"Obesity"

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.[1][2] 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.[3] Obesity increases the likelihood of various diseases,particulary heart disease,type2 diabetes,breathing difficulties during sleep,certain types of cancer,and osteoarthritis.[2] 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.[4][5] 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 [6][7] 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.[8] 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.[2][9]