Overweight people are in the firing line again. Life insurance companies are increasing premiums up to four fold for fat people. They've always charged more for those of us who over-eat, but during the last year the penalties have got worse.

In moves to tighten the belts further, the life insurers are lowering the weight limits they use to categorise people. This tougher move means that those who are merely overweight and would have previously qualified for a standard premium, are now penalised with higher premiums and the premium rapidly rises the more overweight they believe you are.

Height and weight are just two of the questions you have to answer when you apply for life insurance. From them, the life company calculates your Body Mass Index and if that exceeds the limits they define as acceptable, they might ask for a doctor's report. In bigger cases they might ask you to have a medical examination. If this confirms that your weight is of concern, then you can expect your premium to be loaded by at least 50% and as much as 400% if you're really obese. Recent research shows that around 25% of applicants will experience problems getting life cover due to their weight. In extreme cases the insurer will even refuse the application.

In an acknowledgement of normal middle age spread, the insurance companies do take your age into account when deciding your premium. They accept that people naturally tend to put weight on as they age. If you're young and overweight, however, they'll certainly hit you hard. So overweight and 38 will be hit much harder than overweight and 58.

For example, a non smoking healthy man aged 35 asking for 150,000 level cover over 25 years will currently be quoted 18.77 by Scottish Provident but this could easily jump to 35 if he is overweight and up to 47 if he's obese.

And obesity is certainly a growing problem. Over the last 20 years obesity in adults has rocketed with more than 60% of men and 50% of women being judged as overweight or obese. And signs are that the problem won't improve. In children aged between 2 and 15, 28% of girls and 22% of boys are overweight.

How do you rate on the Body Mass Index?

Calculate your own BMI.

Note your weight in pounds and multiply it by 703.

Divide the result by your height measured in inches

Again divide the resulting number by your height in inches

The result is your BMI

The typical insurance company considers a BMI of between 18.5 and 24.9 to as normal. Above 25 classifies you as overweight. Over 30 and you're obese.

To give you more of a fix on what this means for you, here are the BMI's for twelve famous people:

Under weight

Paula Radcliffe Marathon Runner - 18.0

Victoria Beckham Footballers Wife - 17.0

Jennifer Aniston Actress - 17.5

Normal weight

Alan Shearer Newcastle Footballer - 24.4

Davina McCall TV Presenter - 20.8

Cilla Black Presenter - 20.7

Overweight

Russell Crowe Hollywood Actor - 25.6

Ann Widdecombe MP - 25.1

Charlie Dimmock Gardening Presenter - 26.0

Obese

Norman Schwarzkopf US General - 30.5

Michelle McManus Presenter - 34.4

Dawn French Comedienne - 43.8