General Description of Obesity and its associated conditions

Obesity is a chronic condition defined by an excess amount of body fat. Body mass index (BMI) is a term routinely used by physicians and researchers to describe and calculate a person's body weight, taking into account one's height to determine a person's obesity or general overweight/underweight condition. The BMI equals a person’s weight in kilograms divided by height in meters squared (BMI = kg/m2). For adults, a BMI of 30 or more is considered a state of obesity and a BMI greater than 40 is considered to be a state of severe obesity. Approximately one in three Americans is obese and the incidence of obesity has doubled since 1991.

Obesity is more than a cosmetic concern for it is associated with a number of diseases that can harm one’s health. Obesity increases the risk of developing a number of chronic disease including: adult onset diabetes, high blood pressure, high cholesterol, heart attacks, stoke, chronic liver disease, congestive heart failure, cancer, gallstones, gout, osteoarthritis, sleep apnea and pickwickian syndrome.

The balance between calorie intake and energy expenditure determines a person’s weight. When intake of calories exceeds calories burned by the body, this net positive energy is stored as fat, resulting in weight gain and potential obesity. Likewise, when there is a net negative calorie balance this result in weight loss. The most common causes of obesity are overeating and physical activity. At present, we know that there are many factors that contribute to obesity (such as genetics, overeating, slow metabolism, physical inactivity, medications, psychological factors and certain diseases), some of which have a genetic component.

Concern over obesity is directed not only at how much fat a person has but also where that fat is located in the body. The pattern of body fat distribution differs in men and women. Women typically collect fat in their hips and buttocks, giving their figures a pear shape. Men, on the other hand, usually collect fat around the belly, giving them more of an apple shape. Fat located in the belly or visceral cavity is considered more harmful than fat located elsewhere and is considered to be closely liked to many disease associated with obesity. The measurement that physicians use to determine body fat distribution - and by extension, risk of obesity - is called the waist-to-hip ratio. To find out a person’s waist to hip ratio, measure the waist at its narrowest point, and then measure the hips at the widest point. Divide the waist measurement by the hip measurement. Women with waist-to-hip rations of more than 0.8 and men with waist-to-hip ratios of more than 1.0 are apples with excessive visceral fat, thus at further risk from potential complications stemming from obesity.

In a world where obesity-increasingly occurring in children and teenagers--is more prevalent than ever, the need to be educated about weight management is one of the most important concerns all people should have about their health.

Reviewed by a Cleveland Clinic medical professional.

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