Extract:

Literature review for Personal & Professional Skills module: Secret of a Healthy Heart

It is estimated by the World Health Organisation (WHO) that there are currently over one billion adults overweight, with nearly a third of them obese. At present the method of defining whether somebody is overweight or not is to use the Body Mass Index (BMI). This is a simple equation of the weight in kilograms divided by the height in metres squared (kg/m2). The mean adult BMI level is between 22 and 27 kg/m2, varying between different areas of the world (WHO, 2005). In England nearly two thirds of the population are classified as either overweight, BMI > 25, or obese, BMI > 30, with a rate of growth of nearly 400% over the last 25 years. This means that soon this will be the main cause of early death, putting it above smoking (House of Commons Health Committee, 2004). Within Europe, England has one of the worst figures for obesity (see figure 1); also there are generally a higher percentage of men than women who are overweight or obese. It is therefore very important to be able to measure obesity.

The most accurate and expensive methods for calculating the amount of fat on the body are by calculating the body density from the mass and volume, or by calculating the water content of the body, because fat does not contain any water, or by using a scanning technique called Dual energy Xray absorptiometry (DXA) to measure the composition of the body (ORIC, 2004).

Looking at the patterns of the distribution of fat is also important in assessing the health risks associated with obesity. This can be achieved by using computed tomography (CT) or magnetic resonance imaging (MRI) to produce an accurate picture of the body's tissue (ORIC, 2004). There are also alternative quicker and cheaper methods, such as measuring the thickness of skin fold, also know as the 'pinch an inch' test, or the bioelectrical impedance analysis (BIA), which can be used to estimate fat distribution. Briefly, the bioelectrical impedance analysis test measures the impedance of an electric current through the body fluids contained mainly in the lean and fat tissue (Ward L, 2005). Although both methods are less accurate, they are still a better measure than the BMI.

Other factors to consider are the different types of fats that are found in varying amounts around the body. The volume and location of the fat can be a good indicator towards the potential of increased metabolic risk (Kissebah, 1982). Being overweight or obese can lead to adverse metabolic effects on blood pressure, cholesterol, triglycerides (blood fats), diabetes and hypertension, as well increasing the risk of getting cancer. A larger waist, also described as abdominal obesity, is attributed as the main area of obesity associated with the increased risk of developing cardiovascular problems (Thomas, 2004).