Death and heart disease risks increased with trans fats, not saturated fats

Researchers conducting a systematic review of currently available observational studies have concluded that, while trans fats are associated with a greater risk of death and coronary heart disease, saturated fats are not.

Trans fats are formed when hydrogen is added to vegetable oil and can be found in fast food, frozen pizza, margarine and packaged baked goods among other foods.

In fact, saturated fats were not associated with an increased risk of death, heart disease, stroke or type 2 diabetes. The results of the systematic review are published in The BMJ.
Saturated fats typically come from animal products such as meat, egg yolks, butter, milk and salmon, contributing about 10% of energy to the North American diet.
In contrast, trans fats are produced industrially from plant oils and found in margarine, packaged baked goods and snack foods. They contribute 1-2% of energy to the North American diet.
At present, dietary guidelines recommend limiting saturated fat consumption to less than 10% of daily energy intake to reduce the risk of ischemic heart disease and stroke. Guidelines also recommend that trans fat consumption should be less than 1% of energy.
However, several studies have challenged the assertion that the intake of saturated fats is associated with cardiovascular risk.source