Supplements for homemade dog food: what the research says is usually missing

When researchers at the University of California, Davis ran 200 home-prepared dog food recipes through nutritional analysis, 190 of them had at least one essential nutrient below published guidelines [1]. So "dog supplements for homemade food" is a sensible thing to search for, but the published work cited here describes a recipe formulation problem, not a shopping list.

The short answer

• "Complete and balanced" on a label means a food is intended to be fed as a pet's sole diet and should be nutritionally balanced; the US Food and Drug Administration says this is shown against AAFCO nutrient profiles or by a feeding trial [4].
• In a 2013 analysis of 200 home-prepared recipes for adult dogs, 95% had at least one essential nutrient below NRC or AAFCO guidelines. This was mostly a computer analysis of written recipes, not a study of dogs eating them [1].
• Zinc, choline, copper, vitamin D, vitamin E, EPA plus DHA and calcium were the nutrients most often low in that recipe analysis [1]. A 2019 Brazilian laboratory analysis of 75 dog recipes, again of recipes and not of dogs, found calcium and potassium most often low [2].
• Excess matters too. The Merck Veterinary Manual describes skeletal problems in large-breed puppies given excess calcium, and soft tissue calcification with vitamin D toxicity [6][7].
• WSAVA's Global Nutrition Committee recommends that raw meat-based diets not be fed to dogs and cats [9].
• The 2013 authors recommended that recipes "be obtained from or evaluated by board-certified veterinary nutritionists or veterinarians with advanced training in nutrition" [1]. The Merck manual's owner edition recommends a high-quality commercial food, or one designed by a credentialed veterinary nutritionist [7].

What does "complete and balanced" mean?

"Complete and balanced" is a labelling term for a food that is intended to be fed as a pet's sole diet and should be nutritionally balanced, according to the US Food and Drug Administration [4]. The FDA describes two ways a product can substantiate the wording: by meeting one of the AAFCO Dog or Cat Food Nutrient Profiles, or by passing a feeding trial using AAFCO procedures [4]. AAFCO, the Association of American Feed Control Officials, has established two profiles for dogs, one for growth and reproduction and one for adult maintenance [4].

Europe has an equivalent reference. FEDIAF, which represents the European pet food industry, publishes nutritional guidelines for complete and complementary pet food. It describes them as a review of National Research Council (NRC) data and other science, peer reviewed by independent veterinary nutritionists [5]. In Australia, the RSPCA Knowledgebase says any food offered to dogs should meet the Australian Standard for the manufacturing and marketing of pet food, AS 5812, or an equivalent international standard confirmed through third-party independent audits, or be prepared using human-grade ingredients [11].

The FDA also notes that treats, snacks and supplements are typically not intended to be a pet's sole diet, so they are often not complete and balanced [4].

What have analyses of homemade dog food recipes found?

Three published analyses are summarised below. Each compared recipes with nutrient guidelines. Neither of the two papers read in full fed the diets to dogs or measured health outcomes, and the abstract of the third reports none.

Stockman and colleagues, 2013 (University of California, Davis)

• What was analysed: 200 recipes for home-prepared maintenance diets for adult dogs, from 34 sources. Of these, 133 came from two veterinary textbooks and nine pet care books, and 67 from 23 websites [1].
• Who wrote them: 129 recipes (64.5%) were written by veterinarians and 71 (35.5%) by non-veterinarians [1].
• Method: computer-based nutritional analysis of every recipe, with laboratory verification of selected nutrients in 15 of them [1].
• Result: 190 of 200 recipes (95%) had at least one essential nutrient below NRC or AAFCO guidelines [1]. Nine recipes exceeded all the AAFCO minimums for adult dogs, and three met or exceeded every NRC recommended allowance [1].

The nutrients most often low were zinc (69% of recipes), choline (64.5%), copper (54%), EPA plus DHA (53.5%) and calcium (35%) [1]. Among the recipes where the vitamins could be assessed, 102 of 167 were too low in vitamin D and 79 of 175 were too low in vitamin E [1].

Pedrinelli and colleagues, 2017 (Brazil)

This study assessed 106 home-prepared diet recipes published in Portuguese: 80 for dogs, 24 for cats and two for both species [3]. Every diet had at least one nutrient below recommendations [3]. Among the dog recipes, 82.9% were below recommendations for vitamin E, 75.6% for zinc and 68.3% for iron [3]. Only the abstract could be read for this article, so the method and limits of this study are not described here.

Pedrinelli and colleagues, 2019 (Brazil)

Recipes for healthy adult dogs (75) and cats (25) were prepared and chemically analysed for protein, fat, fibre, minerals and heavy metals. Nutrient levels were compared with NRC and FEDIAF recommendations, and heavy metals with the FDA's maximum tolerable levels [2]. None of the diets supplied recommended levels of all the nutrients evaluated, and more than 84% had three or more nutrients below recommendations [2]. In the dog recipes, calcium and potassium were the nutrients most often low [2].

On homemade dog supplements specifically: 15 of the 75 dog recipes listed a vitamin-mineral supplement as an ingredient, and 14 of those did not specify a manufacturer or product. Forty of the 75 did not indicate any supplementation of minerals, amino acids or vitamins [2].

