Trans fat is found naturally in small amounts; however, when oils are processed (hydrogenated), it leads to increased quantity of trans fats.

Trans fat is a geometric configuration of the fat molecule; two carbon chain branches are on the opposite sides (trans) of a double bond in the molecule. It can also occur at very low levels in some meat and dairy products.

Trans fat can occur naturally at very low levels in some meat and dairy products. Artificial trans fat is made when oil undergoes hydrogenation, in which hydrogen is added to liquid oil to make it more solid.

There are many products, in which partially hydrogenated oils (PHOs) are used; these include bakery products like biscuits, cakes, pizzas, pastries and fried products like potato, corn chips and also deep fried foods like French fries, doughnuts, fried chicken and various coffee creamer, Indian deep fried snacks, margarine etc.

A lot of trans fat is consumed in India in the form of vanaspati, which is a cheaper source of fat that also helps improve taste. Vanaspati is used for cooking many Indian food items such as paranthas, bhaturas, puris and tikkis. If the same oil is used again, it can lead to increased problem.

According to a research, trans fat consumption leads to increased bad cholesterol (LDL) in blood and decreases the amount of good cholesterol (HDL). It increases the risk of heart attacks and coronary heart disease. Trans fats also contribute to development of hyper tension, Type 2 diabetes, and obesity.