The soaring popularity of the Atkins Diet has seen 2 million Britons declare war on their waistlines. But it is not just flab that is feeling the pinch.

The slimming industry, food manufacturers and beer brewers are all seeing their profits slimmed down as devotees empty their fridges of any product with the cheek to carry a carbohydrate.

Dr Robert C Atkins pioneered his low-carbohydrate, high-protein regime more than 30 years ago. His controversial theory allows followers to eat bacon and sausage for breakfast, but bans bread, pasta and beer.

Helped by a string of celebrity endorsements by Hollywood actresses such as Jennifer Aniston and Minnie Driver, the diet is now an economic entity equivalent to the GDP of a small African country.

But its popularity has come at a cost. Earlier this week, the food company Unilever reported heavy losses, saying the success of the Atkins Diet had eaten into sales of its own Slim-Fast products.

Wrapped and sliced bread sales have been another victim of the Atkins phenomenon. John White, director of the Federation of Bakers, said: "Sales have been declining by 2 per cent every year over the last few years, and Atkins is definitely a factor. Everyone seems to be on it, and people seem almost evangelical in their support of it. We can only hope that it's a fad that will pass."

Bakers are planning a promotional offensive to counter the "Atkins effect". October will see the launch of the first British Bread Month, with the slogan "Use your loaf, have another slice" and initiatives promoting the health benefits of bread. The Flour Advisory Bureau has signed up the actress Denise Van Outen to front its Supermodel Eating System, a campaign which promotes bread as part of a balanced diet. The bureau is also funding a study by the Medical Research Council into the benefits of a high-carbohydrate diet, the polar opposite of Atkins. Results will be published in September.

Another Atkins victim is the humble potato, which has also seen sales slump. The British Potato Council is giving its product a £1m makeover, directly taking on its Atkins nemesis with a slogan proclaiming "fab not fad".

Others have gone for the "if you can't beat 'em, join 'em" approach. Anheuser-Busch, the company which brews Budweiser beer in the UK, is launching Britain's first "low-carbohydrate, low-calorie" lager next week. The beer is aimed at clawing back those Atkins adherents who have given up their post-work pints, as well as luring female drinkers. The svelte TV soccer presenter Gabby Logan has been lined up for the launch at the Hempel hotel in London, and the beer's "brewmaster" is a woman.

There have been winners from the Atkins revolution. Supermarkets have reported record fruit sales. Tesco says demand for watermelons is up 64 per cent on the same time last year, while peppers are up 42 per cent, raspberries 38 per cent and apples 37 per cent.

The Meat and Livestock Commission has also reported increased sales in the past three years. A spokesman said: "There's a definite rise in meat sales across the board. The Atkins Diet is a definite factor in the rise."

Next year, Atkins Nutritionals Incorporated, which runs the global business, will launch its own range of low-carb chocolate bars and ice-creams in Britain, adding to its already fattened profits.

Since the first Atkins New Diet Revolution was published in the UK four years ago, it has sold two million copies. The latest offering, Atkins for Life, was launched in March and already 144,000 copies have flown out of bookshops.

The death of the man himself three months ago only seems to have increased demand for his weight-loss secrets. A spokeswoman for Vermillion, part of the Random House group which publishes the New Diet Revolution, said that the book has been selling 150,000 copies a month since Atkins suffered a fatal brain haemorrhage in April.

Atkins published his first diet book in America in 1972, but it is only in the past few years that it has become a global brand. Britain is the second biggest market, followed by Japan and, surprisingly given the ban on pizza and pasta, Italy.

The privately owned Atkins company is reticent about its profits, but admits that sales now run into hundreds of millions of dollars. At any one time, one in three Americans say they have been, are, or are planning to go on the diet.

Other diet brands are hoping the Atkins effect will be as transitory as the careers of some of the celebrities who endorse it. A spokeswoman for WeightWatchers said: "Our subscriptions have continued to increase year on year, and we have over a million members. Atkins appeals to people who want to lose weight quickly, maybe for a wedding or a school reunion, whereas our regime is sustainable but requires a long-term lifestyle change."

As he announced his company's losses this week, Niall Fitzgerald, chairman of Unilever, grumbled: "If you think you can live the rest of your life on beef and high-fat products, you're mistaken."

Unfortunately for him, the latest Atkins edition is devoted entirely to how you can spend the rest of your life on the diet.