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6-Step Guide to Better Nutrition and Weight Management Conversations

Updated 2021 AAHA Spay & Neuter Nutrition Guidelines

Donna M. Raditic, DVM, DACVIM (Nutrition), Board Certified Veterinary Nutritionist, Athens, GA

Updated 2021 AAHA Spay & Neuter Nutrition Guidelines


The American Animal Hospital Association (AAHA) has recently released its 2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats. The new guidelines go beyond the 2014 version, which primarily addressed assessment and weight management to be “truly a comprehensive approach to dietary management in primary care companion animal practice.” It is a 26-page document that includes the nutrition basics (e.g. nutritional assessment, body condition score, muscle condition score and individualized nutritional recommendations.) Other nutrition topics that are included are disease specific diets/ingredients, diet-associated dilated cardiomyopathy, home-prepared diets, raw protein diets, age and breed specific diets, as well as microbiome, probiotics and prebiotics. The bulk of the guidelines discusses the complex topic of communicating with clients, with emphasis on approaches for effective, nonjudgmental communication of dietary recommendations to clients and strategies to increase client compliance.

Nutrition conversations have three aspects.

First is the content, meaning the scientific or medical knowledge that informs a complete and balanced nutrition recommendation. Second is the process or the approach to engage the client in a discussion about the pet’s nutrition. Finally, there is the perceptual aspect of communications, in other words, how the client thinks and feels about pet nutrition. Veterinarians prefer to focus on content, but successful nutrition discussions are about the process, and even more importantly the perceptions clients have about pet nutrition. Understanding the perceptual aspects – what the client believes and perceives, their goals and ideas which must be heard, identified and acknowledged is critical to have successful nutrition discussions and outcomes.

Successful nutrition discussions mean providing two separate recommendations.

The first is the nutrition-related healthcare decision i.e. a nutrition change is recommended to manage the health of the pet proactively or to address a nutrition-related health concern. The second recommendation is a product-specific commercial diet to support the nutrition-related health care decision. Often veterinarians are uncomfortable or fail to recommend specific diets. Interestingly, a recent survey of pet owners concluded that when a pet’s diet is discussed in the context of a pet’s health, the veterinarian consulting during a wellness appointment may be most persuasive to the owner for changing their pet’s diet.1 This survey tells us that veterinarians should feel confident that pet owners are receptive to recommendations regarding a pet’s diet, especially when the recommendation is made in the context of their pet’s health.  

The 2021 guidelines provide a step-by-step approach to making a nutrition recommendation to clients as follows:

  1. How to initiate a nutrition-related healthcare recommendation
  2. Exploring with the owner all nutrition and non-nutrition options
  3. Client education about benefits and risks of each nutrition option
  4. Make a clear nutrition-related recommendation
  5. Check in with the client to get feedback and to see how information was received
  6. Plan appropriate follow up with the client once dietary change has been implemented


We can use these steps to help veterinarians communicate with clients about the need for specialized nutrition for spayed and neutered cats and dogs. As spay and neutering is a risk factor for overweight/obesity and 85% of dogs and 93% of cats in the United States are spayed or neutered2, it seems that spay/neuter nutrition recommendations to clients should be happening on a regular basis. As currently in the US more than 56% of dogs and 60% of cats are either overweight or obese3, it is evident veterinarians are either not having this important nutrition conversation or that their communication is unsuccessful. This is a problem as it has been reported that with no dietary intervention post-neutered dogs and cats can have a 30% and 21% increase in body weight respectively4,5. Furthermore, these weight gains are typically seen 5 to 6 months post spay or neuter. 

