Obesity has reached epidemic proportions in the United States. One in three Americans is obese. The prevalence of obesity in children has increased markedly, with approximately 20%-25 % of children either overweight or obese. Obesity is also increasing rapidly throughout the world, and the incidence of obesity nearly doubled form 1991 to 1998.
In 2004, the U.S. Centers for Disease Control and Prevention (CDC) ranked obesity as the number one health risk facing America.
Obesity currently results in an estimated 400,000 deaths a year in the United States and costs the national economy nearly $122.9 billion annually.
The definition of obesity varies depending on what one reads, but in general, it is a chronic condition defined by an excess amount body fat. A certain amount of body fat is necessary for storing energy, heat insulation, shock absorption, and other functions.
Obesity also increases a person’s risk for developing serious obesity-related health conditions such as diabetes, heart disease , hypertension, metabolic syndrome, and polycystic ovary syndrome.
In the United States, roughly 300,000 deaths per year are directly related to obesity, and more than 80% of these deaths are in patients with a BMI (body mass index, which will be discussed later in this article) over 30. For patients with a BMI over 40, life expectancy is reduces significantly (as much as 20 years for men and 5 years for women ).
Overweight and obesity are major risk factors for a number of chronic diseases, including diabetes, cardiovascular diseases and cancer and while it was once an issue only in high income countries, overweight and obesity has now dramatically risen in low- and middle-income countries.Such countries are now facing a "double burden" of disease, for while they continue to deal with the problems of infectious disease and under-nutrition, they are also experiencing a rapid upsurge in chronic disease risk factors such as obesity and overweight, particularly in urban settings.
Weight gain and obesity are caused by consuming more calories than the body needs – most commonly by eating a diet high in fat and calories, living a sedentary lifestyle, or both.
However, the imbalance between calories consumed and calories burned can also be caused by a number of different physiological factors, including genetic and hormonal problems related to deficiencies in internal body functions.
It is important to remember that obesity is not always caused by simple behavioral issues. In fact, endocrine researchers are leading exciting new research into the internal mechanisms that control metabolism, appetite, and satiety from food.
Under-nutrition and obesity often exist side-by-side within the same country, the same community and even within the same household and this double burden is caused by inadequate pre-natal, infant and young child nutrition followed by exposure to high-fat, energy-dense, micronutrient-poor foods and lack of physical activity.
The normal amount of body fat (expressed as percentage of body fat) is between 25%-30% in women and 18%-23% in men. Women with over 30% body fat and men with over 25% body fat are considered obese.
Sugar should be regulated in the same way as alcohol and tobacco because its increasing use in processed foods poses a significant danger to public health, according to a group of scientists. They advocate controlling sales to children under 17 and taxing sugary foods.
Sugar, they argue, is as toxic to the liver as alcohol and overconsumption is at the root of growing public health problems including obesity and certain types of liver disease.