January is the month for new year's resolutions, and top of many of our lists will be to lose that extra flab generated from consuming your body weight in turkey, mince pies and Quality Street. This resolve to shed the pounds has led to a surge in traffic to online diet and fitness sites according to Nielsen/Netratings.

The US internet analyst found that during the week ending 29 December more than 3.5 million people logged on to a range of American health, fitness and nutrition websites. AOL Health alone attracted just over 800,000 visitors, while eDiets.com led the way for diet and fitness sites with 480,000 visitors.

eDiets UK has seen a similar increase in interest since the start of the new year according to MD, Ciaran McCourt. "Dieting is at the top of lots of peoples minds right now, and we have seen a spike in traffic since 1 January," he said.

McCourt believes the reasons behind this growing interest in online diet and fitness sites are manifold. EDiets UK, which has 13,000 paying customers and over 300,000 subscribers who receive regular email newsletters, puts its success down to offering a combination of diet and fitness advice, peer group and expert support, confidentiality and convenience.

"Dieting can be a faddish business so people are always looking for any service that can make it easier. We offer the convenience of a personalised plan that you can access 24/7 no matter where you are," he says.

The paid-for service costs £7.95 per month, with a £29.95 upfront fee for the first nine weeks which McCourt claims makes it around 40 percent cheaper than rival WeightWatchers. He also says that it offers more expert advice than traditional slimming clubs. "Most people who attend WeightWatchers never see a nutritionist," he says, whereas eDiets offers online meetings with nutrition and fitness experts.

Peer group support is provided by online forums which allow dieters to chat while maintaining their anonymity if they wish.