How Much Protein Do Senior Dogs Need? A Science-Based Guide

By Caroline Buck, Co-founder of Petaluma

Many pet parents notice their dog slowing down somewhere past age seven. The walks get shorter, and the back legs look a little thinner. For years, the standard advice was to cut protein as dogs aged to protect their kidneys. So how much protein does a senior dog need? Below, we cover how protein needs change with age, what the research recommends, when kidney disease changes the answer, and how Petaluma's recipes compare.

Why protein matters more as dogs age

Dogs lose lean muscle as they age, even when they are otherwise healthy. Veterinarians call this sarcopenia, which means age-related muscle loss (Freeman, 2012). Muscle supports mobility, balance, and immune function.

A lifelong study of Labrador Retrievers tracked this decline. Lean body mass held steady from ages 6 to 9, then declined steadily after the ninth year in dogs fed a standard amount (Lawler et al., 2008). A separate study found smaller back muscles in healthy older Labradors than in young ones (Hutchinson et al., 2012).

Older dogs also seem to use dietary protein less efficiently. In a classic study, older dogs needed about 50% more protein than young adults to maintain their body's protein reserves (Wannemacher and McCoy, 1966). That works out to about 3.75 grams of protein per kilogram of body weight each day, compared with 2.5 grams for young adults (Laflamme, 2005).

A dog can gain fat and lose muscle at the same time, so body weight alone may not show it (Freeman, 2012).

How much protein does a healthy senior dog need?

At least 25% of daily calories should come from protein for most healthy senior dogs. That figure comes from a review in Veterinary Clinics of North America, which states that diets meeting it "should meet the protein needs of most healthy senior dogs" (Laflamme, 2005). The same review concludes that protein restriction is unnecessary in healthy older dogs.

The 25% figure is a share of calories, which is different from the percentage printed on a bag. Foods with more fat pack more calories into each cup, so the same protein percentage can mean a different share of calories. Vets compare foods on a calorie basis or a dry-matter basis, which removes moisture so foods with different water content can be compared fairly.

The minimum protein level in the AAFCO adult maintenance profile is 18% on a dry-matter basis. AAFCO has no separate profile for senior dogs, so every complete senior food meets the adult maintenance profile. Our post on AAFCO nutrient profiles explains how those minimums work.

How much protein is in Petaluma's senior formula?

Lab testing of three recent batches measured 29.1% protein in Petaluma's senior formula, or 31.6% on a dry-matter basis. That is about 32 grams of protein per cup, and 29% of the formula's calories (Petaluma nutritional analysis, 2026). The guaranteed analysis on the bag lists 26.5% as the minimum. A guaranteed analysis is a conservative floor printed on the label, while the lab results show what each batch actually contains.

The protein in Petaluma's baked food is also highly digestible. University testing measured our protein sources at 93% digestible, compared with the lab's average of about 89% for animal protein in dry dog food (Vet Q&A with Petaluma's formulators). The senior formula is formulated by veterinary nutritionists and adds glucosamine, curcumin, and DHA for aging joints and brains. Our adult vs. senior comparison covers those additions in detail.

When kidney disease changes the answer

Chronic kidney disease (CKD) is the main reason a vet may recommend less protein for an older dog. CKD is diagnosed in well under 1% of dogs seen in general practice. A study of more than 107,000 dogs in UK practices estimated its prevalence at 0.37% (O'Neill et al., 2013). Risk rises sharply with age, and dogs 12 and older had about 5.5 times the odds of a diagnosis compared with dogs aged 7 to 12.

In a randomized trial of 38 dogs with CKD, those fed a renal diet had fewer uremic crises and lower mortality than dogs fed a standard adult diet (Jacob et al., 2002). A uremic crisis is a sudden buildup of waste products the kidneys can no longer clear. Renal diets are lower in phosphorus and protein than standard adult foods. Your vet will recommend targets based on your dog's bloodwork and the stage of disease.

