so what is a trans fat really? a trans fat is a liquid fat that is turned into a solid. although there is a very small amount of natural trans fats in meat and dairy products,most of them are created by adding hydrogen to liquid fat. food-makers do this because it makes the product last longer on the shelf. have you ever wonderd why cookies can still be crispy and "tasty" after six months to a year on a store shelf? it is because of trans of trans fats. trans fats are typically found in things like donuts, french fries, cookies, microwave popcorn, and potato chips.