180m: That's what Britain is spending on 'free from' foods and market will double in five years

But do they really boost health? Or is the nation's obsession another sign of our growing introspection? Susie Mesure investigates

The British food industry is cashing in on one of the fastest growing trends to sweep supermarket aisles, as shoppers send sales of "free-from" foods skyrocketing to over 180m this year.

With a burgeoning number of celebrities citing food intolerances as a reason for restrictive diets, these statistics suggest that ordinary people are following suit and cutting out whole food groups in favour of expensive wheat-free, gluten-free and dairy-free alternatives.

Dieticians have warned that the vast majority of the 27 million Britons claiming to be intolerant to one food group or another have been duped by "snake oil" food testers, but shoppers just can't seem to get enough of them.

And with everything from cakes to chocolate macaroons and muesli available in "free-from" form, the fashion looks set to continue. Market research firm Mintel predicts that the free-from market will double to more than 350m by 2012.

Monica Grenfell, a nutritionist and the author of several best-selling diet books, said: "Everyone is spending a fortune on special ranges."

She added: "There is a lot of messing and fussing about with people suggesting they have food intolerances when they have no such thing."

The idea that food intolerance may be just another diet fad is not helped by the number of svelte celebrities revealing that they are sufferers. At the last count they included Rod Stewart's former wife, Rachel Hunter, who can't stomach lactose, the actress Rachel Weisz, who avoids wheat, and the actor Billy Bob Thornton, who eschews wheat, dairy and shellfish. More and more food allergies and intolerances are being written into television scripts: Ross from Friends couldn't eat kiwi fruit, while one Ugly Betty plot line featured a nut allergy.

Such fanciful storylines and the association of food intolerances with pampered Hollywood stars serves to reinforce the belief of many medical experts that food exclusion may be just another symptom of an increasingly affluent and self-obsessed nation.

"We are a wealthy country, and we've moved towards a policy of individualism. We expect to have our own 'tailored' diets, to fit our 'tailored' lifestyles we have an infinite number of choices. The rise in food intolerances could be due to a combination of neuroticism, hypochondria, and individualism," said author and psychologist Phillip Hodson, a fellow of the British Association for Counselling and Psychotherapy.

In the UK, lactose-free products have taken the largest chunk of the free-from market, at 48 per cent, overtaking gluten-free breads, biscuits and cakes as more people substitute soya milk for cow's milk. Alpro, which accounts for four out of every five cartons of soya milk sold here, is the biggest player. Niche markets, including nut- or egg-free, are growing the fastest, with sales up 43 per cent in the past year alone.

Tesco has jumped on the bandwagon, increasing the number of items in its free-from range to 150. Sales of the range have jumped by 27 per cent in the past 12 months.

Sainsbury's offers less than half the choice of the Tesco range, but sales are growing at 37 per cent a year. This, a spokesman said, was mainly due to more people opting to eat their bread and cakes free from wheat, gluten or dairy products.

Ironically, the expanding ranges of free-from food could spell trouble for the growing number of Britons with coeliac disease, which means they have a gluten intolerance. Sufferers warn that the boom in free-from foods is leading the NHS to revise whether gluten-free foods should continue to be available on prescription.

"Free-from basic staple items are much more expensive than normal foods, and removing bread, pasta etc from prescriptions will affect many coeliac sufferers," said Catherine Reid, who was diagnosed with coeliac disease last February.

Although coeliac disease affects one in every 100 British people, nutritionists believe that millions of others have been misdiagnosed as suffering from a food intolerance. Ms Grenfell said: "It's the 'snake oil' guys that annoy me people making huge amounts testing people who can't really afford to pay 400 to be told they've got a yeast intolerance, when the truth is that they were just drinking too much beer. The whole thing is just a racket."

But Muriel Simmons, chief executive of Allergy UK, hit back at insinuations that the public were dreaming up their own food illnesses or merely copying celebrities in opting to cut certain food groups out of their diets.

"That suggestion is insulting to the general public," she said. "I get very cross when people say 'Isn't this just a condition in the mind?'

"People don't dream up problems such as migraines and Irritable Bowel Syndrome. These conditions are not fun to have."

Fad or fact? Please don't give us our daily bread...

They may have the choice of life's luxuries, but it seems that more and more celebrities prefer to deny themselves foods containing gluten, wheat, dairy and other products:

Shellfish

Billy Bob Thornton

He had no problem getting married with a vial of Angelina Jolie's blood around his neck, yet the hard-man actor shies away from foods containing wheat, dairy, and shellfish.

Gluten

Carol Vorderman

Detoxing helped the 'Countdown' queen cope with her gluten intolerance, which is also known as coeliac disease. The condition affects the digestive tract and can cause diarrhoea, weight loss and fatigue.

Wheat

Rachel Weisz

The British actress has openly discussed her wheat intolerance, which takes bread, pasta, couscous, noodles, cakes, and drinks such as beer and vodka off the menu.

Milk

Denise Lewis

A strong intolerance to cow's milk and a lesser yeast intolerance hasn't slowed Olympic medallist Denise.

Lactose

Rachel Hunter

The supermodel said that taking a food allergy test was the best thing she ever did. She now shuns lactose, which means avoiding milk and other dairy products.