Data from UK drinks consultancy Zenith International shows that bottled water grew by 18 per cent during 2003, compared to a 7 per cent growth in the UK's overall soft drinks market.
Zenith research director Gary Roethenbaugh points out that 63 per cent of current soft drinks consumption are already no or low calorie.
But he expects increasing innovation to capitalize on the path pioneered by Nestle's Contrex brand, targeting young female consumers with its tagline, 'your slimming partner'.
While the claims have proved controversial - Nestle claims that the mineral water contains natural sources of magnesium and calcium, which can increase the body's metabolism and improve weight loss - more waters targeting this function are expected to enter the market.
"Water itself is a zero-calorie product that benefits from the everyday hydration concept," Roethenbaugh told NutraIngredients.com. "But it can be extended to the wellness concept with the addition of minerals and vitamins. We are expecting this trend to grow increasingly."
Among the products launched in the UK this year is the Calorie Controller drink under Prospect Beverages' Vitaminsmart brand. It contains "ingredients that naturally control the appetite and ease hunger feelings", according to the UK company, including echinacea, gingko and ginseng.
Danone is also present in this category with its Taillefine brand, while a number of American products like Skinny Water and H2O light are gaining established sales.
"The Super Size Me launch really brought obesity to centre stage this year. The fact that a documentary film focused on the issue of obesity is an indication of the times we live in. Obesity has become a major cause of concern in Europe, along with smoking," noted Roethenbaugh.
He added that the awareness of obesity also benefits sports and rehydration drinks.
"There will undoubtedly be a proliferation of weight reduction products but drinks are also part of the exercise occasion and this will drive sales."
According to the latest TGI data for April 2003 to March 2004 from research agency BMRB, 27 per cent of Great Britain's adult population are actively trying to lose weight and 21 per cent have used diet food or drink products.
Zenith's 2004 UK Bottled Water Report shows that sales have more than doubled from 990 million litres in 1998 to 2,070 million litres in 2003, the combined result of existing consumers drinking more and new consumers entering the market.