Plant protein and phosphorus: what human research shows

The source of protein may matter as well as the amount. In people with CKD, one week of a vegetarian-protein diet led to lower blood phosphorus than a meat-based diet with matched nutrients (Moe et al., 2011). The researchers concluded that the protein source of phosphorus affects how the body handles it.

This was a small study in humans, and similar studies have not yet been done in dogs. Research on diet and chronic disease in dogs is much less developed than in human health. Until more canine studies exist, veterinary nutrition often draws on human research to make the best recommendation it can.

Comparing Petaluma's three recipes for early kidney changes

None of Petaluma's recipes is a prescription kidney diet. If your dog shows early signs of CKD, start with the protein and phosphorus targets your vet recommends. If your vet supports a non-therapeutic diet, the Whole Food Mixer is the closest fit of our three recipes. It has about half the phosphorus per calorie of our baked recipes, along with the lowest sodium and protein.

Sources: Petaluma nutritional analyses for the adult baked recipe (2026), senior baked recipe (2026), and Whole Food Mixer (2025). Phosphorus per 1,000 calories is calculated from each report.

Dogs with advanced kidney disease usually need a prescription renal diet. Our guide to managing chronic kidney disease in dogs covers the stages and what each one means for diet.

Can plant protein meet a senior dog's needs?

Yes, when the food is complete and balanced. Dogs need specific amino acids, not specific ingredients. Soy is a complete protein on its own. Peas and chickpeas each run low in certain amino acids, so recipes combine them with grains to supply the full set.

Peer-reviewed research supports well-formulated plant-based diets for adult dogs. In a year-long study, 15 healthy adult dogs aged 1 to 11 ate a commercial plant-based diet. The dogs maintained their health on physical exams, bloodwork, and amino acid and vitamin testing (Linde et al., 2024). A survey of more than 2,500 dog guardians also found fewer reported health disorders in dogs on nutritionally sound vegan diets (Knight et al., 2022). Studies focused only on senior dogs are still limited.

Signs your senior dog's diet may need adjusting

These changes are worth raising with your veterinarian at your dog's next checkup:

• Muscle loss: Your dog's spine, hips, or shoulders feel bonier, even though their weight looks normal.
• Weight change: Your dog gains or loses weight on the same portion.
• Lower energy: Your dog tires sooner on walks or has more trouble getting up.
• Appetite change: Your dog eats noticeably more or less than usual.
• New diagnosis: Your vet finds kidney, liver, or other changes in your dog's bloodwork.

If your dog's portion needs adjusting, our guide to how much to feed a senior dog walks through calorie needs by weight. For more on how our senior recipe was designed, read our Q&A with Dr. Blake Hawley, DVM.

Frequently asked questions

How much protein should a senior dog eat?

For most healthy senior dogs, at least 25% of daily calories should come from protein, according to a veterinary review by Laflamme (2005). Dogs with kidney disease or other conditions may need a different target, which your veterinarian can set.

Should I reduce protein as my dog gets older?

Not if your dog is healthy. A veterinary review concluded that protein restriction is unnecessary in healthy older dogs (Laflamme, 2005). Older dogs may need more protein than young adults to maintain their muscle.

Should I reduce protein if my senior dog has kidney disease?

Often yes, under your vet's guidance. Renal diets are lower in phosphorus and protein. In a randomized trial, dogs with kidney disease fed a renal diet had fewer uremic crises and lower mortality (Jacob et al., 2002). Your vet will set targets based on your dog's bloodwork and stage of disease.

How can I tell if my senior dog is losing muscle?

Feel along your dog's spine, hips, and shoulders. Bones that feel more prominent than before can signal muscle loss, even if your dog's weight is normal. Fat gain and muscle loss can happen at the same time, so body weight alone can miss it (Freeman, 2012).

Can a plant-based diet give a senior dog enough protein?

