Trans Fat On Food

A type of trans fat occurs naturally in the milk and body fat of ruminants (such as cattle ans sheep) at a level of 2-5% of total fat. Natural trans fat, which include conjugated linoleic acid and vaccenic acid, originate in the rumen of these animals.

Animal-based fat were once the only trans fats consumed, but by far the largest amount of trans fat consumed today is created by the processed food industry as a side-effect of partially hydrogenating unsaturated plant fats. These partially hydrogenated fats have displaced natural solid fats and liquid oils in many areas, notably in the fast food, snack food, fried food and baked good industries.

Partially hydrogenated oils have been used in food for many reasons. Partial hydrogenation increases product shelf and decreases refrigeration requirements. Because baking often requires semi-solid fats to suspend solids at room temperature, partially hydrogenated oils can replace the animal fats traditionally used by bakers. They are also inexpensive alternative to other semi-solid oils such as balm oil.

Food containing artificial trans fat formed by partially hydrogenating plant fats may contain up to 45% trans fat compared to their total fat. Baking shortenings generally contain 30% trans fat compare to their total fats, while animals fats from ruminants such as butter contain to 4%. Those margarines not reformulated to reduce trans fats may contain up to 15% trans fat by weight.

It has been establish that trans fat in human milk fluctuate with maternal consumption of trans fat, and the amount of trans fats in the bloodstream of breastfed infants fluctuates with the amounts found in their milk.