Maintaining a healthy body weight is essential for reducing the risk of heart disease, according to a new study from Denmark. This is true even for people who don’t have metabolic syndrome (MetS), a group of risk factors for heart disease, diabetes, and stroke.
“We documented that overweight and obese individuals have an increased risk of heart attack and disease even in the absence of metabolic syndrome,” says Dr. Børge Nordestgaard, co-author of the new study, published today in JAMA Internal Medicine. “In other words, even metabolically healthy overweight and obese people are at an increased risk of heart problems.”
While metabolic syndrome is sometimes viewed as a single condition, it includes several components—high blood pressure, increased fasting blood sugar levels, high triglyceride levels, low "good" HDL cholesterol levels, and a large waistline. A person must have at least three of these to be diagnosed with metabolic syndrome.
Results from previous studies were mixed, and some suggested that carrying extra weight is relatively harmless when metabolic syndrome is not also present—the so-called “healthy” overweight or obese.
The Danish researchers attempted to avoid the shortcomings of earlier studies. They examined a large population of more than 71,000 participants.
“Our study is the largest single-site study to date,” says Nordestgaard. “We solely recruited people from the general population, and we excluded all with heart attack and disease before study entry, thus eliminating reverse causation as a potential problem.”
Heart disease, which can make it difficult for people to exercise, can also lead to increased body weight. Excluding these people at the start of the study allowed researchers to focus on the negative effects of an unhealthy weight.