Being overweight or obese means that excess fat is causing health problems.

    It is most commonly measured by Body Mass Index (BMI). Your BMI is your weight (kg) divided by the square (number multiplied by itself) of your height in meters.

    Find your BMI

    Work out your height in metres and multiply the figure by itself.

    Measure your weight in kilograms.

    Divide the weight by the height squared (ie, the answer to question 1). For example, you might be 1.6m (5ft 3in) tall and weigh 65kg (10st).

    The calculation would then be:

    65 / 1.6x1.6 = 24.52

    WHO BMI classification

    Normal BMI between 18.5 and 24.99

    Overweight with a BMI >25

    Obese with a BMI >30

    Note, that with a BMI higher than 21 the risk of chronic disease increases.

    超重或肥胖指過度肥胖正導致健康問題。

    通常采用體重指數（BMI）來衡量。你的BMI指數是你的體重（公斤）除以你身高（米）的平方（身高乘身高）。

    計算你的BMI指數

    測量你的身高，以米為單位，并將數字相乘。

    測量你的體重，以公斤為單位。

    用身高的平方（也就是問題一的答案）除以體重。例如，你可能高1.6米（5英尺3英寸），重65公斤。

    算式即為：

    65 / 1.6x1.6 = 24.52

    世界衛生組織BMI指數分級

    正常BMI指數 18.5至24.99

    超重BMI指數大于25

    肥胖BMI指數大于30

    注意，BMI指數高出正常21個點的罹患慢性疾病的風險也將上升。