Overview of the dangers of trans fatty acids

The food with the most trans fatty acid content is foreign fast food...

"I am now in Beijing and see many children who are obese because of eating foreign fast food. I want to cry because I have no ability to help them!"

--A speech delivered by Zhao Lin, a health education expert, vice chairman of the Trace Elements Branch of the Chinese Society of Traditional Chinese Medicine, and deputy director of the Nutrition Department of the General Hospital of the People's Liberation Army, while participating in the recording of CCTV's "People's New Weekly" column.

Trans fatty acid is a type of unsaturated fatty acid. It is the general term for all unsaturated fatty acids containing a trans double bond. It is named because the hydrogen atoms connected to the double bond are distributed on both sides of the carbon chain. Although trans fatty acids are also unsaturated fatty acids, the existence of trans double bonds has greatly changed the spatial configuration of fatty acids. The fatty acid molecules have a rigid structure and are close to saturated fatty acids. The content of trans fatty acids in different hydrogenated oils can fluctuate greatly due to different processing processes, generally accounting for about 10% of the oil content, and can reach up to 60%.

Trans fatty acids in life come from the following aspects: First, trans fatty acids produced during the hydrogenation of oils, the so-called "artificial oil", which is the main source of trans fatty acids; meat from ruminants and dairy products are The main source of natural trans fatty acids in the diet; trans fatty acids can also be produced by the refining and cooking process of oils. For example, during the refining process of vegetable oil such as decoloring and deodorization, polyunsaturated fatty acids undergo thermal polymerization, causing isomerization of fatty acids and producing some trans fatty acids. Studies have shown that the trans fatty acid content in oils deodorized at high temperatures can increase by 1% to 4%; in addition, in improper cooking habits, excessive heating or repeated frying can also lead to the production of trans fatty acids.

Trans fatty acids have a history of more than 100 years and have been widely used in the food processing industry since the 1980s. The content of trans fatty acids is very small in natural foods. The foods containing trans fatty acids that people usually eat basically come from foods containing margarine. It has a taste similar to butter and cream, and plays a crispy role when frying food, making the food more crispy. Foods containing hydrogenated vegetable oils may contain trans fatty acids. The most common ones are baked goods such as biscuits, breads, salad dressings, fast food such as French fries, fried chicken nuggets, onion rings, etc., as well as Western-style pastries, chocolate pies, coffee companions, hot chocolate, etc. Generally, they are labeled on the product packaging as "hydrogenated vegetable oil","vegetable shortening","margarine","margarine","vegetable cream","margarine","shortening" or "vegetable fat powder", which may contain trans fatty acids. So a large proportion of the foods people buy in supermarkets today contain trans fats.

Trans fatty acids are widely used in the food industry because they not only extend shelf life, but also increase the palatability of food. Trans fatty acids can maintain a solid shape at room temperature, which will give food a beautiful appearance and make baked goods such as biscuits and breads smoother and softer. In addition, hydrogenated oils containing trans fatty acids are cheap for merchants, but their effects are comparable to natural butter.

For a long time, people have believed that artificial fats come from vegetable oils and will not be like animal fats. However, research in recent years has made people realize that trans fatty acids can cause many harm to the human body. One is to disrupt the food we eat, and the other is to change the normal metabolic pathways of our bodies. Judging from research results from