Fats form an important macro-nutrient in our diet producing bulk, taste, ease absorption of fat soluble vitamins, like A,D,E,K, provide energy as a backup when there is insufficient carbs, and for cushioning vital organs, among more things. In spite of such important functions, fats were demonised by the medical profession, and big cat drug manufacturers in US, all because Ansell Key an American scientist published a study about different countries that made it look that heart disease was associated with fat intake. Fat is used to build new cells and is critical for normal brain development and nerve function

We all know that too much saturated fat in our diet can result in high cholesterol levels in blood, cause inflammation, and participate in plaque pathogenesis, resulting in  blockage of arteries.

The medical profession then acclaimed unsaturated fats, because they never clogged up arteries, being liquid at normal temperatures, and were heart friendly.  Taking too much of fat, both saturated or unsaturated, caused problems in the body, including obesity. The unsaturated fats were classified as mono-unsaturated fatty acids and polyunsaturated fatty acids.

The food industries then manipulated the unsaturated fats to look like butter in consistency and spread, by running through many stages to thicken the oil by a process called hydrogenation (pumping hydrogen vapour into the fatty acids). This process resulted in mimicking saturated fats by changing its chemical structure Margarines are the best examples of popular trans fat foods people having been consuming for a long time.
So, saturated fats were bad, and Trans fats became good as they were manufactured from unsaturated fats.

Trans fat behaves like a saturated fat because of its chemical structure. With time it was clear that trans fats increased the risk of heart disease by raising bad cholesterol (LDL), while lowering the good cholesterol (HDL), in our blood.

Such hydrogenated fats are found in many of the foods as saturated fats and they include

• Baked goods (cookies, cakes, pies, and crackers)
• Ready-to-use frostings
• Snack food (such as potato chips and microwave popcorn)
• Fried food typically found in fast food restaurants (such as French fries, fried chicken, and doughnuts)
• Refrigerated dough products (such as biscuits, cinnamon rolls, and frozen pizza)
• Vegetable shortening
• Ice cream and chocolate
• Stick margarine
• Coffee creamer

(Naturally occurring trans fats are found in small amounts in dairy products, beef, veil, lamb and mutton)

The body cells cannot differentiate between natural saturated fats and the artificial trans-fat. Saturated fats including cholesterol form with some protein and carbohydrates part of the structure of every cell membrane. The fats found in the form of oil are continually renewed and replaced. Trans fats are absorbed in to your cell membrane where healthy essential fats should be integrated. The trans fats seem to irreversibly disrupt cell membrane function and communications with other cells and cause all the body havoc.

These transfat in food are listed as “shortening”, partially hydrogenated vegetable oils or hydrogenated vegetable oils.

Foods containing any of the above trans fats should be avoided. These hydrogenated fats are labelled as “cholesterol free” and that is how they advertise, and one should not get deceived.

One advantage in using trans fats is that the shelf life of the item could be prolonged and further give stability to the foods.

By looking at the label you could find out whether any form of trans fat is listed among the ingredients. According to FDA regulations if less than 0.5 grams of trans fat is added, when declared, shall be expressed as zero. Consuming such foods containing less than 0.5 grams of trans fat with about four servings, you have reached a fair limit, though the label says zero transfats per serving.

In Canada the definition is that the food contains less than 0.2 grams of transfat, the content may expressed as zero, a much heathier proposition.
The FDA has ultimately realised the ill-health, trans fats are causing, and decided to ban the use of partially hydrogenated oils, which seems to be the main source of clogging of arteries. This action will save many thousands of lives and Mayne wrote on the FDA Voice blog, ”It has become clear that what’s good for extending shelf life is not equally good for extending human life.”

Food makers are given 3 years to remove partially hydrogenated oils from products by an order given by the FDA.

Food makers have already found substitutes for these controversial fats and there is no need to add them in the future.

Experts can’t say there’s any safe level of trans fats to eat, "because we don't have the evidence," says Walter Willett, MD, DrPH, MPH, professor of epidemiology and NUTRITION at the Harvard T.H. Chan School of Public Health.

Robert Collete, president of the Institute of Shortening and Edible Oils, has agreed to do what they have done for the past 10 years and work with the food industry in formulating other alternatives.

Cooking oils
Trans fat is found in the canola oil (rape seed oil) you purchase at the supermarket. Trans fat occurs during the processing at high temperatures. The raw seed begins with high levels of omega-3 oils: these tend to be oxidised during processing producing rancid odours. During the process of deodorising some omega-3 fatty acids are converted to trans.

If a label says “vegetable oil” it is likely to be made from canola. (ref: www.tfx.org.uk)

You make your own trans fat
When you fry lot of your food in a frying pan with ordinary vegetable oil, you inevitably make trans fat at high temperatures. This means the tasty ‘wadai’ fried in vegetable oil could be impregnated with trans fat.