Yes, when the food is complete and balanced. In a year-long study, adult dogs fed a commercial plant-based diet kept normal bloodwork and nutrient levels (Linde et al., 2024). In lab testing, 29% of the calories in Petaluma's senior formula come from protein.

How much protein is in Petaluma's senior formula?

Lab testing of three recent batches measured 29.1% protein, or 31.6% on a dry-matter basis, which is about 32 grams per cup. The guaranteed analysis on the bag lists 26.5% as the minimum. Full results are in the senior formula's nutritional analysis.

References

1. Laflamme DP. Nutrition for aging cats and dogs and the importance of body condition. Veterinary Clinics of North America: Small Animal Practice. 2005;35(3):713-742. doi:10.1016/j.cvsm.2004.12.011. pubmed.ncbi.nlm.nih.gov/15833567
2. Wannemacher RW Jr, McCoy JR. Determination of optimal dietary protein requirements of young and old dogs. Journal of Nutrition. 1966;88(1):66-74. doi:10.1093/jn/88.1.66. pubmed.ncbi.nlm.nih.gov/5900634
3. Freeman LM. Cachexia and sarcopenia: emerging syndromes of importance in dogs and cats. Journal of Veterinary Internal Medicine. 2012;26(1):3-17. doi:10.1111/j.1939-1676.2011.00838.x. pubmed.ncbi.nlm.nih.gov/22111652
4. Lawler DF, Larson BT, Ballam JM, et al. Diet restriction and ageing in the dog: major observations over two decades. British Journal of Nutrition. 2008;99(4):793-805. doi.org/10.1017/S0007114507871686
5. Hutchinson D, Sutherland-Smith J, Watson AL, Freeman LM. Assessment of methods of evaluating sarcopenia in old dogs. American Journal of Veterinary Research. 2012;73(11):1794-1800. doi:10.2460/ajvr.73.11.1794. pubmed.ncbi.nlm.nih.gov/23106466
6. O'Neill DG, Elliott J, Church DB, et al. Chronic kidney disease in dogs in UK veterinary practices: prevalence, risk factors, and survival. Journal of Veterinary Internal Medicine. 2013;27(4):814-821. doi:10.1111/jvim.12090. pubmed.ncbi.nlm.nih.gov/23647231
7. Jacob F, Polzin DJ, Osborne CA, et al. Clinical evaluation of dietary modification for treatment of spontaneous chronic renal failure in dogs. Journal of the American Veterinary Medical Association. 2002;220(8):1163-1170. doi:10.2460/javma.2002.220.1163. pubmed.ncbi.nlm.nih.gov/11990962
8. Moe SM, Zidehsarai MP, Chambers MA, et al. Vegetarian compared with meat dietary protein source and phosphorus homeostasis in chronic kidney disease. Clinical Journal of the American Society of Nephrology. 2011;6(2):257-264. doi:10.2215/CJN.05040610. pubmed.ncbi.nlm.nih.gov/21183586
9. Linde A, Lahiff M, Krantz A, Sharp N, Ng TT, Melgarejo T. Domestic dogs maintain clinical, nutritional, and hematological health outcomes when fed a commercial plant-based diet for a year. PLOS ONE. 2024;19(4):e0298942. doi:10.1371/journal.pone.0298942. pubmed.ncbi.nlm.nih.gov/38625934
10. Knight A, Huang E, Rai N, Brown H. Vegan versus meat-based dog food: Guardian-reported indicators of health. PLOS ONE. 2022;17(4):e0265662. doi:10.1371/journal.pone.0265662. pubmed.ncbi.nlm.nih.gov/35417464
11. Petaluma. Nutritional analyses for Roasted Peanut Butter & Sweet Potato Flavor Baked Food for Adult Dogs (2026), Baked Pumpkin & Peanut Butter Flavor Baked Food for Senior Dogs (2026), and Whole Food Mixer (2025). feedpetaluma.com

This article is for educational purposes and does not replace advice from your veterinarian. Talk with your vet before changing your dog's diet, especially if your dog has kidney disease or another health condition.