MURFREESBORO, TENN. — Despite being a small category, fresh pet food has seen massive growth and has stood out as a key contributor in the pet food sector, seeing more growth (18.2%) than any other format from 2024 to 2025, according to data from NielsenIQ. However, as the category expands, certain marketing claims made by fresh pet food companies may be damaging consumer trust in traditional pet food formats such as kibble.
In a recent review published in the journal Animals, researchers from the School of Agriculture of Middle Tennessee State University analyzed three of the most common claims used by fresh pet food companies: that additives and preservatives are harmful; that human-grade ingredients offer superior safety and nutrition; and that whole ingredients provide greater health benefits than processed alternatives. The research assessed the scientific evidence supporting each claim and evaluated their potential health impact on dogs and cats.
To analyze the evidence of the claims, the researchers conducted a comprehensive literature search across the SCOPUS, PubMed and EBSCO databases, and identified 4,888 potential studies. Following systematic screening and quality assessment, 121 studies met inclusion criteria for analysis.
“Pet owners today face an overwhelming array of dietary options for their companions, from grain-free kibble to fresh-frozen meals and boutique brands, each marketed with claims of superior nutrition and improved health outcomes,” the researchers wrote. “Understanding these options and their consequences on pet health is essential for both consumers making purchasing decisions and veterinary professionals recommending dietary formats.”
Additives and preservatives
For additives and preservatives, effect direction was determined by analyzing adverse event rates, toxicity indicators and clinically relevant health outcomes.
The analysis found that there isn’t enough evidence to support any claims that additives and preservatives that are deemed safe by the Association of American Feed Control Officials (AAFCO) have any adverse effects. The adverse event rates between treatment and control groups were nearly identical, attributing the differences to normal biological variations rather than toxicity from ingredients, according to the review.
“Current evidence does not substantiate claims that approved additives and preservatives cause harm when used within AAFCO guidelines,” the researchers wrote.
Human-grade superiority
For human-grade versus feed-grade ingredient comparisons, a dual classification approach was integrated to address both the safety and nutritional aspects. Safety assessments utilized regulatory thresholds established by the US Food & Drug Administration (FDA) and US Department of Agriculture (USDA) for human food safety. The comparison yielded only six eligible studies, all of which exhibited methodological limitations that prevented definitive conclusions.
According to the researchers, the nutritional comparison studies showed high risk of bias due to industry funding, absence of blinding protocols and non-identical formulation parameters between compared diets. The confounding of ingredient grade with differences in nutrient profiles, ingredient compositions and processing methods made it impossible to isolate the specific effects of ingredient grade on pet health outcomes.
While safety assessments did suggest that feed-grade ingredients may contain higher contaminant levels, the limited sample size and lack of standardized definitions for human-grade and feed-grade ingredients across studies led to inconsistency and inability to generalize these findings, according to the researchers.
“Human-grade versus feed-grade ingredient comparisons showed methodological limitations and high risk of bias, preventing definitive conclusions,” the researchers wrote.
Whole vs. processed
For processing effects on ingredients, effect direction was established through analysis of digestibility coefficients, nutrient retention profiles, antinutrient reduction and bioavailability metrics.
The review found that ingredient type emerged as the most significant moderator of processing outcomes, with variations causing large fluctuations in outcomes. Likewise, processing methods were significant moderators of both digestion and nutrient content. Processing intensity showed no significant moderation of outcomes.
“Random-effects meta-analyses of processing effects on ingredient digestibility and nutrient content demonstrated significant heterogeneity, with outcomes highly dependent on ingredient type and processing method rather than processing intensity,” the researchers wrote. “… These findings indicate that processing effects are highly context-dependent and cannot be generalized across all ingredients or pet food formulations.”
Overall, while any of these claims may be true, currently there isn’t enough scientific evidence to prove they are true, according to this analysis. In order to change this moving forward, fresh pet food brands can focus on making evidence-backed claims, clarifying lack of evidence on marketing claims and even participating in further research to support the claims.
“This review identifies critical research gaps and provides recommendations for evidence-based marketing practices, targeted research priorities and informed decision-making by industry professionals and consumers,” the researchers explained. “Pet food companies should ensure that all marketing claims are backed with accessible and peer-reviewed scientific evidence before conveying them to consumers, allowing for informed decisions to be made.
“Minimally processed diets should be assessed against identical ingredient matrices or similar formulations to draw more conclusive evidence,” they added. “Likewise, these studies necessitate larger sample sizes to sufficiently power the analytical tests to statistical significance. Comprehensive prospective studies are needed to establish whether processing intensity causally affects long-term health outcomes in companion animals across their lifespan, employing standardized outcome measures and controlling for ingredient composition, nutritional intake and variability between pets.”
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