Obesity is defined as excess adipose tissue. There are several different methods for determining excess adipose (fat) tissue; the most common being the Body Mass Index (BMI) (see below). A fat cell is an endocrine cell and adipose tissue is an endocrine organ. As such, adipose tissue secretes a number of products, including metabolites, cytokines, lipids, and coagulation factors among others. Significantly, excess adiposity or obesity causes increased levels of circulating fatty acids and inflammation. This can lead to insulin resistance, which in turn can lead to type 2 diabetes.
The biology of food intake is very complex, involving olfaction (smell), taste, texture, temperature, cognitive and emotional responses and metabolic/autonomic information, which signal the brain to initiate or cease eating. Recent scientific studies have identified several substances that act on the brain to signal a need for an increase in food intake. Likewise, several substances have been identified that signal the brain to decrease food intake.
Obesity is a disease that affects more than one-third of the U.S. adult population (approximately 78.6 million Americans). The number of Americans with obesity has steadily increased since 1960, a trend that has slowed in recent years but shows no sign of reversing. Today, 69 percent of U.S. adults are categorized as being affected by obesity or having excess weight.
According to the CDC, an estimated 112,000 excess deaths per year are associated with obesity. Obesity puts individuals at risk for more than 30 chronic health conditions. They include: type 2 diabetes, high cholesterol, hypertension, gallstones, heart disease, fatty liver disease, sleep apnea, GERD, stress incontinence, heart failure, degenerative joint disease, birth defects, miscarriages, asthma and other respiratory conditions, and numerous cancers.
The healthcare costs of American adults with obesity amount to approximately $190 billion per year. Discrimination and mistreatment of person with obesity is widespread and, sadly, often considered socially acceptable.
Obesity is increasing around the world. High body mass index now ranks with major global health problems such as childhood and maternal under-nutrition, high blood pressure, high cholesterol, unsafe sex, iron deficiency, smoking, alcohol and unsafe water in total global burden of disease.
For people with obesity, weight loss based solely on lifestyle changes can be very difficult to achieve and even more challenging to maintain. Supporting strategies, such as obesity medications, can be important tools for effectively treating obesity in some individuals. Given the complex nature of the disease, no single drug is likely to fix the epidemic. Additional research and development efforts are needed for obesity treatments – as there are more than 100 drugs available for related diseases, like hypertension, but only 6 medications approved for the long-term treatment of obesity.
What Is BMI?
Body Mass Index (BMI) is a mathematical calculation involving height and weight, irrespective of family history, gender, age or race. BMI is calculated by dividing a person’s body weight in kilograms by their height in meters squared (weight [kg] height [m]2) or by using the conversion with pounds (lbs) and inches (in) squared as shown below, This number can be misleading, however, for very muscular people, or for pregnant or lactating women.