The Candy Company That Quietly Became America's Biggest Vet

Your dog eats Mars. Your dog's food comes from Mars. And when your dog gets sick, the clinic you drive it to is, more likely than not, owned by Mars too. The same company that puts M&Ms in your kid's lunchbox is the biggest veterinary provider in America⁷ - and somewhere along the way, the candy stopped being the main event. By 2023, the part of Mars that feeds and treats pets was estimated to be larger than the part that makes chocolate.

The official story is that Mars is a candy company that happens to dabble in pet food. The real story is the reverse: Mars is a pet-care company that happens to be famous for candy, and it got there on purpose, one adjacent step at a time, over ninety years - while everyone kept staring at the chocolate.

It started with a tin of dog food in 1935

The march began long before anyone thought to write a headline about it. In 1935, by Mars's own corporate history, the company bought the U.K.'s Chappell Brothers, makers of CHAPPIE canned dog food.³ (A British industrial-history reference dates the share-capital purchase to 1934, with manufacturing moving to Slough afterward - turnover there climbing from £19,000 toward nearly £100,000 as the plant scaled.⁴) Either way, the entry point is the same: a confectioner deciding that the thing it was good at - mass-producing a cheap, shelf-stable, branded consumable people bought again and again - applied just as well to dogs as to children. The product changed. The repeat-purchase machine did not.

That is the quiet logic of an adjacency march. Each step is small enough to look like a sideline and close enough to the last one that the existing muscle still works. Dog food led to premium dog food. Premium dog food led to the place premium dog food is recommended - the vet's office. Mars didn't leap from candy to clinics. It walked there, and the walking took the better part of a century.

From the food bowl to the exam table

The decisive move was upmarket. In 2001, Mars bought a controlling stake in Royal Canin - a premium pet-nutrition brand founded in 1967 by a veterinarian - paying roughly $730 million for a 56.4% stake from the French bank BNP Paribas.⁷ Royal Canin was not just better dog food; it was dog food sold through veterinarians, prescribed like medicine. That gave Mars a foot inside the clinic door. The next step was to own the door itself. Mars had taken its first stake in the Banfield clinic chain years earlier, and over the following decades it accumulated BluePearl and others, until in 2017 it spent approximately $9.1 billion - including $1.4 billion in assumed debt, at $93 per share - to acquire VCA, the largest U.S. veterinary-hospital operator.¹ The deal closed that September, with VCA folded in alongside Banfield, BluePearl, and Pet Partners.²

Now watch the loop close. Mars makes the food a vet recommends, owns the vet who recommends it, and owns the diagnostics that decide which food gets recommended. The clinic recommends Royal Canin; the food sells; the food brings the pet back to the clinic. It is a flywheel built out of acquisitions - and the same instinct that once sold a child a chocolate bar now sells a dog's owner a lifetime of bags, visits, and prescriptions.

When the dog food got bigger than the candy

By 2023 the arithmetic had crossed over. Mars is private and publishes no segment financials, so every number here is an outsider's estimate - but the estimates converge. Petfood Industry pegged Mars Petcare's 2023 revenue at roughly $20 billion against a company total north of $50 billion.⁵ One multi-decade study went further, estimating pet care at 59% of revenue, snacking at 38%, and food and nutrition at the remaining sliver.⁶ However you cut it, the pet business is no longer the sideline. The sideline became the main line while the brand's reputation stayed frozen in the candy aisle.

But didn't Mars just buy $36 billion of snacks?

The honest objection is that the 'pet care is bigger' story has an expiration date - and it may already have passed. In December 2025, Mars closed a $36 billion acquisition of Kellanova, the former Kellogg's snack business behind Pringles, Pop-Tarts, and Cheez-It.⁸ That adds a very large pile of snack and confectionery revenue to the other side of the ledger and complicates any neat claim that pets outweigh candy today. A second, fairer caution: because Mars discloses nothing, the 59% figure is one analyst's estimate, and the more conservative read - food-only, with vet services counted separately - lands closer to a strong plurality than an outright majority.

Both points are true, and neither dents the thesis. The crossover was real as of 2023, and a single 2025 deal doesn't retroactively make Mars a candy company - it makes Mars a company big enough in pets that it could spend $36 billion buying its way back to confectionery scale. That's not a retreat from the pet strategy. It's the move of a company so dominant in its chosen adjacency that it had the balance sheet to go shopping in its old neighborhood. The candy didn't reclaim Mars. Mars reclaimed the candy.

The most valuable thing Mars built wasn't a chocolate bar or a clinic. It was a habit - of treating the business it was famous for as just the first room in a much longer hallway. Ninety years after a confectioner bought a tin of dog food, the dog food was bigger than the chocolate, and almost nobody had noticed, because Mars never bothered to correct them. The brand everyone could see was the candy. The company that actually grew was the one feeding their pets.