Trans Fatty Acid: a health risk
Trans Fatty Acids (TFAs) tend to raise total blood cholesterol levels. In fact, some scientists believe that they raise cholesterol levels more than the saturated fats.
Remember, many fast foods contain high levels of TFA.
Fats or simply the oils that we use for cooking or making commercially-prepared foods (cookies, cakes, doughnuts, pies, etc.) are either saturated or unsaturated. Animal fats are a primary source of saturated fats. Certain plant oils are also sources of saturated fats, namely, the palm oil and the coconut oil.
Unsaturated fatty acids can be of one of the two types: cis and trans. The cis form is more common than the trans form. And it is the trans form that is harmful.
TFAs tend to raise LDL (bad) cholesterol and lower HDL (good) cholesterol when used instead of cis or natural oils.
The challenge is to keep the intake of trans fat to less than 1 percent of total calories. For example, if you need 2000 calories per day, make sure you consume less than 2 grams of trans fat.
How does one estimate the TFA content of foods? Because there are no standard methods, it is difficult to estimate TFA content in food items. It is also difficult to estimate intake, especially the long-term intake. Margaraine, animals products (beef, pork, lamb), cookies (biscuits) and white bread are major sources of TFAs.
Even though there is labeling to be done on food items by law, lots of foods that we take, especially the fast foods escpae it. There is no labeling regluation for fast food, and it can be advertised as cholesterol-free and cooked in vegetable oil.
Eating one doughnut (3.2 gram of TFA) and a large order of french fries (6.8 gram of TFA) add up to 10 grams of TFA; hence lack of regulation for restaurants to label foods they make can be harmful to health.
Some technical stuff: During food processing, margarine and shortening are fats that undergo a chemical process called Hydogenation (Hydrogenate means to add hydrogen atom. When unsaturated fatty acids are hydrogenated, some of the hydrogen atoms are added on opposite side of the molecule to the already attached hydrogen. The cis form convert to trans, and the fatty acid becomes saturated.
Dr. Ajay Sati
