New research into cholesterol and the cholesterol-lowering medications called statins is leading doctors to reconsider how much LDL cholesterol (the so-called "bad cholesterol") is too much.

Studies already have proven that statins such as atorvastatin (Lipitor), pravastatin (Pravachol), simvastatin (Zocor), lovastatin (Mevacor), fluvastatin (Lescol), and rosuvastatin (Crestor) are quite effective in lowering LDL cholesterol levels and reducing cardiovascular disease risk. These medications work by blocking the production of low-density lipoproteins, which lead to the plaque buildup that raises a person's risk of heart attack and stroke. But new research by the Cleveland Clinic suggests that the recommended healthy target level for LDL (100) may not be low enough, especially for people with other risk factors for heart disease.

The study found that, in one group of heart disease patients, any new buildup of plaque in the arteries stopped when LDL cholesterol levels were lowered to around 80. Patients achieved this by taking the highest dose of Lipitor. In the second group of patients, who took a lower dose of the statin Pravachol, LDL levels hovered around 110 and the plaque buildup actually worsened. This is significant because, according to current guidelines, a level of 110 is not necessarily considered "high."

"There is just a tremendous amount of data showing that statins reduce cardiovascular risk by as much as one-third with just five years of use," says Daniel Rader, MD, director of the preventive cardiology and lipid clinic at the University of Pennsylvania. "The question now for people with heart disease, diabetes, or very high risk factors is whether the target LDL level should be even lower than 100. Some doctors are already starting to target as low as 80 for these individuals."