|Info : The Body Mass Index|
How the Body Mass Index (BMI) works
To determine if we are underweight or overweight the BMI looks at our weight in relation to our height. This then falls within a certain range, which is regarded as healthy. Outside that range is regarded as under weight or overweight and not healthy. For example, a person who is six feet tall (182cm) is regarded as healthy if their weight falls between 145 and 182 pounds (67-83 kg). Someone 5 feet 8 inches (172cm) should weigh between 131 and 161 pounds (62-74 kg).
How to calculate your Body Mass Index
You can calculate your own BMI or you can use one of the many web sites with a calculator. If you want to do it yourself, the BMI formula is your weight divided by you height squared, then multiplied by 703, if you are working in pounds. This means for someone weighing 140 pounds who is 5 feet 10 inches (70 ins) tall, the calculation would be 140 divided by 4900 (70x70), which would equal 0.028. You multiply this by 703, which gives you a BMI of 19.68. To do the calculation in kilograms you simply divide your weight by your height squared and forget the 703. For example, someone who weighs 65 kilograms and is 1.78 meters tall would have a BMI of 20.51 (65/1.78x1.78).
If you are not much good at maths and you feel your eyes glazing over when you look at the figures, just go over them again and you will see they are not too hard to work out.
What is your ideal weight?
The World Health Organisation has defined categories of BMI based on evidence of increased risk of chronic disease and mortality. A BMI of 25-29.9 is in the category of overweight, 30-39.9 is obesity and over 40 is morbid obesity. It can be a bit of a shock to find you fit into one of these categories, but it is something we should all know so we can do something about it. What this means is we should all be trying to reach a Body Mass index of under 25 if we want to be in the healthy weight category.
There is some discussion as to how effective the various ways of measuring ideal weight are, but the BMI has become widely accepted. The World Health Organisation and other health authorities use it as a standard in their guide to healthy weight. Many life insurance companies use it as a guide to overweight and underweight in their underwriting decisions. It is a practical way to help us manage our weight so that we stay in that healthy weight range and avoid many of the modern lifestyle diseases. You can use the BMI formula to set your ideal weight target and to keep on track while you are achieving it.