Obesity is a heart attack risk factor can be controlled—or, even better, avoided or eliminated altogether.

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Obesity

Every year, more and more Americans are classified as overweight or obese. According to the latest statistics, about 67 percent of adult Americans are overweight, including about 34 percent who are obese. Overweight or obese men and women have an increased risk of heart attacks and a greater likelihood of developing risk factors.

Body Mass Index (BMI)

Guidelines issued jointly by the National Heart, Lung, and Blood Institute and the National Institute of Diabetes and Digestive and Kidney Diseases recommend using body mass index (BMI)—a measurement of body weight in relation to height—to determine whether you are overweight or obese.

BMI is calculated by multiplying your weight in pounds by 703, then dividing the result by the square of your height in inches. For example, if you weigh 190 lbs and are 5 feet 10 inches tall, multiply 190 × 703 (which equals 133,570). Then divide this number by 70 inches squared, or 4,900 (133,570 ÷ 4,900 = 27.3). The result: Your BMI is 27.3. You can also use the online BMI calculator at www.nhlbisupport.com/bmi.

Overweight is defined as a BMI of 25 to 29.9; obesity, as a BMI of 30 and over. As BMI rises, blood pressure and triglyceride levels rise and HDL cholesterol levels drop. These adverse changes in blood pressure and lipid levels increase your risk of a heart attack. In addition, an analysis of 21 studies found that a BMI greater than 25 is a risk factor for a heart attack, independent of blood pressure and cholesterol levels.

Waist Circumference

How excess weight is distributed on your body is also important in determining heart attack risk. Research now shows that extra weight around your middle (called abdominal obesity) is particularly dangerous for your heart because it causes insulin resistance (the reduced ability to respond to insulin, a hormone that regulates blood glucose levels). Insulin resistance can lead to diabetes, high triglyceride and low HDL cholesterol levels, hypertension, and an increased risk of a heart attack.

One way to detect abdominal obesity is to measure your waist circumference. A waist circumference of greater than 40 inches in men or greater than 35 inches in women indicates abdominal obesity.

Physical Inactivity

Physical inactivity is an important risk factor for a heart attack. The American Heart Association recommends at least 30 minutes of moderate-intensity exercise (for example, brisk walking) five days a week. Exercise not only reduces your risk of a heart attack but also helps to control body weight, lower blood pressure, reduce the risk of diabetes, and improve triglyceride levels.

Publication Review By: Roger S. Blumenthal, M.D. and Simeon Margolis, M.D., Ph.D.

Published: 08 Mar 2011

Last Modified: 15 Jan 2015