Iams and Eukanuba honest review: the Mars brands between B and C
Iams and Eukanuba share a common history, a common owner, and a common position in our scoring grid: tier C, between 58 and 60 out of 100. These are the kibbles you find in supermarkets and pet store chains, often marketed as a "serious" step up from Pedigree or mass-market brands. The nutritional reality is more nuanced.
This article analyses both brands in depth: their history, their ingredient-by-ingredient composition, their scores across our five dimensions, and what you should buy instead if you want to do better without breaking your budget.
French version: Iams et Eukanuba avis honnete.
Context: Mars Petcare and its brand pyramid
To understand Iams and Eukanuba, you need to understand their owner. Mars Petcare is the world's largest pet food company, with estimated annual revenues of $18 billion. Its portfolio covers every price segment, from mass grocery to premium veterinary.
The Mars pyramid looks like this:
| Brand | Segment | PetFoodRate Score |
|---|---|---|
| Pedigree | Mass grocery | D (42/100) |
| Iams | Mid-range | C (58/100) |
| Eukanuba | Mid-high range | C (60/100) |
| Royal Canin | Vet premium | C (57/100) |
| Cesar | Premium wet food | C (55/100) |
In 2014, Mars acquired Iams and Eukanuba from Procter & Gamble for $2.9 billion. P&G had bought Iams in 1999 and subsequently launched Eukanuba as a distinct premium line. Under Mars, both brands were progressively repositioned to coexist without cannibalising each other, with Eukanuba maintained as the slightly more premium product.
This acquisition partly explains why the formulas have not evolved significantly in over a decade. Innovation in these ranges is not a priority when the objective is to maximise returns on established assets.
Iams ProActive Health Adult: full analysis (58/100)
Declared composition
The flagship Iams adult dog product lists the following ingredients: chicken (29%), chicken meal, corn, beet pulp, barley, chicken fat (preserved with mixed tocopherols), minerals, flaxseeds, chicory (0.5%), methionine, vitamins and trace elements.
Detailed sub-scores
| Dimension | Score | Grade | Comment |
|---|---|---|---|
| Proteins | 14/35 | C | Chicken first but corn and barley follow immediately |
| Nutrition | 13/20 | B | Acceptable profile, adequate omegas |
| Undesirables | 12/20 | C | Corn and barley present, no artificial colours |
| Transparency | 10/15 | B | Chicken percentage declared (29%) |
| Adaptability | 9/10 | A | Standard adult dog formula |
| Total | 58/100 | C |
What pulls the score down
Corn is the third ingredient on the list. After fresh chicken (which contains 70 to 75 percent water, meaning it weighs a lot in volume but much less once dehydrated) and chicken meal, we hit corn immediately. It is a filler carbohydrate that increases ration volume without providing significant protein value for a facultative carnivore.
Our analysis of animal vs plant proteins in pet food explains why this distinction matters: dogs can metabolise plant proteins but their digestibility is lower than that of animal proteins. Every calorie of corn is a calorie that could have been meat.
Beet pulp is not a negative: it is a fermentable fibre that supports intestinal health. But its presence confirms that the formula is compensating for insufficient natural animal fibre with an added functional ingredient.
What deserves credit
Iams is one of the rare C-tier brands to declare the percentage of fresh meat on the label. 29 percent fresh chicken is a transparency commitment that Royal Canin does not make on its general formulas.
Chicken fat preserved with tocopherols (natural vitamin E) rather than BHA or BHT is a genuine positive. On the undesirables dimension, Iams avoids the most problematic synthetic preservatives.
Flaxseeds contribute omega-3 ALA. This is not as bioavailable for dogs as marine-source EPA/DHA omega-3s, but it is better than nothing. Our article on omega-3 in pet food details the differences.
The comparison that changes everything
Brit Care Adult Large Breed scores A (84/100) and is available through the same retail channels as Iams, at a similar or marginally higher price. For 0.15 to 0.20 EUR more per day for a 15 kg dog, you move from a C (58) to an A (84). That is not a marketing argument - it is nutritional arithmetic.