Why does calcium-to-phosphorus balance matter?

Calcium and phosphorus are in close balance with one another in the body. The Merck Veterinary Manual states that dietary phosphorus levels are often governed by calcium levels, with the goal of the right ratio for each species, size and life stage [6]. The same reference gives the AAFCO minimum and maximum calcium-to-phosphorus ratios for dogs as 1:1 to 2.1:1 [6].

Merck notes that calcium deficiencies have occurred with high-meat or all-meat diets, which are high in phosphorus and low in calcium, and it associates insufficient calcium or excess phosphorus with nutritional secondary hyperparathyroidism [6]. That passage covers small animals generally, not dogs alone. Merck's dog owner edition says that animals fed all-meat diets commonly develop rickets [7]. In the 2019 Brazilian analysis, 11 of the 75 dog recipes (14.7%) had a calcium-to-phosphorus ratio above 2:1 [2].

Can you over-supplement a homemade diet?

Yes. Veterinary references document harm from excess as well as from deficiency.

• Calcium in growing large-breed puppies. Merck reports that excessive calcium supplementation (above 3% calcium on a dry-matter basis) causes more severe clinical signs of osteochondrosis and decreased skeletal remodelling in young, rapidly growing large-breed dogs than diets with 1% to 3% calcium [6]. The owner edition adds that giant-breed dogs fed excess calcium are more likely to develop osteochondrosis and hypertrophic osteodystrophy [7].
• Vitamin D. Merck states that vitamin D toxicity causes high blood calcium and phosphorus with irreversible soft tissue calcification and can eventually be fatal. It says cases have been associated with excessive vitamin D inadvertently added to commercial pet foods and with rodenticides containing cholecalciferol [6].

Those figures describe the whole diet as analysed. They are not a guide to how much of anything to add, which is a question for a vet.

What about supplements for a raw diet?

People searching for the "best dog supplements for raw diet" are asking about nutrient balance. The bodies below raise a separate issue: contamination with pathogens.

• WSAVA. The Global Nutrition Committee recommends that raw meat-based diets not be fed to dogs and cats, and says home-made versions have a high risk for contamination with bacteria, parasites and other pathogens [9]. Its owner handout states there is no evidence that raw meat-based diets provide health benefits over commercial or balanced homemade cooked diets, that people in the household can be infected by handling the food or the pet's stools, and that freezing, dehydration or freeze-drying do not kill all bacteria in food [8].
• FDA. The Center for Veterinary Medicine says it is concerned about the public health risk of raw pet food diets. In a two-year study running from October 2010 to July 2012, it tested 196 samples of commercially available raw dog and cat food in the second year: 15 were positive for Salmonella and 32 for Listeria monocytogenes [10].
• RSPCA Knowledgebase. The Australian guidance says bones and raw meat are not recommended, and that raw bones carry bacteria that can make both animals and humans ill. For owners who do decide to feed raw meat or raw bones, it recommends choosing only human-grade products [11].

WSAVA's handout also says that home-prepared diets, cooked or raw, may have important nutrient deficiencies and excesses [8].

Who do the sources say should write the recipe?

Stockman and colleagues wrote: "We recommend that recipes for home-prepared diets for dogs be obtained from or evaluated by board-certified veterinary nutritionists or veterinarians with advanced training in nutrition" [1]. The Merck Veterinary Manual's owner edition says studies show many homemade diets for dogs are deficient in minerals and fail to achieve a proper calcium-to-phosphorus ratio, and recommends a high-quality commercial food or one designed by a credentialed veterinary nutritionist [7].

On what "board-certified" refers to: in a guide to assessing pet food manufacturers, WSAVA names a PhD in animal nutrition, or board certification by the American College of Veterinary Nutrition or the European College of Veterinary Comparative Nutrition, as appropriate qualifications for a company's nutritionist [12]. That guide is about commercial food makers, not about home recipes.

Your own vet is the place to start. For background on how these products are classified, see our guide to how dog supplements are regulated in Australia.

Foods that should never go in the bowl

The RSPCA Knowledgebase says the following substances should never be fed because they are toxic to dogs, and notes that this is not a complete list [11]:

• alcohol
• onions and onion powder
• garlic
• chocolate, coffee or caffeine products
• mouldy or spoiled foods, or compost
• avocado
• bread dough or yeast dough
• grapes, raisins and sultanas (including in Christmas cakes)
• currants
• nuts (including macadamia nuts)
• fruit stones or pits (such as mango seeds, apricot stones and avocado stones)
• mushrooms
• fruit seeds

Treat it as urgent if your dog eats any of these: contact your vet or the Animal Poisons Helpline on 1300 869 738 (Australia) immediately. Do not wait for signs to appear and do not try to treat it at home. The ASPCA Animal Poison Control Center's advice for a pet suspected of eating a hazardous food is to note the amount ingested and contact your veterinarian or a poison control service [13]. A second RSPCA Knowledgebase page, on household dangers, tells owners to contact their veterinarian immediately after suspected alcohol or xylitol ingestion, and points to the Australian Animal Poisons Helpline for anything toxic [14].

