Although, monitoring your weight is useful to keep you on track, and to highlight whether or not you are maintaining weight, piling it on, or successfully slimming down, assessing your weight isn’t as simple as just stepping on the scales. A weight of 75kg (11stone 11lb) may be ideal for one person but seriously overweight for another, depending on how tall you are, and whether or not you have a lot of lean muscle bulk.
A more accurate measure was developed to estimate body fat stores, which uses the relationship between your height and weight. This is known as the body mass index, or BMI, and is calculated by dividing your weight (in kilograms) by your height (in metres) and by your height in metres again:
BMI = Weight (Kg) / Height (M) X Height (M)
You don’t have to work out your Body Mass Index yourself, as there is a free BMI calculator at the end of this post to crunch the numbers for you.
What is a healthy BMI?
According to the World Health Organisation, a healthy body mass index range (BMI) is 18.7 to 23.8 Kg/M2 for women, and 20 – 25 Kg/M2 for men.
Working backwards, the BMI of 18.5 to 24.9 can be used to calculate the ideal healthy weight range according to your height, as shown here.
Ideally, you want to be in the healthy weight range for your height, as this is associated with the lowest risk of a number of long-term health conditions such as type 2 diabetes, high blood pressure, heart attack and stroke.
BMI is not a perfect measure
Although BMI is a useful guide, it’s still not a perfect measure of body fat. It tries to squeeze a three-dimensional object – your body – into a two-dimensional equation. BMI calculations are not accurate for people who are less than five feet tall, or for those with a lot of muscle mass. In fact, BMI tends to overestimate body fat in athletes and body builders with a muscular build, and to underestimate body fat in older people and those who have lost muscle mass.
BMI also tells us nothing about where you store your excess fat. People who store excess fat around their internal organs (visceral fat), giving them a large waist, have significantly more health problems than those storing fat elsewhere.
Use the following calculator to work out your BMI using either metric or imperial measures.
Supplied by BMI Calculator USA