If stress relief is one reason people like to chew gum, Todd Stitzer could have been forgiven for reaching for a pack of Trident yesterday morning.

Not only is the Cadbury chief executive in the middle of swapping his swanky Mayfair office for a business park in Uxbridge, now two unexpected guests are also threatening the company's lucrative grip on the global gum market.

Since Mr Stitzer's well-judged acquisition of the US gum group Adams in 2003, gum has been an important driver of growth at Cadbury.

While sweets and chocolates have struggled, the £10 billion global gum market has been growing at a brisk 8 per cent per year, driven by gum's appeal as an alternative to high-calorie snacks and cigarettes.

By rolling out new products in new countries, Cadbury has been gnawing away at its rival Wrigley's hold on the market. Now the pairing of the Sage of Omaha and the company that invented the Mars bar have gatecrashed the party.

For bankers starved of deals, the $23 billion cash acquisition is a very welcome treat. But as Mars made clear, it found financing the deal difficult.

With many of the banks that would normally have provided the funds rather short of readies themselves these days, Mars had to call on the famously sweet-toothed Mr Buffett to dip into his huge cash pile.

In return, Mr Buffett has bought his stake in Mars' new Wrigley subsidiary at half the price Mars is paying the existing owners.

Wrigley, a sleepy, family-controlled Chicago company, had any way been showing signs of waking up recently but under the ownership of Mars, Cadbury will have a real fight on its hands.

For Mr Stitzer, the timing of the new challenge could not have been worse.

He and Ken Hanna, his finance director, are battling to drive through a big programme of cost cuts, including the loss of thousands of jobs, while finally pulling off the demerger - after the planned sale was aborted by the credit crunch - of the group's US soft-drinks arm.

With the corporate raider Nelson Peltz hovering on the sidelines, there have been rumblings that if the duo fail to lift profit margins this year, their days at the helm may be numbered.

They will now have to roll up their sleeves to fight against an emboldened, cash-rich competitor and also have to consider whether Cadbury needs to bulk up in return.

By gobbling up Wrigley, Mars will overtake Cadbury as the world's biggest sweety company, with 14 per cent of the global market, compared with Cadbury's 10 per cent.

One possibility would be for Cadbury to look again at a tie-up with another sleeping American confectionery giant, Hershey.

It would give Cadbury extra clout in the vast US confectionery market and, coincidentally, divert attention from the more pressing challenges Cadbury faces.

But it would be very far from straightforward, as previous efforts have shown.

Trying to second guess the complex web of politics at Hershey, which is controlled by a charitable trust with strong links to the small Pennsylvania town of the same name, is an extremely tricky game.

Another possibility is of course that Cadbury becomes a target itself, perhaps for a Nestlé or Kraft. The fact that Cadbury's share price rose yesterday suggests that some investors think this may be the most likely outcome.

As he loads up his boxes for the move from Berkeley Square, Mr Stitzer has a lot to chew on.

david.wighton@thetimes.co.uk

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