What the research does not tell us

• These were analyses of recipes. The two papers read in full did not follow dogs eating the diets, so they do not show how often a given shortfall leads to illness, or how quickly.
• The Brazilian recipes were published in Portuguese [2][3], and the 2013 paper drew on textbooks, pet care books and websites [1]. None of the three papers, as read for this article, describes its recipes as Australian.
• Neither of the two papers read in full tested whether adding a general-purpose supplement to an unbalanced recipe brings it up to a complete and balanced standard.
• No funding or conflict-of-interest statement was visible in the versions of the three papers that could be opened for this article, so none is reported here.

When to see your vet

• Before you start a home-prepared or raw diet, and before adding any supplement to one.
• If the dog is a puppy, or is pregnant or nursing. AAFCO has a separate nutrient profile for growth and reproduction, which covers growing, pregnant and nursing animals [4].
• If your dog seems unwell in any way while eating a home-prepared diet. That needs an examination, not a diet change at home.
• Immediately, if your dog has eaten a food on the toxic list above.

Which supplements a particular recipe needs is the question these analyses leave open. They counted how often recipes fell short, and the 2013 authors' recommendation was to have each recipe written or evaluated by the qualified people they named [1].

This article is general information, not veterinary advice. Speak to your vet before changing your dog's diet, supplements or medication.

References

1. Stockman J, Fascetti AJ, Kass PH, Larsen JA (2013). Evaluation of recipes of home-prepared maintenance diets for dogs. Journal of the American Veterinary Medical Association, 242(11), 1500–1505. https://avmajournals.avma.org/view/journals/javma/242/11/javma.242.11.1500.xml
2. Pedrinelli V, Zafalon RVA, Rodrigues RBA, Perini MP, Conti RMC, Vendramini THA, Balieiro JCC, Brunetto MA (2019). Concentrations of macronutrients, minerals and heavy metals in home-prepared diets for adult dogs and cats. Scientific Reports, 9, 13058. https://www.nature.com/articles/s41598-019-49087-z
3. Pedrinelli V, Gomes MOS, Carciofi AC (2017). Analysis of recipes of home-prepared diets for dogs and cats published in Portuguese. Journal of Nutritional Science, 6. Abstract record (abstract only read): https://agris.fao.org/search/en/providers/122436/records/67597979c7a957febdf82818
4. US Food and Drug Administration (content current as of 28 February 2020). "Complete and Balanced" Pet Food. https://www.fda.gov/animal-veterinary/animal-health-literacy/complete-and-balanced-pet-food
5. FEDIAF, European Pet Food (accessed 5 October 2026). Nutritional Guidelines. https://europeanpetfood.org/self-regulation/nutritional-guidelines/
6. Sanderson SL (reviewed November 2023, modified September 2024). Nutritional Requirements of Small Animals. Merck Veterinary Manual. https://www.merckvetmanual.com/management-and-nutrition/nutrition-small-animals/nutritional-requirements-of-small-animals
7. Grünberg W (reviewed March 2018, modified April 2026). Disorders Associated with Calcium, Phosphorus, and Vitamin D in Dogs. Merck Veterinary Manual, Dog Owners edition. https://www.merckvetmanual.com/dog-owners/bone-joint-and-muscle-disorders-of-dogs/disorders-associated-with-calcium-phosphorus-and-vitamin-d-in-dogs
8. WSAVA Global Nutrition Committee (undated). Raw Meat Based Diets for Pets. https://wsava.org/wp-content/uploads/2021/04/Raw-Meat-Based-Diets-for-Pets_WSAVA-Global-Nutrition-Toolkit.pdf
9. WSAVA Global Nutrition Committee (undated). Statement on Risks of Raw Meat-Based Diets. https://wsava.org/wp-content/uploads/2020/05/WSAVA-Global-Nutrition-Committee-Statement-on-Risks-of-Raw-Meat.pdf
10. US Food and Drug Administration (content current as of 22 February 2018). Get the Facts! Raw Pet Food Diets can be Dangerous to You and Your Pet. https://www.fda.gov/animal-veterinary/animal-health-literacy/get-facts-raw-pet-food-diets-can-be-dangerous-you-and-your-pet
11. RSPCA Knowledgebase (updated 21 August 2024). What should I feed my dog? https://kb.rspca.org.au/knowledge-base/what-should-i-feed-my-dog/
12. WSAVA Global Nutrition Committee (updated 2021). Selecting a Pet Food for Your Pet. https://wsava.org/wp-content/uploads/2021/04/Selecting-a-pet-food-for-your-pet-updated-2021_WSAVA-Global-Nutrition-Toolkit.pdf
13. ASPCA Animal Poison Control (accessed 5 October 2026). People Foods to Avoid Feeding Your Pets. https://www.aspca.org/pet-care/animal-poison-control/people-foods-avoid-feeding-your-pets
14. RSPCA Knowledgebase (updated 18 December 2023). What are common household dangers for pets? https://kb.rspca.org.au/knowledge-base/what-are-common-household-dangers-for-pets/