EXPRESS: What Goes in the Bowl? Evidence-Based Nutrition for Ageing Domestic Cats.

With the increasing life expectancy of domestic cats, there is a growing imperative to understand and address the unique nutritional needs of senior felines. This review critically examines current knowledge regarding the physiological changes associated with feline ageing, the nutritional requirements of older cats, and the gaps in research and regulatory nutritional standards that persist in this field. Despite the importance of nutrition, there are no official guidelines for senior or geriatric cats. Veterinary recommendations focus on energy, protein, fat (including essential fatty acids), and water, but these are largely extrapolated from adult cat requirements. The literature reveals a focus on canine ageing, with feline-specific studies remaining scarce. Where research exists, it highlights the benefits of enriched diets (e.g., fish oil, vitamins, B vitamins, arginine) and targeted supplementation (e.g., vitamin E, ß-carotene, linoleic acid, chicory root) in improving cognitive function, longevity, and intestinal health. However, robust, contemporary evidence for nutritional interventions in ageing cats is limited. Energy requirements, which underpin diet formulation, are inconsistent between studies and largely rely on non-peer reviewed data (i.e., conference proceedings) or meta-analyses. Protein is central to feline health, yet optimal levels for seniors are not empirically established, and age-related amino acid requirements are largely unexplored. Fat digestibility may decline with age, but the impact on fat-soluble nutrient status (e.g., vitamins A, D, E, K) is not well understood. Micronutrient deficiencies, particularly in B vitamins (B6, thiamine, B12), are more prevalent in older cats, often due to reduced intake and assimilation. Regulatory frameworks lack senior-specific nutritional standards, and commercial diets marketed for older cats often do not differ substantially from adult formulations. This review calls for evidence-led approaches, advocating for reputable brands that conduct dietary trials and publish peer-reviewed data on their senior formulations.