Supplements are common in dogs, Dog Aging Project data suggest

A new Dog Aging Project analysis suggests supplements are now a mainstream part of canine care in the US, at least among participating households. In the study, published online in late 2025 and appearing in the February 1, 2026, issue of the American Journal of Veterinary Research, researchers analyzed enrollment survey responses from 40,367 dogs and found that 20,993, or 52%, were receiving supplements. Omega-3 fatty acids and joint supplements were the leading categories, each reported in more than half of dogs receiving supplements. (pubmed.ncbi.nlm.nih.gov)

The findings fit with the broader mission of the Dog Aging Project, a large US longitudinal study designed to understand how biology, lifestyle, and environment shape healthy aging in dogs. Participating pet parents complete a detailed Health and Life Experience Survey covering diet, health history, environment, and behavior, creating a large real-world dataset that has already supported studies on feeding frequency, disease patterns, activity, and joint supplement use. In 2022, one of the project’s first supplement-focused papers reported that 40% of 26,951 adult dogs received some type of joint supplement, with use more common in older, larger, and previously overweight dogs. (data.dogagingproject.org)

The new AJVR paper broadens that lens from joint products to supplements overall. Its objective was to identify what supplements dogs in the cohort were receiving and how often dogs with selected health conditions were being given products thought to support those conditions. The analysis used owner survey responses collected between January 1, 2020, and December 31, 2022, and included free-text review of “other” supplement responses to capture additional categories. The headline result was simple: about half of enrolled dogs were getting supplements, and dog-level demographic factors appeared to explain differences in use more strongly than pet parent demographics. Orthopedic conditions stood out as a major driver of supplement administration, consistent with the earlier Frontiers paper linking osteoarthritis diagnosis and joint supplement use. (pubmed.ncbi.nlm.nih.gov)

That pattern will likely feel familiar in practice. The earlier Dog Aging Project study found dogs with a clinical diagnosis of osteoarthritis were much more likely to receive a joint supplement than dogs without such a diagnosis, with an odds ratio of 3.82. It also found that supplement use rose with age and body size, while mixed-breed dogs were somewhat less likely to receive joint supplements. Together, the two studies suggest supplement use is not fringe behavior among engaged pet parents, but part of how many households respond to mobility concerns and age-related change. (frontiersin.org)

The researchers’ clinical relevance statement was direct: veterinary professionals should consider spending more time discussing supplement use with dog owners, especially for senior pets. That recommendation matters because these data reflect what pet parents are already doing at home, regardless of whether a product has strong evidence behind it. The 2022 Frontiers paper explicitly noted that efficacy for many joint supplements remains controversial, and the Dog Aging Project’s survey-based design means the new study cannot establish whether supplements improved outcomes. What it does show is the scale of use, which has implications for history-taking, nutrition counseling, adverse event recognition, and conversations about cost and expectations. (pubmed.ncbi.nlm.nih.gov)

For veterinary teams, the practical message is that supplement questions probably deserve the same routine attention as diet, treats, and preventives. If half of dogs in this large US cohort are receiving supplements, clinicians may be missing clinically relevant information when they don’t ask specifically what products are being used, why pet parents chose them, and whether those products were recommended by a veterinarian, a breeder, social media, or retail marketing. This is especially relevant in senior care, mobility cases, multimorbidity, and nutrition consults, where supplements can overlap with therapeutic diets, prescription drugs, and pet parent expectations for “natural” support. The earlier literature also suggests supplement use in dogs may exceed comparable rates in people for joint products, underscoring how normalized these products have become in companion animal care. (pubmed.ncbi.nlm.nih.gov)

What to watch: The next important step is longitudinal analysis. Because the Dog Aging Project follows dogs over time and continues to release curated datasets, future studies may be able to test whether specific supplement patterns are associated with meaningful clinical outcomes, or whether they mainly reflect disease burden, pet parent preferences, and access to care. For now, the clearest signal is behavioral: supplement use is common, it varies by life stage and condition, and it’s something veterinary professionals should expect to address more often in the exam room. (pubmed.ncbi.nlm.nih.gov)