If you swap out butter and fatty meats for oils and nuts, your 'bad' cholesterol goes down, which helps prevent clogged arteries and heart problems.

If swapping butter for olive oil doesn’t lower your ‘bad’ cholesterol much, then maybe this common diet advice won’t help you either.

Not all saturated fats are the same—some kinds, like those in dairy or coconut oil, might actually help your good cholesterol go up and bad cholesterol go down, while others, like those in red meat, might make your bad cholesterol worse.

If you swap out butter and fatty meats for bread, pasta, or olive oil, your blood might show higher levels of a type of fat particle called lipoprotein(a), which could be a concern for heart health — carbs raise it more than olive oil.

If you swap out butter and fatty meats for oils like sunflower or soybean oil, you might lower your risk of heart disease by about 30%—just like taking a statin pill—because it helps reduce the 'bad' cholesterol that clogs your arteries.

Switching from foods high in saturated fat (like butter) to foods full of sugar and white bread doesn’t make your heart any safer — studies show it doesn’t help prevent heart disease.