Here's what the researchers found: Both bad (LDL) and good (HDL) cholesterol levels are lowered by margarine. But softer spreads most reduce bad cholesterol (LDL) and least reduce good cholesterol; conversely, stick margarine least reduces bad cholesterol and most reduces good cholesterol. Butter ends up somewhere in the middle. If the results sound confusing, it's because they are. "Margarine apparently has some benefits," says TIME senior science writer Jeffrey Kluger, "but not as much as we once believed."
Soft margarine is better for you than butter, but butter is better for you than hard margarine. That appears to be the conclusion of the latest study centered on the great margarine-vs.-butter controversy. Research published in Thursday’s issue of the New England Journal of Medicine indicate that the softer the margarine spread, the lower amount of LDL, or so-called "bad" cholesterol. On the other hand, the production process that results in harder margarines, called hydrogenation, introduces more trans fatty acids, which scientists believe results in a signficant reduction in HDL, so-called "good" cholesterol.