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Being obese means having so much body fat that your health is in danger. Having too much body fat can lead to type 2 diabetes, heart disease, high blood pressure, arthritis, sleep apnea, and stroke.

Because of these risks, it is important to lose weight even if you do not feel bad now. It is hard to change eating habits and exercise habits. But you can do it if you make a plan.

To determine whether you are obese, you can use a measurement called a body mass index, or BMI, to decide whether your weight is dangerous to your health. The BMI is a combination of your height and weight. If you have a BMI of 30 or higher, your extra weight is putting your health in danger. If you are Asian, your health may be at risk with a BMI of 27.5 or higher. View BMI Chart [PDF]

Where you carry your body fat may be as important as how many extra pounds you have. People who carry too much fat around the middle, rather than around the hips, are more likely to have health problems. In women, a waist size of 35 in. (88 cm) or more raises the chance for disease. In men, a waist size of 40 in. (101 cm) or more raises the chance for disease. In Asian people, health problems are seen with a smaller waist size. In Asian women, a waist size of 32 in. (80 cm) or more raises the chance for disease. In Asian men, a waist size of 36 in. (90 cm) or more raises the chance for disease.



Obesity is a complex disease for which no single cause or cure exists. You gain weight when you take in more calories than you burn off. But obesity is influenced by many other factors, also: your family history, the type of work you do, your race, and your environment.

Overeating is easy in our culture today. Portions at fast-food and other restaurants are "super-sized" to the point that one meal can provide an entire day's worth of calories. Food is also a focal point of social activity. Gatherings of family and friends, work events, and holidays are usually centered around food. And eating can be a comfort when you are depressed or stressed.

Next, people are less active than ever. Some people hate to exercise and others may not have the time. Also, many of the conveniences we use, such as the remote control for the television, elevators, and cars, cut activity out of our lives.

Even making small changes—like walking your dog—can make a difference. Letting the dog out the door burns 2 calories. Walking the dog for 30 minutes burns 125 calories. Taking the car to a car wash uses 18 calories. Washing and waxing it yourself burns 300.

Other things can affect our weight, such as family history or genetics. If one of your parents is obese, you are 3 times as likely to be obese as someone with parents of healthy weight.

Your family's and friends' lifestyles can also affect your weight. If your family or friends eat a lot of high-fat or snack foods, eat at irregular times, and skip meals, you probably will too. And if they are not physically active, you may not be either.

Other things influence your weight and whether you are physically active, including:


Health Risks of Obesity

How obesity affects your health depends on many things, including your age, gender, where you carry your body fat, and how physically active you are. For example, if you are an older woman who gets regular physical activity, you may be at less risk for other weight-related health problems than a younger man who is not physically active.

If you are obese, you are more likely to develop type 2 diabetes, high blood pressure, high cholesterol and triglycerides, coronary artery disease (CAD), stroke, and sleep apnea, among other conditions. If you lose weight, your risk for these conditions is reduced.

Where you carry body fat is important. If fat builds up mostly around your stomach (sometimes called apple-shaped), you are at greater risk for type 2 diabetes, high blood pressure, high cholesterol, and coronary artery disease than people who are lean or people with fat around the hips (sometimes called pear-shaped).

Exams and Tests

Along with a regular medical checkup, you may have some tests to monitor your health.

Your doctor may want to do blood tests to check for type 2 diabetes, thyroid, or liver problems, and high cholesterol or high triglyceride levels.

Your doctor will check your blood pressure, ask about any medicines you are taking and discuss your medical history and your family's medical history. He or she will ask how active you are, whether you drink alcohol (and how much), your history of weight gain, and how often you have tried to lose weight.

Knowing your waist size along with your body mass index (BMI) can help your doctor check your risk for type 2 diabetes and coronary artery disease (CAD).


Treatment for obesity will be most successful if you create a long-term plan with your doctor. A reasonable goal might be to begin making lifestyle changes by increasing physical activity and limiting calories.

Your initial goal should be to improve your health, not to achieve an ideal weight. Although the “formula” for weight loss—to burn more calories than you take in—is not complicated, it is often hard to achieve and maintain. Along with lifestyle changes, medicines and surgery may be options for some people. The treatment you need depends on your level of obesity, your overall health, and your motivation to lose weight.

Health guidelines suggest that people should make lifestyle changes for at least 6 months before trying medicines or surgery. Your doctor may suggest medicines and surgery earlier if you also have conditions such as coronary artery disease or type 2 diabetes.

Medicines for obesity work in different ways. Depending on the medicine, they make you feel full sooner, limit your body's ability to absorb fat, or control binge eating. Surgery is used to reduce the size of the stomach and limit how many calories are absorbed by the intestines.

Your doctor may also suggest counseling. If you use food to cope with depression, loneliness, anxiety, or boredom, you need to learn new skills to deal with those feelings.

Ongoing treatment

See your doctor after 6 months to check your progress. Some people stop losing weight around this time, because their bodies adjust to fewer calories, and their motivation starts to slip.

At this point your doctor may want you to increase your activity and revisit the dietitian to make further changes in your diet. Your goals may switch from losing more weight to keeping the weight off. Staying active is very important for maintaining weight loss.

If you have lost weight but gained it back, don't be discouraged; it is not uncommon to try several times before weight comes off and stays off. Talk to your doctor about starting again. It may be helpful to work with others who are trying to lose weight in a structured program.

If you cannot keep weight off or have not managed to lose 1 lb (0.5 kg) per week, your doctor may want you to add medicines. Weight-loss drugs generally are used along with eating changes and exercise. Use of medicine without lifestyle changes is not likely to have long-term success. Medicines for weight loss include sibutramine, orlistat, and phentermine.


Treatment if the condition gets worse

If you do not lose weight, continue to gain weight, or have lost weight several times only to regain it, or if your doctor is concerned about a related health problem, you might need to try medicines or surgery.

Weight-loss medicines

Weight-loss medicines are not prescribed alone. Diet changes and physical activity are needed for keeping weight off long-term. If not, once medicine is stopped, weight will return.

Medicines for weight loss include sibutramine, orlistat, and phentermine. These drugs work by making you feel full sooner, lowering your appetite, or limiting the amount of fat your body can absorb.


Your doctor may suggest bariatric surgery if you have not been able to lose weight with other treatments and you are at high risk for developing other health problems because of your weight.

If your body mass index is over 40 or if it is 35 or higher and you have a serious medical problem that is made worse by your weight, one of the following surgeries may be an option:

This infomation was taken from the University of Michigan Health System's Health Library.