Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health. Numerous studies have demonstrated a linear relationship between the level of obesity and both morbidity and mortality and obesity is one of the leading preventable causes of death worldwide. So, we now talk of someone suffering from obesity, the definition of which is objective, rather than being obese which is both descriptive and subjective.

Two thirds, or approximately 65%, of the adult population in western societies are overweight with half of this group suffering from obesity. Quite apart from the effects on our physical health it takes an enormous toll on our psychological health with a huge number of people simply wishing regularly that they could be in the normal range. Thankfully this is eminently achievable when armed with the right information

There is a wide range of medical disorders that have a higher incidence in people who are suffering from obesity, in particular type two diabetes, certain cancers in particular the common ones such as breast and bowel, hypertension or high blood pressure, cardiovascular disease such as heart attacks and strokes and osteoarthritis which is wear and tear on our joints. All of these conditions and others, are covered extensively in the section entitled avoid illness.

Body fat can be measured in a number of ways but for the purposes of definition body mass index (BMI) is used. It has a close relationship to both body fat as measured as a percentage (PBF) and as a weight (total body fat - TBF). Whilst there are no absolutes with regard to PBF a healthy male adult has approximately 15-18% and females 18-25%.

BMI is calculated by taking the weight of the subject in kilograms and dividing this by the square of the height in metres. A BMI of between 18.5 and 25 is normal. Below 18.5 is classified as underweight. Between 25 and 29.9 the subject is classified as overweight, between 30 and 34.9 they are classified as having class one obesity, between 35 and 39.9 class two obesity or severe obesity and over 40 as class three obesity or morbid obesity.

The use of BMI has its critics but overall, for 95% of us, it is an accurate and importantly practical way of assessing obesity. The main detractors are generally ones who find the truth inconvenient and this is based on feelings of guilt which need to be overcome in the management of this disease. And like any disease there is always help in treating it!