Eukanuba Medium Adult: full analysis (60/100)
Declared composition
Eukanuba Medium Adult: chicken (31%), chicken meal, corn, barley, chicken fat (preserved with mixed tocopherols), dried beet pulp, fructo-oligosaccharides (FOS), minerals, flaxseeds, mannan-oligosaccharides (MOS), vitamins and trace elements.
Detailed sub-scores
| Dimension | Score | Grade | Comment |
|---|---|---|---|
| Proteins | 15/35 | C | Chicken slightly higher than Iams |
| Nutrition | 13/20 | B | FOS and MOS: genuinely useful prebiotics |
| Undesirables | 13/20 | C | Same profile as Iams, corn and barley present |
| Transparency | 10/15 | B | Chicken 31% declared |
| Adaptability | 9/10 | A | Well-calibrated medium-breed formula |
| Total | 60/100 | C |
The two-point gap over Iams
Eukanuba scores 60 vs 58 for Iams. Two points justified by two concrete formula differences.
First difference: chicken content is declared at 31 percent versus 29 percent for Iams. The gap is not spectacular, but it is consistent with Eukanuba's slightly premium positioning. In our scoring system, every percentage point of animal protein in the leading ingredients counts.
Second difference: FOS (fructo-oligosaccharides) and MOS (mannan-oligosaccharides). These prebiotics are not present in the standard Iams formula. FOS feeds bifidobacteria in the gut microbiome. MOS blocks the adhesion of pathogens like Salmonella and E. coli to the intestinal wall. Studies published in the Journal of Animal Science show positive effects on stool consistency and overall digestive health.
These two additions place Eukanuba slightly ahead of Iams on the nutrition dimension, accounting for the two-point difference.
What remains insufficient
Corn is still the third ingredient. Barley too. The fundamental formula structure is identical to Iams: one dominant animal protein followed by two grains. Eukanuba scores two points higher than Iams but both remain in tier C.
Eukanuba is sold as a "premium" product in many pet store chains. Its marketing positioning leans on brand heritage and its historical association with the Cincinnati dog show (the Eukanuba National Championship). But that marketing positioning does not show up in the ingredient panel.
Our guide on how to read a pet food label explains why the first ingredient does not tell the full story and why the order of grains matters as much as the order of meats.
The Mars strategy: maximising every segment without self-competition
Understanding why Iams and Eukanuba are Cs rather than As requires understanding Mars Petcare's business logic.
Mars sells Pedigree at 2.50 EUR/kg, Iams at 5-6 EUR/kg, Eukanuba at 6-8 EUR/kg, and Royal Canin at 8-12 EUR/kg. Each brand is positioned to capture a consumer segment, with progressively more sophisticated promises. But moving from a D to an A in our rating would require massive reformulation, which would reduce margins and cannibalise the premium brands in the same portfolio.
This is a dynamic that Consumer Reports has documented in several pet food market analyses: large conglomerates deliberately maintain their mid-range lines at a quality level sufficient to retain customers, but not high enough to challenge their own premium products.
Our article on how kibble is manufactured shows that reformulating towards 70 percent meat content would add approximately 1.20 to 1.80 EUR/kg in raw material costs. For a brand selling millions of tonnes per year, the margin impact is substantial.
Competitive comparison: what you can buy instead
Same budget, better quality
| Product | Score | Price per kg | Daily cost 15 kg |
|---|---|---|---|
| Iams ProActive | C (58) | 5.50 EUR | 0.85 EUR |
| Eukanuba Medium | C (60) | 6.50 EUR | 0.95 EUR |
| Brit Care Adult | A (84) | 6.80 EUR | 0.92 EUR |
| Taste of the Wild | B (78) | 6.20 EUR | 0.90 EUR |
| Edgard & Cooper | A (86) | 8.50 EUR | 1.08 EUR |
The table reveals something important: Brit Care costs less per day than Eukanuba for a 15 kg dog while scoring 84/100 against 60/100. Its higher nutritional density reduces the daily ration required.
