Store ready for frenzy over fat-busting pants

John Lewis put another 40,000 pairs of its "fat-busting" knickers — its fastest-selling lingerie range of the past decade — on sale today.

Priced at £25 then, the knickers were soon selling on eBay for up to £60. The price today is £30.

The pants promise to give wearers a better bottom and banish the "orange peel effect". Women insist that, unlike other supposed cures, these pants work — and more than 4,000 signed up for an email alert that they are back, suggesting today's batch will sell out quickly.

The fabric of the knickers contains bio-crystals that warm up on contact with skin. This is said to melt away fat cells which are then excreted by the liver.

Research showed that four out of five women who wore the knickers every day for a month lost inches from their stomach, hips and thighs. Cellulite was also reduced.

The effects are said to last up to 12 months, provided the wearer exercises and eats healthily. Kristen Makin, 32, a marketing executive, said: "I was told about these pants by a friend of mine who said they made her look a dress size smaller and helped create a waistline." Helen Spencer, John Lewis's lingerie buyer, said: "This product is a phenomenon, with customers buying as many as 10 pairs each. Between 80 and 90 per cent of women have cellulite somewhere so there is a huge market for products in this category."