Why your waist size matters

What's on this page

• Why is the size of your waist important? 
• What’s the best way to measure your waist? 
• How to work out your waist to height ratio 
• What does your waist to height ratio mean? 

Why is the size of your waist important?

The size of your waist can tell you how much fat sits around your belly (abdomen).

Some of this fat sits under the skin (subcutaneous fat). This is the fat you can feel.

Another type of fat (visceral fat) builds up around your organs.

This fat is linked to high cholesterol, high blood pressure and type 2 diabetes.

A larger waist may also mean there is too much fat inside your organs. This can also pose a risk to your health.

For example, if there is excess fat in your liver, it can pump out too much fat and sugar into your blood. This can increase your risk of coronary heart disease and type 2 diabetes.

What’s the best way to measure your waist?

The National Institute for Health and Care Excellence (NICE) recommends using something called the ‘waist to height ratio’ to find out how much fat is stored around your belly.

This compares the size of your waist (the circumference) to your height. You can work out your waist to height ratio at home.

If there is a smaller difference between your waist and your height, this means that your waist is larger.

How to work out your waist to height ratio

1. Find the bottom of your ribs and the top of your hips.
2. Wrap a tape measure around your belly at the halfway point between them (just above the belly button).
3. Make sure it’s pulled tight but is not digging into your skin.
4. Breathe out naturally and make a note of where the tape measure reaches all the way around. This can be in inches or centimetres.
5. Measure or work out your height in inches or centimetres (use the same unit you used to measure your waist).
6. Divide your waist by your height.

For example, if your waist is size 96.5cm and your height is 170cm, you need to divide 96.5cm by 170cm, which equals 0.57. This is your waist to height ratio. 

• Use this NHS tool to calculate your waist to height ratio

The 'string challenge'

If you do not have a tape measure, you can use a piece of string instead:

1. Use the piece of string to measure your height from the bottom of your feet to the top of your head.
2. Cut or mark the string to the same length as your height, and then fold it in half.
3. Wrap the folded string around your waist.

If you cannot completely wrap the folded string around your waist, this suggests you are carrying too much fat around your waist.

What does your waist to height ratio mean?

The more excess fat you have around your belly, the higher your waist to height ratio will be, and the greater your risk of health problems.

If your ratio is 0.6 or above, you are at the highest risk, and if it’s between 0.5 and 0.59 you are at increased risk. In both cases you will likely need to lose weight to reduce your risk of heart and circulatory diseases.

If your ratio is 0.4 to 0.49 then you are in the healthy range.

If you are worried about your waist size, speak to your nurse or GP. 

• Discover 5 steps to sustainable weight loss.

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