Experts have cast doubt over a study which claims slimming creams may actually work.
The survey suggests slimming creams could work
A survey carried out by a French consumer magazine showed two slimming creams were able to reduce women's thighs by 2cm in just two weeks.
But consultant dermatologist at North Middlesex Hospital, Dr Nick Mann, said the claims are dubious.
"It's impossible to see how a cream like that could affect body tissue," he said.
The French equivalent of Which? magazine, 60 million de Consommateurs, conducted a slimming cream study on 220 women.
Ten groups comprising 20 women each tested a different cream, while a further 20 were given a placebo moisturiser.
Women were told to rub the cream into one thigh twice a day, and were followed up every two weeks.
They found two creams - L'Oreal's PerfectSlim and Elancyl's Chrono-Actif were able to reduce the circumference of women's thighs by 2cm in just two weeks.
However it is not clear whether the study looked at other influencing factors such as lifestyle or diet.
Previous tests by the magazine have never shown slimming or anti-cellulite creams be more effective than a thigh massage.
Editor of the magazine, Marie-Jeanne Husset said: "This time our test came to the very conclusion that women want to hear.
"People have been astonished to find us giving the thumbs up."
However Dr Mann told BBC News Online: "I would be dubious about the survey's claims."
"It is difficult to imagine how these creams have the effect they claim to have."
"I can't understand how anti-cellulite creams could affect anything other than the surface of the skin."
Dr Mann added that more explanation is needed about how these creams claim to work.
Meanwhile, the survey results have caused a massive surge in sales, with stock selling out in one of Paris's main department stores.
But if the claims are shown to be true through proper clinical trials, it could backfire on the industry.
Ms Husset said because slimming creams are not classed as medicines, their ingredients are not listed.
"The companies will not be pleased with our findings as they strengthen the argument for regulation. The last thing they want is for slimming creams to be listed as medicines."