kg ÷ m2 Body mass formula predicts early grave for super-skinny

Dr Marios Kyriazis, one of the few anti-ageing specialists in the UK, said the former Spice Girl, who is 5ft 6in tall and reportedly weighs just over seven stone, has an unhealthy body mass index (BMI) of 17 and needs to change her eating ways quickly if she wants to survive to old age.

Dr Kyriazis added: "You can calculate how long a person has left to live based on their ideal weight, their height and their current age.

"Using these calculations, I have found that Victoria will only live until she's 54.

"To increase her lifespan, she needs to consume more food and more calories."

And Dr Kyriazis warned: "Also, if she continues as she is she will suffer from heart disease, osteoporosis and more age-related illnesses."

Ms Beckham, who admits she keeps sugar cubes in her handbag to suck when she is feeling low in energy, has always denied she has any eating problems.

She said: "There is a massive difference between someone having an eating disorder and someone who watches what they eat.

"Every now and then I go out and eat what I like. But I do try to be quite disciplined about what I eat."

But there are signs the superskinny look is on its way out.

Madrid City Council, which sponsors the Spanish capital's annual fashion week, recently announced it would ban models with a BMI of less than 18.

The move was followed by the organisers of other fashion shows, including the Edinburgh Fashion Festival.

BMI is a measure of weight scaled to height. To calculate BMI, the individual's body weight in kilograms is divided by the square of their height in metres.

A BMI of 18.5 to 25 is considered normal. A BMI of below 18.5 suggests a person is underweight, while a figure of above 30 suggests obesity.

Some experts, however, believe that the BMI's accuracy in relation to actual levels of body fat is easily distorted by such factors as fitness level, muscle mass, bone structure, gender and ethnicity.