Body Mass Index (BMI) and health
A risk factor for many diseases - including cardiovascular disease, fatty liver disease, and diabetes - is weight. The Body Mass Index, calculated by dividing a person's mass (in kilograms) by the square of their height (in metres). is calculated using a person's weight and their height. Your BMI is an indication of whether your body mass is at a healthy level in proportion to your height. A very high BMI means that someone is overweight or even obese.
There are different charts for adults and young people. The BMI which has been calculated is compared to the appropriate chart in order to discover whether the person is underweight, a healthy weight, overweight or obese.
Question
A 16 year old boy has a body mass of 65 kg and is 1.70 m tall. Calculate his BMI.
Use the equation body mass index (BMI) = \( \frac{body~mass~in~kilograms} {(height~in~metres)^2}\)
BMI = \( \frac{65} {1.70 \times 1.70}\)
= \( \frac{65~kg} {2.89~m^2}\)
= 22.5 kg/m2
Using a BMI chart for boys aged 2-20, a BMI of 22.5 kg/m2 is in the 'healthy' range.
BMI and disease
People with a very high body mass index (BMI) are defined as obese.
The medical term for being very overweight, owing to the excessive accumulation of body fat. leads to high The force of blood against the artery walls. and the build-up of fatty deposits in the arteries, which lead to Disease relating to the heart and the blood vessels.. It also increases the likelihood of developing A serious disease in which the body is unable to regulate blood sugar., another risk factor for cardiovascular disease.
Being obese - with deposits of Fat or oils, composed of fatty acids and glycerol. in the abdomen - increases blood pressure beyond normal levels and increases levels of blood lipids.
Type 2 diabetes
Body fat also affects the body's ability to use A hormone that regulates the level of sugar in the blood and can be produced by genetically modified bacteria..
Type 2 diabetes is where the body's cells lose their sensitivity to insulin - they no longer respond, or respond less effectively, to the insulin that's produced. This causes glucose levels in the blood to rise to dangerous levels.
Obesity accounts for 80 to 85 per cent of the risk of Type 2 diabetes. Rising obesity is linked with 'western diet' - a diet that includes energy-rich 'fast foods' and an inactive lifestyle. The bar charts show the increased risk of developing Type 2 diabetes associated with people's body mass index (BMI).
There is no cure for Type 2 diabetes, but it may be possible to control it by diet and exercise. The risk of developing cardiovascular disease and Type 2 diabetes can be reduced by eating a balanced diet, with unrefined, unprocessed, 'whole foods', and taking regular exercise.
