to the unfounded, but widespread concerns about grains, several pet food companies introduced grain-free pet foods, which have increased in market share to constitute about 40 percent of the dry dog food market in the U.S.¹¹ These foods may not be any lower in carbohydrates compared to grain inclusive formulations, but instead are formulated with alternate sources of carbohydrates, such as potatoes or pulses (e.g. peas, lentils, chickpeas). One survey showed grain-free foods were more likely to be purchased by pet owners who obtain pet food information from online resources or pet store staff.¹¹

In the years since grain-free pet foods have become widely available, an association has been noted between consumption of these foods, especially those high in pulses, and diet-associated canine dilated cardiomyopathy (dDCM).^12,13 While no direct cause has been established, and investigations have not provided scientific confirmation of a cause-effect relationship,^14,15 research in this area is ongoing. Veterinarians can inform pet owners about this complex issue and ongoing research so they can make an educated decision for their pet.

Summary

Due to the abundant sources of misinformation about pet nutrition, veterinarians will always be challenged to address misconceptions about varying topics. Trending topics of today will be replaced by new ones in the future, but the principles for addressing these remain the same: find reliable resources for accurate information; stay up to date; conduct nutritional assessments with good dietary histories on all patients; understand the client’s perspective and remain open and available to your clients to discuss nutrition topics.

As a veterinarian, you have the basic science and clinical training, plus the experience to assess the validity of information presented to you. In addition, as the primary care veterinarian, you have firsthand knowledge of the pet and the trust of the client, who knows you share their goal of ensuring their pet lives a healthy long life.

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Dottie Laflamme, DVM, PhD, DACVIM (Nutrition) is a retired veterinary nutritionist, having worked in the research department of Ralston Purina and Nestle Purina for nearly 30 years. Her research focused on therapeutic nutrition and nutrition for aging cats and dogs.

Laura Eirmann, DVM, DACVIM (Nutrition), is currently the clinical nutritionist at the Oradell Animal Hospital in Paramus, N.J.

References

1. Freeman LM, Becvarova I, Cave N, et al. Nutritional assessment guidelines. J Small Anim Pract 2011;52:385-396. doi: 10.1111/j.1748-5827.2011.01079.x. Epub 2011 Jun 7
2. Morgan SK, Willis S, Shepherd ML. Survey of owner motivations and veterinary input of owners feeding diets containing raw animal products. PeerJ 2017;5:e3031
3. Freeman LM, Chandler ML, Hamper BA, Weeth LP. Current knowledge about the risks and benefits of raw meat-based diets for dogs and cats. J Am Vet Med Assoc 2013;243:1549-1558.
4. FDA.The pet food study. Get the Facts! Raw Pet Food Diets can be Dangerous to You and Your Pet | FDA Accessed June 2024
5. Lefebvre SL, Reid-Smith R, Boerlin P, Weese JS. Evaluation of the risks of shedding Salmonellae and other potential pathogens by therapy dogs fed raw diets in Ontario and Alberta. Zoonoses Public Health. 2008 Oct;55(8-10):470-80.
6. Runesvärd E, Wikström C, Fernström LL, Hansson I. Presence of pathogenic bacteria in faeces from dogs fed raw meat-based diets or dry kibble. Vet Rec. 2020 Oct 31;187(9)
7. Lafiandra D, Riccardi G, Shewry PR. Improving cereal grain carbohydrates for diet and health. J Cereal Sci 2014;59:312-326.
8. Gillespie KM, Kemps E, White MJ, Bartlett SE. The impact of free sugar on human health – a narrative review. Nutrients 2023;15:889 https://doi.org/10.3390/nu15040889.
9. Carciofi AC, Takakura FS, de-Oliveira LD, et al. Effects of six carbohydrate sources on dog diet digestibility and post-prandial glucose and insulin response. J Anim Physiol Anim Nutr 2008;92:326–336.
10. de-Oliveira LD, Carciofi AC, de-Oliveira MCC, et al. . Effects of six carbohydrate sources on diet digestibility and post-prandial glucose and insulin responses in cats. J Anim Sci 2008; 86:2237-2246.
11. Banton S, Baynham A, Pezzali JG, et al. Grains on the brain: A survey of dog owner purchasing habits related to grain-free dry dog foods. PLoS ONE. 2021; 16: Doi: e0250806. https://doi.org/10.1371/journal.pone.0250806
12. Freeman LM, Stern JA, Fries R, et al. Diet-associated dilated cardiomyopathy in dogs: what do we know? J Am Vet Med Assoc 2018;253:1390-1394.
13. Smith CE, Parnell LD, Lai C-Q, Rush JE, Freeman LM. Investigation of diets associated with dilated cardiomyopathy in dogs using foodomics analysis. Sci Rep. 2021; 11:15881.
14. McCauley SR, Clark SD, Quest BW, et al. Review of canine dilated cardiomyopathy in the wake of diet-associated concerns. J Anim Sci 2020;98:1-20. Doi: 10.1093/jas/skaa155.
15. Quest BW, Leach SB, Garimella S, et al. Incidence of canine dilated cardiomyopathy diagnosed at referral institutions and grain-free pet food store sales: a retrospective survey. Frontiers Anim Sci 2022; 3: Doi: 10.3389/fanim.2022.846227.