Are you a healthy weight and size?
 
The best person to decide whether you are a healthy weight is you - if you feel healthy at your current weight, have plenty of energy, and know you are eating healthily and doing plenty of exercise, then great.  If not, you might find it useful to check what the expert guidelines say about your weight and your size.
 
One of the easiest ways to check if you are a healthy weight is to compare it to your height on the chart below.  Find your height at the side and weight at the top or bottom and follow the grid lines to where the two cross, to see what category you fall into:
 
 

Body mass index chart

This chart only works if you are over 18-years-old - for under 18s, there are other charts that are more complicated.
 
What category are you in?
 
Underweight - you may need to put on some weight - see this page for some advice.  If your weight is very low, please contact your GP for advice.
 
OK - Your weight is in the range that is considered the healthiest for your height - which means you are eating the right amount of food to balance out with the amount of exercise you do. 
 
Overweight - Your weight is above the healthiest range for your height.  If you are a serious athlete or body builder and know you have large muscles, this may be why you are in this category.  For the rest of us, the reason for being over-weight is having too much fat on our body.   
 
Fat or very fat - Your weight is well above the healthiest range for your height.  You are actually in the range called obesity - a level in which you have an increased risk for developing heart disease, diabetes, osteoarthritis and high blood pressure.  If your weight is very high, please contact your GP for advice. (Note - we don't really like saying 'fat', but the only chart we could find uses it.)
 

BMI or Body Mass Index
 
A way in which health professionals judge whether a person's weight is healthy for their height is to calculate their body mass index or BMI. 
 
To calculate your BMI, divide your weight in kilograms by your height in metres, squared, so for example, someone who weighs 60kg and is 1.63m tall has a BMI of 60/(1.63x1.63) = 22.6.  Try using the calculator below.  (To convert weight in pounds to kg divide by 2.2, and to convert inches to metres, divide by 39.4)
 
 
Weight (in Kilos) Height (in Centimeters)

BMI

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A healthy BMI for an adult is 20 to 25, under 20 is underweight (under 18.5 very underweight), 25-30 overweight, and more than 30 obese (a medical word for the level at which being overweight becomes a serious health risk).
 
For children and teenagers, you can find a BMI calculator at the site of the UK charity Weight Concern
 

Are you an apple or a pear? 
 
Another way of measuring health risks due to being overweight is by looking at your waist size.  Having too much fat around your waist (being an apple shape, rather than a pear shape) is linked to an increased risk of developing heart disease and diabetes.  Some people with large waists do not feel like they are particularly overweight - as their waist feels quite solid, rather than flabby, however their fat is collecting inside their body, around their organs, which is not healthy!  Measure half way between the top of your hips and the bottom of your ribs, and check out your measurements below:
 
Men -  waist over 94cm or 37 inches = increased risk, over 102cm or 40 inches = high risk (experts say that Asian men have an increased risk if their waist is over 90 cm or 36 inches) 
 
Women -  waist over 80cm or 32 inches = increased risk, over 88cm or 35 inches = high risk.  As a very rough guide, 80cm is a UK high-street size 14-16, and 88 cm is a size 18.
 
If your waist measurement puts you at risk, reducing it by losing weight, will help.