If you must choose between fat, then, between margarine and butter, you should prefer the second.

It is certainly a source of saturated fats that should be consumed in small quantities, because they damage the cardiovascular system. On the other hand, margarine is the source of the so-called trans fatty acids, produced during the process of hydrogenation of vegetable oils.

The trans fats are believed to increase the "bad" cholesterol and decrease "good" - which means that is equally, if not more, harmful to the cardiovascular system than saturated fat (there in market certain types of margarine with removed trans fats).

Finally, if in doubt, between olive oil or vegetable oil, then the specific rule say that olive oil is preferable because it is rich in monounsaturated fatty acids, which act beneficially on the cardiovascular system. It is also a source of vitamin E, which has antioxidant (anti-aging and anticancer) activity.

The seed oil is always refined, ie treated in the aroma, color and taste. It is also a source of polyunsaturated fatty acids, which is already included in olive oil.