Obesity | Symptoms & Causes | Diagnosis
 


What this section contains?
1. What is Obesity?
2. Cause
3. Diagnosis & Tests
4. Prevention & Risk Factors
5. Treatments & Therapies
Obesity

What is Obesity?

Obesity: The state of being well above one's normal weight.A person has traditionally been considered to be obese if they are more than 20 percent over their ideal weight. That ideal weight must take into account the person's height, age, sex, and build.Obesity has been more precisely defined by the National Institutes of Health (the NIH) as a BMI of 30 and above. (A BMI of 30 is about 30 pounds overweight.)

Cause

At an individual level, a combination of excessive food energy intake and a lack of physical activity is thought to explain most cases of obesity. A limited number of cases are due primarily to genetics, medical reasons, or psychiatric illness. In contrast, increasing rates of obesity at a societal level are felt to be due to an easily accessible and palatable diet, increased reliance on cars, and mechanized manufacturing.

A 2006 review identified ten other possible contributors to the recent increase of obesity: (1) insufficient sleep, (2) endocrine disruptors (environmental pollutants that interfere with lipid metabolism), (3) decreased variability in ambient temperature, (4) decreased rates of smoking, because smoking suppresses appetite, (5) increased use of medications that can cause weight gain (e.g., atypical antipsychotics), (6) proportional increases in ethnic and age groups that tend to be heavier, (7) pregnancy at a later age (which may cause susceptibility to obesity in children), (8) epigenetic risk factors passed on generationally, (9) natural selection for higher BMI, and (10) assortative mating leading to increased concentration of obesity risk factors (this would increase the number of obese people by increasing population variance in weight).

Diagnosis & Tests

To diagnose obesity, your doctor will typically perform a physical exam and recommend some tests.

These exams and tests generally include:

  • Taking your health history.Your doctor may review your weight history, weight-loss efforts, physical activity and exercise habits, eating patterns and appetite control, what other conditions you've had, medications, stress levels, and other issues about your health. Your doctor may also review your family's health history to see if you may be predisposed to certain conditions.
  • A general physical exam. This includes measuring your height; checking vital signs, such as heart rate, blood pressure and temperature; listening to your heart and lungs; and examining your abdomen.
  • Calculating your BMI. Your doctor will check your body mass index (BMI). A BMI of 30 or higher is considered obesity. Numbers higher than 30 increase your health risks even more. Your BMI should be checked at least once a year because it can help determine your overall health risks and what treatments may be appropriate.
  • Measuring your waist circumference. Fat stored around your waist, sometimes called visceral fat or abdominal fat, may further increase your risk of heart disease and diabetes. Women with a waist measurement (circumference) of more than 35 inches (89 centimeters, or cm) and men with a waist measurement of more than 40 inches (102 cm) may have more health risks than do people with smaller waist measurements. Like the BMI measurement, your waist circumference should be checked at least once a year.
  • Checking for other health problems. If you have known health problems, your doctor will evaluate them. Your doctor will also check for other possible health problems, such as high blood pressure and diabetes. Your doctor may also recommend certain heart tests, such as an electrocardiogram.
  • Blood tests. What tests you have depend on your health, risk factors and any current symptoms you may be having. Blood tests may include a cholesterol test, liver function tests, a fasting glucose, a thyroid test and others.


Gathering all this information helps you and your doctor determine how much weight you need to lose and what health conditions or risks you already have. And this will guide treatment decisions.

Prevention & Risk Factors

Obesity is mostly preventable through a combination of social changes and personal choices. Changes to diet and exercising are the main treatments. Diet quality can be improved by reducing the consumption of energy-dense foods, such as those high in fat or sugars, and by increasing the intake of dietary fiber. Medications can be used, along with a suitable diet, to reduce appetite or decrease fat absorption. If diet, exercise, and medication are not effective, a gastric balloon or surgery may be performed to reduce stomach volume or length of the intestines, leading to feeling full earlier or a reduced ability to absorb nutrients from food.

Treatments & Therapies

The goal of obesity treatment is to reach and stay at a healthy weight. This improves your overall health and lowers your risk of developing complications related to obesity. You may need to work with a team of health professionals