It's no good expecting a man to eat cabbage soup

Dr Ian Campbell

Instead, it relies on gently persuading male couch potatoes to gradually reduce the amount of food that they eat.

The key is to eat more vegetables, consume less saturated fat - like lard - cut down on alcohol, and forget about snacks between meals.

Dr Campbell said that by following his programme it should be possible to trim four inches off the average male beer gut in 12 weeks.

But he said it was important that individuals felt free to progress at their own pace.

Dr Campbell has worked out that if only one in 200 overweight British men stick with the programme, the weight of the nation would drop by more than 1,000 tonnes.

Good for health

According to National Audit Office figures, sustained weight loss of five to 10 kilograms (11lbs - 22lbs) can reduce the chances of fatal heart disease by 9%, and can cut the chances of cancer by more than a third.

Dr Campbell, a GP who runs an obesity clinic in Nottingham and chairs the National Obesity Forum, devised Fatmanslim after becoming frustrated at the lack of help given to men who need to lose weight.

He said: "Less than 1% of the people who seek help from standard commercial weight loss agencies are male, yet many men are overweight.

"Men are reluctant to seek help, and there is a lack of provision in the NHS to help them.

"You have to adopt a different approach with men. It's very important not to be proscriptive - men like being in control and don't want to be told what to do.

"It's no good expecting a man to eat cabbage soup, and everyone knows quick fix diets don't work anyway."

The Fatmanslim kit includes interactive elements designed to identify an individual's bad habits and the reasons other than hunger why he might be over-eating - such as boredom, stress or social pressure

Participants are also able to consult experts via a members-only website.

The kit, which costs �84, is only available by mail order from Nottingham-based FMS Healthcare, which already supplies slimming programmes for women.