There are many kinds of fatty acids. So, what makes the variety of fatty acids so rich? First of all, we need to know that the basic unit of fatty acids is the hydrocarbon chain. The difference in the structure of the hydrocarbon chain causes the difference in the types of fatty acids, so that the fatty acids are divided into saturated fatty acids and unsaturated fatty acids.
What are the saturated and unsaturated fatty acids?
Both saturated and unsaturated fatty acids are a type of fatty acid, but the two are very different.
Saturated fatty acids have a zigzag linear structure, which is more attractive and has a higher melting point (the temperature at which solids are converted from solid to liquid).
The double bond in the unsaturated fatty acid is a cis structure, the molecule is curved, the structure is relatively loose, and the melting point is low. Both animal and vegetable oils contain saturated and unsaturated fatty acids, but usually animal oils contain more saturated fatty acids, and vegetable oils contain more unsaturated fatty acids. This results in animal oils being mostly solid or semi-solid at room temperature of 15 to 30 ° C, while vegetable oils are mostly liquid.
But we must be clear: you can't equalize saturated fatty acids and animal oils, and you can't equalize unsaturated fatty acids and vegetable oils. In fact, animal oils and vegetable oils have "heterogeneous". Fish oils as animal oils are liquid at room temperature because they contain more unsaturated fatty acids. Palm oil, which is a vegetable oil, is solid at room temperature because it contains a lot of saturated fatty acids. Semi-solid.
The characteristics of animal oils and vegetable oils in terms of fatty acid content determine our oil-consuming strategy.
Less intake of saturated fatty acids, more intake of unsaturated fatty acids The structure of saturated fatty acids has no double bonds on the carbon chain, which makes it more stable. The most common saturated fatty acids in the foods we usually eat are palmitic acid and stearic acid, which are high in animal fats such as lard, butter, chicken, and duck oil. However, vegetable oils also contain a lot of saturated fatty acids. Palm oil and coconut oil, which are often used as snacks for biscuits, potato chips and instant noodles, contain a lot of saturated fatty acids.
Regarding saturated fatty acids, it promotes the synthesis of cholesterol in the liver and promotes intestinal absorption of cholesterol, so it has long been considered to be an important cause of dyslipidemia. It is considered to be one of the risk factors for atherosclerosis, coronary heart disease and hypertension. If you do not add temperance and long-term excessive intake, it may also induce cancer.
Therefore, the Chinese Nutrition Society has repeatedly stressed that to control the intake of saturated fatty acids, the daily intake of saturated fatty acids per adult should be less than 10% of the total energy intake. As for those who already have dyslipidemia, fatty liver, coronary heart disease, high blood pressure or diabetes, it is even more important to reduce the intake of saturated fatty acids and keep your mouth shut.