What are overweight and obesity?
Overweight and obesity are conditions in which a person is carrying too much extra body fat. The two terms do not mean exactly the same thing: obesity is a more severe form of being overweight.
Excess body fat puts you at risk for blood clots in the veins of the legs (DVT) that can travel to the lungs and cause a potentially deadly pulmonary embolism. Women who are overweight or obese are also more likely to develop diabetes, which may make the blood more likely to clot. Excess weight also puts you at risk for many other diseases including PAD, heart disease, stroke, and heart failure. On average, a woman who is overweight will die 3 years earlier than if she had a healthy weight, and an obese woman will die more than 7 years earlier.
More than two-thirds of American women are overweight or obese. The burden of excess weight affects certain races more than others: obesity is most common in African American women, followed by Hispanic and white women, with a lower rate in Asians. It is also a growing problem among children.
What causes overweight and obesity?
The main causes of being overweight or obese are eating too many calories and not being physically active enough. If you eat more calories than your body burns up, the extra calories are stored as fat. Other factors that may affect your weight include your genes (obesity tends to run in families), your metabolism (how your body processes food), and your age (your metabolism slows down as you get older). Sometimes an illness or medications (such as those used to treat mood disorders, seizures, migraines, high blood pressure, and diabetes) can contribute to weight gain. However, calories in (from food and drink) and calories out (burned during exercise) remain the keys to weight control.
How is obesity measured?
Because your ideal weight is related to how tall you are, the most commonly used way to evaluate your body weight and determine your ideal weight is called the Body Mass Index, or BMI. Your BMI is calculated by taking your weight in kilograms and dividing it by your height in meters squared. A woman with a BMI between 25 and 29 is considered overweight, and a woman with a BMI of 30 or more is considered obese.
|Underweight||Less than 18.5|
|Normal||18.5 to 24.9|
|Overweight||25 to 29.9|
|Obese||30 or higher|
Although the BMI is the most widely used tool to measure the health effects of weight, it does have limitations. For some people, the BMI may not be an accurate gauge of health risk. For example, BMI can overestimate body fat in women who have an athletic, muscular build, and underestimate body fat in women who have lost muscle mass or in older women. Some races also have different natural amounts of body fat, and BMI may not be as accurate in Asians, Arabs, and mixed-race Africans.
Does obesity increase my risk of vein disease?
Obese women are 2 to 3 times more likely than healthy-weight women to develop blood clots in the deep veins of the leg (DVT), which can travel to the lungs and cause a potentially deadly pulmonary embolism. A large Danish study of 57,054 patients (52% were women) found that obese women had nearly 3 times the risk of suffering a DVT or PE compared with women who were a healthy weight. Another study found that for every 4-point increase in BMI, a woman’s risk of DVT or PE went up by 26%, even after other blood clot risk factors were taken into account.
Obesity also makes you more likely to develop chronic vein disease, a condition in which the veins become unable to pump enough blood back to the heart, causing blood to pool in the legs. This type of vein disease is common in obese women, who have more blood to move through the body and often have reduced physical activity. Overweight and obese patients are also at increased risk for problems caused by vein disease, like skin changes and ulcers on the legs. In one study of 272 patients (64% were women) with chronic vein disease, the more excess weight a person carried, the more severe their disease.
Will losing weight reduce my risk of vein disease?
No studies have specifically tested whether losing weight can lower a woman’s long-term risk of vein disease or its complications, but the health risks of extra weight are well established. Because obesity dramatically increases your risk of vein disease, including DVT, pulmonary embolism, and chronic vein disease, achieving and maintaining a healthy weight is critical to protect the health of your veins.
All women should achieve and maintain a healthy weight (a BMI between 18.5 and 24.9) to prevent heart and blood vessel disease. Even losing as little as 10% of your body weight can reduce your risk of developing diabetes and help control your blood sugar if you already have diabetes.
How can I lose weight?
To learn about your options for losing weight and reducing the health risks that go along with excess weight, see our Weight Loss Guide.