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Body Mass index

What does my score mean?

Compare your scores with the following table:

Classification BMI Score South Asian Score
Underweight Under 18.5 Under 19
Normal Weight 18.5 to 24.9 19 to 22.9
Overweight 25 to 29.9 23 to 27.9
Obese 30 and over 28 and over

These ranges are only for adults. If you’re concerned about your child’s weight, contact your GP.

What is Body Mass Index?
BMI is a measure that most people can use to check if their weight is healthy for their height. However, it is important to note that muscle is heavier than fat and this needs to be borne in mind when interpreting BMI of athletic/muscular individuals

Overweight BMI
If your BMI is 25 or more, you should think about losing weight as being overweight or obese can increase your risk of health problems, such as heart disease, stroke, type 2 diabetes, some cancers, kidney disease and high blood pressure (hypertension)

Underweight BMI
If your BMI is less than 18.5, you may want to talk to your GP about gaining weight. Being underweight can increase your risk of other health problems, such as brittle bones (osteoporosis), absent periods in women and iron deficiency (anaemia).

Weight Loss
There are 3 main aims when considering weight loss:
• To prevent further weight gain
• To gradually lose weight through a combination of a calorie-controlled diet and regular exercise
• To avoid regaining any lost weight

Do – today
You can take four actions today to start your journey towards a healthy weight:
• Swap an unhealthy snack for something healthier. Many snacks, such as chocolate, biscuits and crisp are high in fat and sugar and supply calories that we don’t need. Why not opt for a piece of fruit or a slice of malt loaf with a low-fat spread.
• Swap a sugary drink for a sparkling water with a slice of lemon. Don’t forget that alcohol is also high in calories, so cutting down could help you to control your weight.
• Next, find a way to fit just one extra walk into your day. Fast walking is a way to burn calories, and you can often fit this into your daily routine.
• Make sure you have breakfast and see if you can you make it healthier, using the foods you have at home.

Do – this week
There are four actions you can take this week:
• First, plan a healthy weekly shop. Eating a balanced diet often starts with having the right foods at home.
• Everyone likes a treat occasionally such as a pizza or a takeaway. Swap your treat for a healthier, homemade alternative as you can make lower calorie versions of many of your favourite meals.
• Next, commit to one more way to increase your level of physical activity. It’s recommended that adults between 19 and 64 get at least 150 minutes of moderate-intensity aerobic physical activity. For example, fast walking or cycling.
• Lastly, identify this weeks’ danger zones. These are times when you might find yourself eating lots of foods that are high in fat and sugar, perhaps because you are eating out or simply because you’re tired or stressed. Plan ahead so that you can limit those foods. But don’t be too strict; an indulgence from time to time is fine.

1. ACSM (2013) ACSM’s Guidelines for Exercise Testing and Prescription. Lippincott Williams and Wilkins Health, Baltimore.
2. WHO Experts Consultation (2004) Appropriate Body Mass Index for Asian Populations and it’s Implications for Policy and Intervention
Strategies. Lancet. 363(9403), 157-163.