Sunday, October 24, 2010
Obesity is a medical condition in which excess body fat has accumulated to the exttent that it may have an adverse effect on health,leading to reduced life expectancy and /or increased health problems. Body mass index (BMI),a measurement which compares weight and height,defines people as overweight(pre-obese) when their BMI is between 25kg/m2 and 30kg/m2. Obesity increases the likelihood of various diseases,particulary heart disease,type2 diabetes,breathing difficulties during sleep,certain types of cancer,and osteoarthritis. Obesity is the most commonly caused by a combination of excessive dietary calories,lack of physical activity,and genetic susceptibility,although a few cases are caused primarily by genes,endocrine disorders,medications or psychiatric illnes.Evidence to support the view that some obese people eat little yet gain weight due to a slow metabolism is limited;on average obese people have greater energy than their thin counterparts due to the energy required to maintain an increased body mass. The primary treatment for obesity dieting and physical exercise.To supplement this,or in case of failure,anti-obesity drugs may be taken to reduced appetite or inhibit fat absorption.In severe cases,surgery is performed or an intragastric balloon is placed to reduced stomach volume and /or bowel lenght,leading to earlier satiation and reduced ability to absorb nutrients from food  Obesity is a leading cause of death worldwide,with increasing prevalence in adults and children,and authorities view it as one of the most serious public health problems of the 21st century. Obesity is stigmatized in much of the modern world (particulary in the Western World),though it was widely perceived as a symbol of wealth and fertility at other times in history,and still is in some parts of the world.