With the recent advocacy to eliminate Trans Fatty Acids (TFAs) from the food supply system in Nigeria, a critical question in the minds of many is what exactly are the sources of trans fatty acids?
Dietary fats are the most concentrated form of food energy. Fats that are liquid at room temperature are called oils, while fats that are firm at room temperature are called solids. We have two types of dietary fats: saturated and unsaturated.
The difference between the two depends on the amount of hydrogen atoms that surround the fatty acid structure, called “saturation.” Saturated fatty acids are “saturated” with hydrogen atoms and are typically solid, while unsaturated fatty acids are not “saturated” with them and are typically liquid.
TFAs are unsaturated fatty acids that come from either natural or industrial sources. Naturally-occurring trans fat come from ruminants (cows and sheep). Industrially-produced trans fat are formed in an industrial process that adds hydrogen to vegetable oil, converting the liquid into a solid, and resulting in “partially hydrogenated” oil (PHO).”
Hydrogenation is a chemical process that adds hydrogen to the unsaturated bonds. In this way, an unsaturated fat can be turned into a saturated fat and increase its melting point . For edible purposes and for commercial use, we produce solid fats, (such as Margarines) which contains hydrogenated (hardened) oils as their major ingredients. This is because of successfully converting low-melting unsaturated fatty acids and glycerides to higher-melting saturated products.”
Partially hydrogenated oils are made when hydrogen is added to vegetable oil (hydrogenation process) to increase shelf-life and flavour stability of foods. Partial hydrogenation results in the addition of hydrogen atoms at some of the empty positions, with a corresponding reduction in the number of double bonds.
Typical commercial hydrogenation is partial to obtain a malleable mixture of fats that is solid at room temperature, but melts during baking, or consumption. In a nutshell, it makes it edible.
Sources of trans fatty acids come from partially hydrogenated vegetable oils which are found in margarine’s, shortenings, cakes, pies, and cookies (especially with frosting), candies (especially with creamy fillings), crackers, snack foods, microwave popcorn (buttered and flavoured varieties), frozen pizzas, frozen biscuits, pastries, muffins, doughnuts (especially frosted or cream-filled), breaded and fried chicken and fish, fried fast foods. Also, the practice of recycling oils for frying leads to TFAs.
However, there are alternatives to the use of partially hydrogenated vegetable fats in diets. One of the healthiest alternatives to using saturated or partially hydrogenated fats is the use of natural unsaturated liquid vegetable oils such as olive, canola, corn, or soy oils. They contain high levels of monounsaturated Fats.
They are not subjected to the harmful processing steps seen in TFAs. Olive oil, especially extra virgin, is among the least processed cooking oils on the shelves which makes it retain most of its antioxidants, vitamins, and minerals.
It is pertinent to state that the responsible public health response to the consumption of trans fatty acids, is “public health awareness on the adverse effects of trans fatty acids. The use of food labels whereby consumers have a choice to read labels and decide if they want to use a product is a good step as well.
I support governments and regulating agencies efforts at reducing the consumption of trans fat. Rigorous public health awareness programmes at Primary, Secondary and Tertiary health centres should be encouraged.
While individuals should be cautious and avoid to the barest minimum the consumption of TFAs in their diets, it is established that such TFAs have health hazards. The use of alternatives as elaborated in this piece is advisable just like maintaining good cooking habits is.
Family Physician and President Medical Initiative For Africa, Dr Taiwo Fasoranti