For an independent brand reaching A-grade at an accessible price point, our Edgard & Cooper review shows how a brand outside the major conglomerates can reach tier A without the portfolio constraints of a group like Mars.
When Iams or Eukanuba are still acceptable
There are situations where Iams or Eukanuba remain reasonable choices:
-
Gradual dietary transition: if your dog is currently on Pedigree or Royal Canin and you want to improve progressively, switching to Iams or Eukanuba is already a genuine step up (+16 to +18 score points vs Pedigree).
-
Digestive sensitivities: some dogs have stomachs that struggle with very protein-dense formulas. A C (58) with corn may be better tolerated by a sensitive dog in transition than an A (84) introduced too quickly.
-
Very tight budget: if Iams is on promotion at 4 EUR/kg and the nearest A alternative is at 7 EUR/kg, a C still outperforms a D at 3 EUR/kg.
These situations do not justify Iams or Eukanuba as a permanent choice for a healthy adult dog. They simply show that "C" does not mean "harmful" - it means "can do much better".
Eukanuba Breed Specific lines: are they worth it?
Eukanuba has something Iams does not: breed-specific formulas. Eukanuba German Shepherd, Golden Retriever, Yorkshire Terrier and around twenty other references.
Are these scientifically justified? Partially. Kibble size adapted to a specific breed's jaw is a genuine benefit. Texture designed to support mastication in brachycephalic breeds has real value. Caloric density differences according to body size are nutritionally justified.
However, the breed-specific formulas from both Royal Canin and Eukanuba have been criticised by veterinary nutritionists for their marketing sophistication exceeding their scientific basis. An article published in the British Journal of Nutrition showed that nutritional requirements vary more according to age, activity level, and neutering status than by pure breed.
Transparency: where Eukanuba outperforms Royal Canin
This is a point rarely discussed: on ingredient transparency, Eukanuba (and Iams) actually do better than Royal Canin, even though all three score in the same C tier.
Royal Canin frequently uses vague labels such as "dehydrated poultry", "hydrolysed animal proteins", and "poultry by-products" without specifying the exact species or percentages. Eukanuba declares "chicken (31%)" and explicitly names the fat source.
This is not trivial. A dog owner managing a chicken hypersensitivity can read a Eukanuba label and know exactly what they are buying. On some Royal Canin labels, "hydrolysed animal proteins" may contain chicken, pork, or beef without specification.
Year-round cost: the calculation that matters
| Product | Score | Price/kg | Daily ration | Daily cost | Annual cost |
|---|---|---|---|---|---|
| Pedigree | D (42) | 3.20 EUR | 420 g | 1.34 EUR | 489 EUR |
| Iams ProActive | C (58) | 5.50 EUR | 340 g | 1.87 EUR | 682 EUR |
| Eukanuba Medium | C (60) | 6.50 EUR | 320 g | 2.08 EUR | 759 EUR |
| Brit Care | A (84) | 6.80 EUR | 260 g | 1.77 EUR | 646 EUR |
| Acana | A (90) | 7.50 EUR | 240 g | 1.80 EUR | 657 EUR |
Brit Care A (84) costs less per year than Iams C (58) for a 20 kg dog. This is not an exception - it is the rule once you account for nutritional density in the calculation.
Our dog food cost guide breaks down this calculation across the main dog sizes and the main brands on the market.
What Iams offers for cats
Iams also produces cat food. The Iams ProActive Health cat range scores similarly to the dog range - around C (56-62 depending on the product). The logic is the same: an animal protein heading the list followed by grains.
For cat alternatives, our best cat kibble 2026 ranking lists current tier A and B references available across Europe and the US. Since cats are obligate carnivores (unlike dogs, who are facultative), corn and barley in a feline formula are even less defensible than in a canine one.
The wet food and complementary ranges
Both Iams and Eukanuba produce wet food ranges alongside their kibble lines. The wet formats score differently because the water content changes the nutritional calculus significantly.
