Obesity means having too much body fat. It is different from being overweight, which means weighing too much. The weight may come from muscle, bone, fat and/or body water. Both terms mean that a person's weight is greater than what's considered healthy for his or her height.
Obesity occurs over time when you eat more calories than you use. The balance between calories-in and calories-out differs for each person. Factors that might tip the balance include your genetic makeup, overeating, eating high-fat foods and not being physically active.
Being obese increases your risk of diabetes, heart disease, stroke, arthritis and some cancers. If you are obese, losing even 5 to 10 percent of your weight can delay or prevent some of these diseases.
Obesity is a serious disease with symptoms that build slowly over an extended period of time. The National Institutes of Health (NIH) define morbid obesity as:
- Being 100 pounds or more above your ideal body weight, or
- Having a Body Mass Index (BMI) of 40 or greater, or
- Having a BMI of 35 or greater and one or more co-morbid condition.
The disease of morbid obesity interferes with basic physical functions such as breathing or walking. Long-term implications of the disease include shorter life expectancy, serious health consequences in the form of weight-related conditions such as type 2 diabetes and heart disease, and a lower quality of life with fewer economic and social opportunities.
Obesity is a serious public health issue in the U.S. It is estimated that more than 31 million U.S. adults are living with morbid obesity and may qualify for bariatric surgery based on NIH guidelines.
The presence of obesity increases the risk of a number of medical conditions, including cancer. A co-morbid condition is a health condition related to a primary disease such as obesity.
There are many health conditions related to morbid obesity, but some of the most common are:
- Type 2 diabetes, which can lead to heart disease, kidney failure, blindness, amputation of the feet or legs, and nerve damage
- Heart disease, such as hardening of the arteries, heart attack, and angina
- High blood pressure, which can lead to heart disease, stroke, kidney failure, and vision loss
- High cholesterol, which can lead to heart disease, stroke, and kidney failure
- Obstructive sleep apnea has been associated with high blood pressure
- Acid reflux/GERD, which can lead to esophagitis, Barrett’s esophagus, and esophageal cancer (adenocarcinoma)
- Osteoarthritis and joint pain, which can lead to loss of mobility
- Stress urinary incontinence
- Female reproductive health disorder, which can lead to infertility and sexual dysfunction
An emerging body of literature demonstrating relationships between maternal obesity and structural birth defects, including increased risk of spina bifida and heart defects.
These conditions occur more frequently in people with morbid obesity. Mortality rates from many of these conditions are also higher among people with morbid obesity.
There are several different bariatric surgery procedures, but the two general ways in which they work are restriction and malabsorption.
Restriction limits the amount of food you can eat. Whether it is a gastric banding device around the stomach or a surgically-created, smaller stomach pouch, restriction ensures that the patient feels satisfied with less food.
Malabsorption limits the number of calories and nutrients your body can absorb. During malabsorptive procedures, the surgeon reroutes the small intestine so that fewer calories and nutrients are absorbed.
Commonly performed bariatric procedures include:
- Gastric bypass
- Gastric banding
- Sleeve gastrectomy
- Biliopancreatic diversion with duodenal switch
Only you and your surgeon can decide if surgery is right for you.
Diet & Exercise
To lose weight, your body must burn more calories than you eat and/or drink. A diet plan should be based on your health and lifestyle needs, and would include reducing the number of calories you take in. If you are considering this option, speak with your primary care physician about nutritional guidelines, and keep in mind that many bariatric programs also offer medically supervised weight loss programs.
Frequent and regular physical activity is beneficial to most anyone—whether they are pre- or postsurgery. Generally, an exercise program includes cardiovascular exercise such as walking, swimming, or cycling, strength training using resistance bands, weights, or machines, and stretching. Speak with your primary care physician before beginning any physical activity.
Prescription Weight Loss Medications
Prescription weight loss medications may be considered a supplement to diet and exercise. Only a healthcare professional can prescribe these weight loss medications.
Comparison of Long-Term Effectiveness
The following chart compares the long-term effectiveness of three different obesity treatments.
|Treatment||Percent Who Maintain|
Weight Loss after 5 Years
|Diet & Exercise||2% to 5%|
|Bariatric Surgery||50% to 70%|
Bariatric surgery clearly has the best weight loss outcome compared to the other two treatments—50 to 70 percent of people were able to lose at least 50 percent of the excess weight and keep it off for five years.
After five years, only 2 to 5 percent of the people who dieted and exercised had maintained a weight loss of at least 10 percent.
People who had taken weight loss medications were not able to maintain any weight loss.
Results of Five-Year Follow-up
|TREATMENT||WEIGHT LOSS (% OF PATIENTS)|
|Diet and Exercise*||2% to 5%|
|Bariatric Surgery***||50% to 70%|
* Success measured as a loss of 10 percent of initial body weight.
** Weight loss is not maintained once treatment ends.
*** Success measured as a loss of 50 percent of excess body weight (equivalent to loss of approximately 20 to 25 percent of initial body weight).
The above chart compares the long-term effectiveness of three different obesity treatments: diet and exercise, weight loss medications, and bariatric surgery.
- Bariatric surgery clearly has the best weight loss outcome compared to the other two treatments—50 to 70 percent of people were able to lose at least 50 percent of the excess weight and keep it off for five years.
- After five years, only 2 to 5 percent of the people who dieted and exercised had maintained a weight loss of at least 10 percent.
- People who had taken weight loss medications were not able to maintain any weight loss.