Have you heard people talk about their body mass index? Well here is how it's calculated and what it means

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How to Series Measurement of Height/Weight and Body Mass Index (BMI)
Introduction Obesity rates have increased sharply in the UK and are projected to rise still further.
Government initiatives aiming to reduce the national tendency have failed to stop the
increase. Therefore as obesity rates rise it will become more of an issue for OH
professionals as overweight young adults enter the workplace and those already in
employment get bigger. Equipment and environments will have to take into
consideration the size and capability of those who may be in the ‘morbidly obese’
category.
BMI categories
Research shows that risks of disease and incapacity increase with weight gain and
the BMI scales have been used for years as a predictor of future ill health and to help
decide on risk factors.
An individual’s BMI is calculated by dividing the weight in kilos by height in metres
squared.
Therefore a weight of 70 kilos and height 152 cms = 70 ÷ (1.52 x 1.52) = 30.2 BMI
Underweight < 18.5
Ideal 18.5 – 25
Overweight 25 – 30
Obese 30 – 40
Very Obese 40 +
Equipment Tape or wall measure in centimetres
Calibrated weight scales
Method Measure height without shoes
Measure weight without shoes and calculate weight of clothing to be subtracted or
note the clothes worn
Outcome BMI result in ‘normal’ limits or above
Records Record all findings in individual case file
Report fitness for work to employer
Occupational Health
implications
Some occupations require that individuals have specific limits to their weight, which is
linked to the perception of agility and mobility, for example train drivers. Height and
weight measurement is also part of many health promotion exercises and health
screening activities.
Nowadays the issue of obesity linked to specific occupations is fraught with problems
as the BMI calculation takes no account if an individual is particular athletic or
muscular (muscle weighs more than fat). There is also no calculation for pregnancy
or breastfeeding mothers or people who are frail.
For pre-placement in the future there will be more issues with mobility and ergonomics
as the obesity problems developing in childhood begin to manifest in the workplace.
Many employers will look to the OH professional to advise them appropriately on
employment issues and risk assessment principles and also to undertake health
promotion on those most affected as part of a wellbeing programme.
Occupational Health (OH) is seen as a public health speciality with OH nurses on the
third part of the register with the Nursing and Midwifery Council (NMC). Health
promotion initiatives around wellbeing and keeping fit and healthy form part of the

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general philosophy of care within the discipline.
Issues with severe obesity could be covered under the Equality Act so employers may
have to consider reasonable adjustments if the definition of disability is applicable.
Follow up Individual health education and group health promotion advice on healthy eating and
exercise programmes can assist with weight loss or gain for those who are outside the
required parameters
Further Information Go to NHS Choices for a BMI calculator and advice on how to lose weight. There is
also a free app available for I phones and I pads to calculate and monitor weight.
http://www.nhs.uk/Tools/Pages/Healthyweightcalculator.aspx
Go to NICE (National Institute for Health and Clinical Excellence) for research based
methods of dealing with eating disorders and guidance on health promotion initiatives
in the general population
www.nice.org.uk