From this BBC article 'Good fat' cuts heart risk by a fifth, study shows:
Experts said cutting down on saturated fats, found in butter and meat, was just one part of a healthy diet. It is recommended that adults get no more than 11% of their energy from saturated fats. This is because the fats raise the levels of bad cholesterol that block the arteries to the heart. In comparison, polyunsaturated fats have the opposite effect by increasing the levels of good cholesterol.