Orlistat (Xenical) in the management of obesity.

The term “obesity” implies an excess of adipose tissue (fat) and excess adiposity is a health risk. In most cases it develops in the absence of any underlying disease process. It is always due to greater calorie intake than is expended; the mystery lies in the cause of the energy imbalance. Recently there has been a tremendous surge of interest in understanding the mechanisms controlling energy homeostasis following the identification of the ob gene and its protein product (termed “leptin” from the Greek work “leptos”, meaning thin) by Zhang et al in 1994. The most widely used measurement in clinical practice is the Body Mass Index (BMI); defined as the ratio of the body weight (in kilograms) divided by the square of the height (in metres). Traditionally in the adult, the normal range of the BMI is 20 to 25; a BMI of 25.1 to 29.9 is overweight and a BMI of 30 and above is obese. Recently, for the Asia Pacific region, the recommended normal BMI is 18.5 to 22.5; a BMI of >23 is overweight. A BMI of 23 to 24.9 is regarded as At Risk; 25 to 29.9 is Obese I and >30 is Obese II.