What Is Obesity?

Obesity results from the excessive accumulation of fat that exceeds the body’s skeletal and physical standards. According to the National Institutes of Health (NIH), an increase in 20 percent or more above your ideal body weight is the point at which excess weight becomes a health risk. Today 97 million Americans, more than one-third of the adult population, are overweight or obese. An estimated 5 to 10 million of those are considered morbidly obese.

What is Morbid Obesity?

Obesity becomes “morbid” when it reaches the point of significantly increasing the risk of one or more obesity-related health conditions or serious diseases (also known as co-morbidities) that result either in significant physical disability or even death. As you read about morbid obesity you may also see the term “clinically severe obesity” used. Both are descriptions of the same condition and can be used interchangeably. Morbid obesity is typically defined as being 100 lbs. or more over ideal body weight or having a Body Mass Index of 40 or higher. According to the National Institutes of Health Consensus Report, morbid obesity is a serious disease and must be treated as such. It is a chronic disease, meaning that its symptoms build slowly over an extended period of time.

Causes of Morbid Obesity

The reasons for obesity are multiple and complex. Despite conventional wisdom, it is not simply a result of overeating. Research has shown that in many cases a significant, underlying cause of morbid obesity is genetic. Studies have demonstrated that once the problem is established, efforts such as dieting and exercise programs have a limited ability to provide effective long-term relief.

Science continues to search for answers. But until the disease is better understood, the control of excess weight is something patients must work at for their entire lives. That is why it is very important to understand that all current medical interventions, including weight loss surgery, should not be considered medical cures. Rather they are attempts to reduce the effects of excessive weight and alleviate the serious physical, emotional and social consequences of the disease.

Contributing Factors

The underlying causes of severe obesity are not known. There are many factors that contribute to the development of obesity including genetic, hereditary, environmental, metabolic and eating disorders. There are also certain medical conditions that may result in obesity like intake of steroids and hypothyroidism.

Genetic Factors

Numerous scientific studies have established that your genes play an important role in your tendency to gain excess weight.

  • The body weight of adopted children shows no correlation with the body weight of their adoptive parents, who feed them and teach them how to eat. Their weight does have an 80 percent correlation with their genetic parents, whom they have never met.
  • Identical twins, with the same genes, show a much higher similarity of body weights than do fraternal twins, who have different genes.
  • Certain groups of people, such as the Pima Indian tribe in Arizona, have a very high incidence of severe obesity. They also have significantly higher rates of diabetes and heart disease than other ethnic groups.

We probably have a number of genes directly related to weight. Just as some genes determine eye color or height, others affect our appetite, our ability to feel full or satisfied, our metabolism, our fat-storing ability, and even our natural activity levels.

Environmental Factors

If you have a genetic predisposition toward obesity, then the modern American lifestyle and environment may make controlling your weight more difficult.

Environmental and genetic factors are closely intertwined. Fast food, long days sitting at a desk, and suburban neighborhoods that require cars all magnify hereditary factors such as metabolism and efficient fat storage.

For those suffering from morbid obesity, anything less than a total change in environment usually results in failure to reach and maintain a healthy body weight.


We used to think of weight gain or loss as only a function of calories ingested and then burned. Take in more calories than you burn, gain weight; burn more calories than you ingest, lose weight. But now we know the equation isn’t that simple.

Obesity researchers now talk about a theory called the “set point,” a sort of thermostat in the brain that makes people resistant to either weight gain or loss. If you try to override the set point by drastically cutting your calorie intake, your brain responds by lowering metabolism and slowing activity. You then gain back any weight you lost.

Eating Disorders & Medical Conditions

Weight loss surgery is not a cure for eating disorders. And there are medical conditions, such as hypothyroidism, that can also cause weight gain. That’s why it’s important that you work with your doctor to make sure you do not have a condition that should be treated with medication and counseling.

Am I Morbidly Obese?

Answering this question may give you the courage you need to take the first step. Below are tools you can use to determine if you are morbidly obese and potentially a candidate for weight loss surgery.

There are several medically accepted criteria for defining morbid obesity. You are likely morbidly obese if you are:

  • more than 100 lbs. over your ideal body weight, or
  • have a Body Mass Index (BMI) of over 40, or
  • have a BMI of over 35 and are experiencing severe negative health effects, such as high blood pressure or diabetes, related to being severely overweight
  • unable to achieve a healthy body weight for a sustained period of time, even through medically supervised dieting

Obesity-Related Health Conditions

Obesity-related health conditions are health conditions that, whether alone or in combination, can significantly reduce your life expectancy. A partial list of some of the more common conditions follows. Your doctor can provide you with a more detailed and complete list:

Type 2 Diabetes. Obese individuals develop a resistance to insulin, which regulates blood sugar levels. Over time, the resulting high blood sugar can cause serious damage to the body.

High blood pressure/Heart disease. Excess body weight strains the ability of the heart to function properly. The resulting hypertension (high blood pressure) can result in strokes, as well as inflict significant heart and kidney damage.

Osteoarthritis of weight-bearing joints. The additional weight placed on joints, particularly knees and hips, results in rapid wear and tear, along with pain caused by inflammation. Similarly, bones and muscles of the back are constantly strained, resulting in disk problems, pain and decreased mobility.

Sleep apnea/Respiratory problems. Fat deposits in the tongue and neck can cause intermittent obstruction of the air passage. Because the obstruction is increased when sleeping on your back, you may find yourself waking frequently to reposition yourself. The resulting loss of sleep often results in daytime drowsiness and headaches.

Gastroesophageal reflux/Heartburn. Acid belongs in the stomach and seldom causes any problem when it stays there. When acid escapes into the esophagus through a weak or overloaded valve at the top of the stomach, the result is called gastroesophageal reflux, and “heartburn” and acid indigestion are common symptoms. Approximately 10-15% of patients with even mild sporadic symptoms of heartburn will develop a condition called Barrett’s esophagus, which is a pre-malignant change in the lining membrane of the esophagus, a cause of esophageal cancer.

Depression. Seriously overweight persons face constant challenges to their emotions: repeated failure with dieting, disapproval from family and friends, sneers and remarks from strangers. They often experience discrimination at work, cannot fit comfortably in theatre seats, or ride in a bus or plane.

Infertility. The inability or diminished ability to produce offspring.

Urinary stress incontinence. A large, heavy abdomen and relaxation of the pelvic muscles, especially associated with the effects of childbirth, may cause the valve on the urinary bladder to be weakened, leading to leakage of urine with coughing, sneezing, or laughing.

Menstrual irregularities. Morbidly obese individuals often experience disruptions of the menstrual cycle, including interruption of the menstrual cycle, abnormal menstrual flow and increased pain associated with the menstrual cycle.