Question

Major function of PUFA is
a. Supply of essential fatty acids
b. Lowering of cholesterol level
c. Prevent atherosclerosis
d. All the above

Answer 1

Hint: Polyunsaturated fatty acids (PUFA) are the fatty acids that have two or more double bonds in their backbone chains of carbon. It includes many essential fatty acids. Some examples of PUFA are Alpha-linolenic acid (ALA), Hexadecatrienoic acid (HTA), etc. which are omega-3 fatty acids.

Complete answer:
The importance of PUFAs for humans can be understood by knowing the fact that a subgroup of it, known as essential fatty acids (EFAs) cannot be synthesized in our body, such as Alpha-Linolenic Acid, so they must be taken as food to fulfil their requirement. Also, they are important for normal growth and functioning of vital organs such as the heart and brain. Thus, PUFA helps in maintaining supply of essential fatty acids.

Saturated fatty acids are harmful for the body as they increase the cholesterol level, and so should be replaced by unsaturated fatty acids like PUFA in our diet. This replacement lowers the concentration of low-density lipoproteins in the liver as unsaturated fatty acids are directly transported for oxidation and no remnant of lipoprotein is left. Thus they are helpful in lowering the cholesterol level.

Atherosclerosis is a disease caused by deposition of fats and cholesterol in the artery walls that causes difficulty in the flow of blood, which can lead to many serious problems. Plaque is a type of cholesterol that deposits inside the arteries during atherosclerosis. If PUFA is taken, it lowers the cholesterol level and eventually prevents this condition.

From the above discussion we can conclude that PUFA maintains the supply of essential fatty acids, lowers the cholesterol levels, and thus prevents atherosclerosis.
Hence, the correct answer is option (D).

Additional information:
Polyunsaturated fatty acids can be classified into two types, based on the position of the first double bond, as omega-3 and omega-6 fatty acids. In the omega-3 family, the first double bond is present at the third carbon from the end having methyl group; and the first double bond in omega-6 family is present at the sixth carbon from the end having methyl group.

Note: Polyunsaturated fatty acids are generally liquid at the room temperature and so are considered oils. They are present mostly in food items like fish and fish oils, oils extracted from plants, seeds and nuts. Taking polyunsaturated fats in moderate amounts can benefit in maintaining good health.