If you swap out a little bit of the healthy fats in your Mediterranean diet (like olive oil) for walnuts, your bad cholesterol (LDL) and overall cholesterol go down a bit—which might help your heart.

Eating walnuts instead of other healthy fats like olive oil may lower a dangerous blood fat called lipoprotein(a) in men with high cholesterol—but it doesn’t seem to help women the same way.

Eating walnuts can make the 'bad' cholesterol in your blood healthier by filling it with good fats, without making it more likely to cause damage—like adding armor instead of fuel to a fire.