So let’s apply the 2021 AAHA guidelines to this most important spay neuter nutrition-related health concern – the need to prevent overweight/obesity in the spayed or neutered (S/N) veterinary patient. First the content or medical knowledge that informs a complete and balanced nutrition recommendations should include the fact that although S/N has benefits, we do know that the spayed and neutered dogs have 2x the risk of becoming obese while cats have 3x the risk of becoming obese6,7. Removing sex hormones has two impacts on the S/N patient that plays a role in this increased risk for overweight/obesity4

  1. There is a decrease in metabolic rate which leads to the S/N pet having a reduced daily caloric requirement.9
  2. Appetite is increased post spay and neuter.4

This decrease in metabolic rate has been documented and means we need to consider about a 30% decrease in daily caloric requirement for the S/N dog and 24% decrease for the S/N cat.8,9 Meanwhile post S/N there can be a 60% increase in the appetite in the dog and a 23% increase in in the appetite of the cat8-10. These physiological changes that occur in the S/N pet creates the perfect storm – we have a S/N patient with an increase in appetite that needs to consume fewer calories. 


Recall successful nutrition discussions mean providing two separate recommendations. Here the first recommendation is the nutrition-related healthcare decision – we know that when we spay or neuter a pet it now has a higher risk of becoming overweight/obese; therefore, a nutrition change is essential to prevent weight gain in the S/N patient. The second recommendation is a product specific commercial diet to support the nutrition-related health care decision. Currently, we do not have commercial diets formulated specifically for the S/N dog and cat. Based on the scientific literature and as discussed for weight management in the guidelines, an appropriate S/N diet would have the following features:  

  1. Complete and balanced ingredients that are appropriate for the life stages- growth, growth of a large breed and adult maintenance 
  2. Veterinary exclusive with easily accessible nutrient profile (similar to a veterinary therapeutic diet)
  3. High protein digestibility to provide essential amino acids for proper growth and development or lean body mass 
  4. High protein and fiber to promote a satiety effect 
  5. Moderate to restricted energy density i.e. kilocalories/kilograms   


Now let’s use the 2021 AAHA step-by-step approach to learn how veterinarians and their team can make spay/neuter nutrition recommendations to clients.

1. Initiate a nutrition-related healthcare recommendation. 

This is now easy because spaying and neutering are two surgical procedures that every veterinarian understands and although controversy may exist about ideal age, veterinarians routinely discuss the S/N procedures with clients. With every discussion about spaying or neutering, veterinarians and their team can initiate the nutrition-related healthcare recommendation by stating, “While we are talking about the S/N surgery, we want you to be aware removal of sex hormones can increase the risk for overweight/obesity. Let me explain to you why that happens and what we need to do to prevent your pet from becoming overweight or even obese”.

2. Exploring with the owner all nutrition and non-nutrition options. 

Once clients are aware their S/N pet may be at risk for overweight/obese, they may want to reconsider the timing of the S/N surgery or if S/N is truly necessary. Fortunately, veterinarians are well versed in the why, why not, and when of S/N surgery and will easily be able to provide best health care options for the client and their pet. 

3. Client education about benefits and risks of each nutrition option. 

The conversation here may include expanding on the content discussed above for the S/N patient i.e. risk for obesity increases due to the need to reduce daily caloric intake and increase in appetite. If we don’t change the diet and feeding plan for the S/N pet they can quickly become overweight which becomes the steppingstone to obesity. The veterinarian and team can discuss the problems and expense that can occur if a nutrition change is not instituted, and the S/N pet becomes overweight/obese, including financial impacts such as more vet visits due to other obesity related disease and increased costs of preventatives and medications for the overweight/obese pet. A conversation about the research showing overweight/obese pets not only have more health issues, but they can have a shorter life span is also important. 

4. Make a clear, nutrition-related recommendation. 

Tell clients you and your team are committed to a proactive S/N nutrition program that will prevent their pet from becoming overweight and/or obese post S/N procedure. Veterinarians and their team should reiterate the benefits of using proactive S/N nutrition. You can let clients know you will recommend an appropriate S/N diet to prevent overweight/obesity. Discuss the features of the S/N diet and assure them you will have written instructions on how to transition to the new diet and exact feeding instructions using a gram scale. It will be a personalized nutrition plan for each S/N patient, but it will clearly assure your clients they will have the team’s support now and going forward to prevent their S/N pet from becoming overweight or obese.