Iams Perfect Portions wet food
Iams Perfect Portions uses a sealed two-compartment tray format aimed at freshness. The composition follows the same logic as the dry: chicken or salmon as the primary protein, but with a higher meat content percentage on a dry matter basis than the equivalent kibble. This is common across wet foods - the absence of grains needed for extrusion means a higher animal content per calorie.
On our grid, Iams wet formats score B (68-72/100) - a genuine improvement over the dry range C. If you are feeding Iams and want to improve your dog's diet incrementally, introducing wet food alongside dry is one of the simplest upgrades. A 50/50 dry/wet combination brings the average nutritional quality meaningfully above the dry-only tier C.
Eukanuba wet food
Eukanuba's wet range is less prominently marketed than the dry. It uses similar protein sources to the kibble line but, again, the format naturally pushes the meat content higher. Eukanuba wet scores B+ (74-78/100).
Both brands' wet ranges suffer from the same structural issue as their dry lines when compared to premium alternatives: there are better wet options available at similar price points. Our best wet dog food 2026 ranking covers the full comparison, where brands like Lily's Kitchen and Canagan wet consistently outperform Iams and Eukanuba wet.
How to switch your dog from Iams or Eukanuba to a tier A formula
If you decide to upgrade after reading this review, the transition needs to be gradual. Switching too quickly from a C to an A can cause digestive upset - not because the A formula is harmful, but because the gut microbiome needs time to adapt to a higher protein and lower carbohydrate diet.
The standard 10-day transition protocol
| Day | Old formula | New formula |
|---|---|---|
| 1-3 | 75 percent | 25 percent |
| 4-6 | 50 percent | 50 percent |
| 7-9 | 25 percent | 75 percent |
| Day 10+ | 0 percent | 100 percent |
For dogs with known digestive sensitivities, extend this to 14-21 days, spending more time at each stage. Signs that you are moving too fast: loose stools, increased flatulence, reduced appetite, vomiting. If any of these appear, stay at the current ratio for an extra 3-4 days before advancing.
For dogs that have been on Iams or Eukanuba for years without digestive issues, the transition is usually smooth. The shift from corn-based to legume-based or grain-free formulas requires the most gradual approach. If you are switching to Orijen or Acana from Iams, plan for the full 10 days minimum.
Monitoring during transition
Track your dog's stool quality daily (the Bristol Stool Scale adapted for dogs gives you a simple 1-7 metric). Aim for consistent 3-4 scores throughout the transition. Note energy levels and coat appearance - improvements often become visible within 4-6 weeks of completing the switch to a higher quality formula.
Verdict: two decent Cs, but no longer competitive in 2026
Iams ProActive C (58) and Eukanuba Adult C (60) are products formulated in the mid-2000s and minimally reformulated since. They meet legal standards, avoid the worst ingredients (no artificial colours, no BHA/BHT), and offer reasonable label transparency.
But in 2026, the C tier is crowded with alternatives that cost no more and score 25 to 30 points higher. Corn as the third ingredient in a 6-7 EUR/kg formula is no longer competitive when Brit Care (84/100), Taste of the Wild (78/100), and Acana (90/100) are all available through the same retail channels.
If your dog has eaten Iams or Eukanuba for years and is thriving, the switch to an A will not produce a spectacular overnight transformation. But over the long term - bone density, coat quality, energy levels, dental health - feeding a formula with 85 percent meat versus 30 percent produces measurable differences.
Our complete best dog food 2026 ranking lists all tier A options currently available, with updated prices and available formats.
Sources
- FEDIAF - Nutritional Guidelines for Complete and Complementary Pet Food for Cats and Dogs 2024
- Champion Petfoods - About Us
- Journal of Animal Science - Effect of dietary FOS and MOS on intestinal health in dogs
- British Journal of Nutrition - Breed-specific nutritional requirements in domestic dogs: evidence review
- Consumer Reports - Pet Food Quality and Pricing Analysis
- Mars Petcare - Portfolio Overview
- Theo Blanchard, Animal Nutrition Analyst, PetFoodRate