BMI health check Aim of activity To understand what is a healthy Body Mass Index (BMI) score, how to calculate your own, and the role of exercise and diet on your BMI. Live Long & Prosper theme Healthy living Skills for Life covered Numeracy Learning outcomes By the end of the session, participants will be able to: Explain what Body Mass Index means and why it matters Calculate their own BMI score and know whether this is within the healthy range – and the implications if it is too high or too low Use the resources given to work out a plan of action to change their BMI to within the healthy range Resources required Weighing scales and tape measure (metric) Pen and paper (for noting numbers) Rulers or other flat-edged object (to read off scores on a chart) Calculator BMI chart – available online at An inflatable toy and a picture of a heavy garden ornament Flip chart Introduction: What BMI means and why it’s useful (5 minutes) Go through the learning outcomes. Explain what BMI means and why it’s useful using the ‘BMI health check fact sheet’.
BMI health check Main content: How to work out a BMI (15minutes) Give a light hearted demonstration of the BMI calculation. 1. Measure the inflatable toy’s height in metres – write on flip chart 2. Multiply the figure by itself – this is the height squared – write on flip chart 3. Measure the dolls weight in kilograms – write on flip chart 4. Divide the weight by the height squared – step 3 divided by step 2 E.g. if the toy is 1.10m tall and weighs 3 kg the calculation is: 1.10 x 1.10 = kg divided by 1.21 = 2.5 – a worryingly low BMI Show everyone on the chart how concerned you are about the inflatable toy and point out some of the problems associated with being very underweight. Refer to handout. Using the picture, repeat the process for the garden ornament. If the garden ornament is 1m tall and weighs 50kg the calculation is 1 x 1 = 1 50 kg divided by 1 = 50 = 50 – an incredibly high BMI Oh dear, the garden ornament is in trouble. Point out the serious health issues about being so overweight. Refer to handout. Top Tip! Practice your calculations first and have them written out, as it can be very difficult to remember when you have lots of eager faces looking at you! If you are feeling brave, now demonstrate the calculation with your own weight or height! If participants feel comfortable doing so, give them the opportunity to work out their own BMI. Encourage people to work in metres and kilograms, although most charts have both metric and imperial measurements. Have tapes and weighing scales handy if measurements need to be checked. Help people with any calculations needed. NB: Many people may be self-conscious and may not want to weigh themselves in public. The handout has instructions to take home. Simple Conversions 1 stone = 6.5kg1 inch = 2.5cm 1 foot = 30cm1 pound =.5 kg
BMI health check Conclusion/Review (5 minutes) Summarise the session using the notes in the handout. Direct participants to further information on BMI and health (see further resources below). Where to go for further information For information on BMI and health visit: For information on becoming healthier: The Adult Core Curriculum has information on numeracy and literacy: The BBC Skillswise website can help with multiplication and division: For advice on addressing literacy and numeracy issues in the workplace: - find out about Government support for training, or to arrange a visit from a skills broker For more information on Skill for Life for individuals:
BMI health check Fact sheet Body Mass Index (BMI) is a quick measure you can use as a guide to see whether you are the recommended weight for your height. Basically, the taller you are the more body you have over which to spread your weight. Your BMI will give you some idea whether you need to lose (or gain) weight. As we’re all different, the BMI is given as a range rather than an exact weight for your height. BMI can vary depending on the size of a person’s frame and may vary slightly depending on gender. Putting it simply, if we eat more food than we burn off through exercise we will gain weight, and if we burn more than we eat, we lose weight. If you eat the equivalent of an extra bag of crisps per day you will gain a stone in weight in a year. In the UK, about two in three adults are now overweight or obese. Of these, more than one person in five is obese (at least kgs or two to three stone overweight) putting their health at considerable risk. Diseases caused or worsened by being obese include: Cancer Heart disease Diabetes Osteoarthritis The National Audit Office in 2001 concluded that obesity could shave an average of nine years from our lifespan. People with a BMI between 19 and 22 live the longest! If your BMI is too low and you are female, your periods may stop, you may become anaemic and later in life suffer from diseases such as osteoporosis. If your BMI is higher than it should be, there are lots of things you can do to bring it down. This will make you look and more importantly feel much better – and be healthier too. BMI is only one measure though and you may have other factors you need to consider, such as other people in your family suffering from heart disease, for example, that mean you need to be more careful about your health and fitness. Even if your BMI shows that you are a healthy weight, it is always worthwhile becoming healthier through doing more exercise and eating better. Make a commitment to one thing you will do differently as a result of finding out your BMI. Ideas might be to get a pedometer and try for 10,000 steps a day. You could try filling half of your plate with greens and keeping pasta/potatoes portions to the size of your clenched fist. If you can’t give up chocolate try dark chocolate rather than milk. You could walk your dog every day or become very popular by offering to walk someone else’s dog! If it’s fun you are more likely to stick to it.
BMI health check Working it out How to work out your BMI There are two things that you need to work out your BMI: Your height Your weight Weigh yourself and note your weight. Ask someone to help you find your height, if you don’t know it already and make a note of it. You can calculate your BMI using a calculator. Work out your height in metres and multiply the figure by itself (height x height) or height squared. Work out your weight in kilograms. Divide your weight by your height squared. The answer is your BMI. Example If you are 1.6m (5ft 3in) tall and weigh 65kg (10st 3lb) the calculation would be: 1.6 x1.6 = 2.56 (height squared) 65 divided by 2.56 (weight divided by height squared) BMI = What does your BMI mean? Your BMI calculation (ranges taken from the National Audit Office) means the following: Under 18.5Underweight Healthy Weight 25 – 30Overweight 30 – 40 Obese Over 40Severely obese An easier way to find your BMI is to use a Body Mass Index chart. (You can find a chart Find your height down the left side of a BMI chart. Using a ruler, place it across the chart so that the height can be seen on the left, with all the figures along the edge of the ruler from left to right. Using a second ruler, look along the figures from left to right until you find your weight. At the point where your weight crosses your height, place the ruler so that it forms a cross with the first ruler. Look at the BMI score where the top of the second ruler falls – this is your BMI. Make a note of your BMI and the colour in which it fell. Green is good. If your BMI is below this you are underweight which is unhealthy. If you’re in the yellow zone you’re overweight and need to take some action. If you’re in the orange zone (with your BMI over 30) you are risking your health. You might want to see your GP about further help in tackling this.