Researchers across the globe are working to get a better understanding of the nutritional needs of older patients
In recent years, domestic cats and dogs are living significantly longer lives, with roughly 20-40% of current pets being considered “old” (more than 11 years of age).1 This is largely due to better quality veterinary care and diet formulation. Despite this trend, information on how cats and dogs age as well as guidelines on their nutritional requirements is limited. This leads researchers to interpret most information about aging from omnivores like humans, who are physiologically different from cats and dogs.
A group of researchers from multiple universities and institutions in New Zealand and Canada aimed to improve our understanding of this area. They reviewed and summarized recent publications regarding canine and feline aging and nutrition. This study found that cats and dogs have several differences in their nutritional requirements, nutrient digestion and intestinal morphology, and microbial diversity. The researchers also discovered specific health benefits of nutritional interventions.
Nutritional requirements differ in both the specific nutrients including amino acids, fatty acids, vitamins, and minerals, and the amounts required. An example of this is the amino acid taurine, which is an essential amino acid for cats, but not for dogs. Additionally, cats are considered obligate carnivores, while dogs are facultative carnivores (animal tissue provides optimal nutrition but is not required). Beyond this information, there is little known about the specific nutritional requirements of cats and dogs.
Fat and protein digestion appears to decrease with aging in cats, indicating that they may be undergoing significant changes in intestinal physiology which can be met with nutritional interventions. On the other hand, dogs undergo changes in intestinal morphology, but experience no changes in intestinal permeability or absorption with aging.
Microbial diversity appears to decrease in aging dogs, affecting their metabolism, nutrient absorption, and response to diseases. In contrast, cats maintain microbial diversity with aging.
Nutritional interventions have shown to improve key processes in aging of cats and dogs including immune status, cognitive function, and maintenance of lean muscle mass. In normal aging, these processes lead to increased frailty and increased risk of diseases and mortality. These nutritional interventions included increasing protein and fat content, and adding nutrients including beta carotene, vitamin E, fatty acids, antioxidants, B vitamins, dietary lipids, carnitine, and amino acids.
The results of this study indicate that aging cats and dogs have different, specific nutritional requirements and a close relationship between diet and their aging processes. With the increasing number of older cats and dogs, this stresses the importance of further research and development of specific nutritional guidelines for aging cats and dogs.
Amanda Bean, BS, is a 2025 PharmD Candidate at the University of Connecticut School of Pharmacy
References
Bermingham EN, Patterson KA, Shoveller AK, Fraser K, Butowski CF, Thomas DG. Nutritional needs and health outcomes of ageing cats and dogs: is it time for updated nutrient guidelines?. Anim Front. 2024;14(3):5-16. doi:10.1093/af/vfae008