Low Cholesterol? Don't Brag Quite Yet

New York Times: "Not all that long ago, a low cholesterol score was seen as a sign of relative good health and a low risk of heart disease. But increasingly, doctors are identifying a group of people whose levels of L.D.L, the so-called bad cholesterol, are low, but who still appear to be at increased risk for atherosclerosis, heart attack and stroke.

They have a condition known as metabolic syndrome, a cluster of risk factors that include mild hypertension, elevated glucose levels, high triglycerides and low levels of H.D.L. cholesterol.

People with the syndrome also tend to have high levels of a protein, known as C-reactive protein, or CRP, which is released during inflammation and has recently been linked to heart disease.

The report advised that the syndrome should be diagnosed in people who had three of five risk factors: a large waist, high triglycerides, low H.D.L., somewhat elevated blood pressure and elevated fasting glucose.

But not everyone agrees. Some endocrinologists, including Dr. Reaven, worry that the diagnostic criteria exclude insulin-resistant people, whose cells are less sensitive to insulin, but who may not be overweight or have as many as three risk factors.

East Indians, for example, have a high rate of insulin resistance, though they tend to be thin. And people who are insulin-resistant, endocrinologists say, are also at high risk for heart disease and diabetes, as well as other illnesses like fatty liver disease (the leading cause of cirrhosis and end-stage liver disease), polycystic ovary syndrome and sleep-disordered breathing.

Many endocrinologists prefer a different name for the condition: insulin resistance syndrome.

The American Association of Clinical Endocrinologists has recommended that doctors widen the net by considering other factors, including body mass index; a more sensitive test of insulin resistance; age, exercise habits and ethnic background; and family history of Type 2 diabetes, hypertension and cardiovascular disease.

Some experts believe doctors should also look carefully for high levels of C-reactive protein because of its role in inflammation.

Some experts are also looking at another possible risk factor to add to the syndrome: fibrinogen, a protein that signals the body to form or break down blood clots.

Whatever the cause, the research clearly shows that losing weight reduces all components of metabolic syndrome. Triglycerides go down, blood glucose goes down, H.D.L. goes up, hypertension goes down, the waist narrows and CRP levels drop.

Recent studies of various weight-loss programs - following a Mediterranean-style diet; taking Xenical, a prescription weight-loss drug; or undergoing surgical treatment - have found that all these routes are effective in reducing the risk factors of metabolic syndrome and even in curing some people of the syndrome.

A 2004 study in The Journal of the American Medical Association compared people who were put on a Mediterranean diet - whole grains, fruits and vegetables, nuts and olive oil - with a group that ate a prudent but nonspecific diet. Members of each group also increased their exercise by 60 percent.

After two years, 60 of 90 patients on the Mediterranean diet no longer had metabolic syndrome, as against 12 of 90 in the comparison group, the researchers found. Those on the Mediterranean diet also lost more than double the weight.

Meanwhile, experts at the Cholesterol Education Program are trying to educate doctors and patients about the syndrome, especially groups that appear to be at higher risk for it, like Hispanics, African-American women, East Indians and the obese."