Definition of Obesity
Obesity makes the news all over the world – according to many experts we are in the midst of an “obesity epidemic”. I want to show you how you can tell whether you or your loved ones are part of the growing trend in obesity and offer some advice on what you can do about it.
The medical definition of obesity is that you have a
Body Mass Index (BMI)
of more than 30. Here's how you calculate your Body Mass Index:
Weight in kilograms / height in metres2
For the less "formula minded", to calculate your BMI, follow these three steps.
1. Work out your height in metres and multiply the figure by itself
2. Measure your weight in kilograms
3. Divide the weight by the height squared (the answer to Q1)
For example, you might be 1.6m (5ft 3in) tall and weigh 65kg (143lbs). The calculation would then be:
1.6 x 1.6 = 2.56. BMI would be 65 divided by 2.56 = 25.39.
If the result you get is greater than 25 you fall into the “overweight” category and over 30 you fall into the obese category.
However the real definition of obesity is that your weight has the potential to seriously affect your health. With an increase of BMI your chances of suffering with life-threatening diseases increases. These diseases include:
Coronary Heart Disease
Certain types of cancer.
The BMI measurement is limited
In certain circumstances a high BMI doesn't necessarily indicate you're at greater risk of health problems related to your weight.
This is especially true if your body is high in muscle weight. The BMI formula cannot account for people with large amounts of muscle, and assumes everyone has the standard muscle to weight ratio. In reality this ratio can differ quite a bit from person to person.
For example, Arnold Schwarzenegger, when he won the Mr. Universe bodybuilding title would have qualified as obese on the BMI table because he weighed so much relative to his height.
However his weight was composed of an awful lot of muscle and not much fat at all.
You don't have to be a bodybuilder to have a strange result on the BMI scale:
A friend of mine who used to be a national level competitive swimmer (and is still in great shape today) calculated her BMI and got a result of 26, placing her in the overweight category.
She got worried that she'd become badly out of shape. However using the US Navy's Body Fat Calculation Tool
US Navy's Body Fat Calculator
we worked out that she was actually in the athletic range for body fat level, with a relatively low level of body fat, and therefore at low risk of the dangers of obesity. Even though she hadn't competed in the pool for some years, she still retained a higher level of muscle mass than average, which is an extremely healthy state for your body to be in.