Originally given the mysterious name Syndrome X, metabolic syndrome was first described more than 30 years ago. It is a cluster of related cardiovascular risk factors that includes excessive abdominal fat, high blood pressure and elevated blood sugar. According to its proponents, about one-third of American adults have metabolic syndrome.
While it’s clear that the individual components of metabolic syndrome increase the risk of heart disease, strokes and/or type 2 diabetes, there are questions about whether, in combination, they form a distinct syndrome. And if they do, does the concept help in the diagnosis or treatment of people who have it? Some researchers no longer think so.
The key elements
Definitions vary, but according to a common one, you have metabolic syndrome if you develop three or more of the following:
• Obesity, especially in the abdomen: a waist circumference of more than 40 inches for a man, 35 inches for a woman.
• Low HDL (“good” cholesterol): below 40 for a man, below 45 for a woman.
• High triglycerides (fats in the blood): 150 or above on a fasting test.
• Elevated blood pressure: 130/85 or above.
• Elevated blood sugar: 100 or more on a fasting blood glucose test. Blood sugar greater than 125 indicates diabetes, while levels between 100 and 125 indicate increased risk for developing diabetes.
A fuzzy picture
One of the first papers to raise questions about the concept of metabolic syndrome was a 2005 joint statement from the American Diabetes Association and the European Association for the Study of Diabetes.
An essential problem, it found, is the lack of agreement on the general definition of the syndrome and about its specific components and their cut-off points. For example, some organizations determine obesity by focusing on waist circumference, while others use body mass index. Some include inflammation in the body (determined by elevated levels of C-reactive protein) as a factor, though most do not.
Perhaps the biggest problem with the concept is that there’s no clear evidence that metabolic syndrome confers a greater risk than the sum of the individual risk factors—which is what the term “syndrome” suggests. A 2010 paper in the Archives of Internal Medicine, for instance, reviewed seven clinical trials that monitored plaque progression in more than 3,500 people, nearly 60 percent with metabolic syndrome. When the researchers adjusted for the individual factors in predicting risk, “metabolic syndrome no longer offered any advantages as an independent predictor.”
Thus, we think it may be time to give “metabolic syndrome” an early retirement.
Treat the components, forget the syndrome
In practical terms, it may not matter whether metabolic syndrome is a distinct condition or not. There’s no magic pill for it. If your doctor says you have it, you simply have to treat the individual risk factors. Here are the key steps:
• Lose weight if you’re overweight. It’s essential to reduce your calorie intake and/or burn more calories via physical activity. Losing just 10 to 20 pounds can restore insulin sensitivity and help control blood sugar and blood pressure.
• Choose healthy carbohydrates. Cut down on sugary foods and refined-grain products such as white bread and starchy snack foods. Instead, eat more high-fiber foods—that is, vegetables, beans, whole grains and fruits.
Fiber slows the digestion of the carbohydrates, so there’s less effect on insulin and blood sugar. Limit sodas and other sugary drinks; a recent study in Diabetes Care linked them to the components of metabolic syndrome.
• Cut down on sodium. That will lower blood pressure in sodium-sensitive people.
• Limit alcohol if your triglyceride level is high, or avoid it altogether. Though it can modestly raise HDL (“good”) cholesterol, alcohol can boost triglycerides.
• Exercising regularly can’t be overemphasized. Even when it doesn’t produce weight loss, it can increase insulin sensitivity and have cardiovascular benefits.