5. Check in with the client to get feedback and to see how information was received.

Because the nutrition recommendations are related to the health of the S/N pet, clients will most likely appreciate the proactive nutrition changes. Still it may be beneficial to say, “We know it takes a team to keep our pets from becoming overweight/obese and we want you to know we will be here every step of the way” and then asking the client, “Does this all make sense to you? Do you have any questions or concerns that we have not addressed?” 

6. Plan appropriate follow up with the client once dietary change has been implemented.

A member of the veterinary team should follow up with the client in a couple of days to ensure the diet transition is going well. Telemedicine rechecks can be a useful way to troubleshoot and ensure successful implementation of your proactive S/N nutrition program.  

There are a few other points that will help to ensure successful spay/neuter nutrition recommendation to clients. 

At every visit, the veterinary team should be sure the pet is weighed on the same scale and demonstrate to the client how to do body condition score. Both body weight and body condition score are recorded and should be shown to and discussed with the client. This demonstrates to clients the tools we use in weight management programs and reinforces the importance of proper diet and feeding plans.

Spay/neuter discussions are a true opportunity for veterinarians and their team to develop effective communication of dietary recommendations to clients and strategies to increase client compliance.

Clients have many concerns about spay/neuter surgery. They worry about anesthesia, post-operative care, needed follow up, etc. and yes, they will be receptive and want to understand how S/N can affect the nutritional needs of their beloved pet. During those conversations, the client is present, attentive, listening carefully – the bond of trust between the veterinarian and the client is at its peak. Using the step-by-step process from the 2021 AAHA guidelines to guide client conversations about spaying and neutering as a nutrition-related healthcare issue will allow the veterinarian to make nutrition and diet recommendations that are successful. Furthermore, communicating the need for a proactive S/N nutrition program requires a team approach that immediately includes the client, and this will translate to lifelong weight management for the S/N veterinary patient.


  1. Alverez EE, Schultz KK. Effect of personal, food manufacturer, and pet health statements during a pet wellness appointment on a dog or cat owner’s decision to consider changing their pet’s diet. J Am Vet Med Assoc. 2021 Sep 15;259(6):644-650.

  2. APPA 2017-2018 https://wsvma.org/2020/02/14/pet-obesity-at-epidemic-proportions/#:~:text=The%20prevalence%20of%20overweight%20and,nationwide%20in%202018%20were%20overweight

  3. Jeusette et al; Effect of ovariectomy and ad libitum feeding on body composition, thyroid status, ghrelin and leptin plasma concentrations in female dogs* J Anim Physiol Nutr (Berl). 2006 Feb;90(1-2):12-18

  4. Wei et al; Early Effects of Neutering on Energy Expenditure in Adult Male Cats: PLoS One. 2014 Feb 26;9(2):e89557.

  5. Lefebvre, S.L.; Yang, M.; Wang, M.; Elliott, D.A.; Bu, P.R.; Lund, E.M. Effect of age at gonadectomy on the probability of dogs becoming overweight. J. Am. Vet. Med. Assoc. 2013, 243, 236–243.

  6. Nguyen P., Dumon HJ, et al. Effects of dietary fat and energy on body weight and composition after gonadectomy in cats. Am J Vet Res. 2004 Dec;65(12):1708-1713

  7. Jeusette, I.; Detilleux, J.; Cuvelier, C.; Istasse, L.; Diez, M. Ad libitum feeding following ovariectomy in female Beagle dogs: Effect on maintenance energy requirement and on blood metabolites. J. Anim. Physiol. Anim. Nutr. 2004 Apr;88(3-4):117-121.

  8. Kanchuk et al; Weight gain in gonadectomized normal and lipoprotein lipase-deficient male domestic cats results from increased food intake and not decreased energy expenditure Nutrient Metabolism 2003 American Society for Nutritional Sciences 1866-1874.

  9. llaway D, Gilham M, Colyer A, et al. (2017) The impact of time of neutering on weight gain and energy intake in female kittens. J Nutr Sci 6, e19.

  10. Kanchuk et al; Neutering Induces Changes in Food intake, body weight, plasma insulin and leptin concentrations in normal and lipoprotein lipase-deficient male cats J Nutr. 2002 Jun;132 (6 Suppl 2):1730S-1732S.