FAT and its Type Short Notes

Dietary fat provided energy and essential fatty acids, serves as a vehicle for fat-soluble vitamins and facilitates their absorption.

Fats are triglycerides and any of several fatty acids. Fats may be either solid or liquid at room temperature.

Fat provides high energy value 9Kcal/g as compared to carbohydrates or proteins 4Kcal/g.

Fatty acids, used for generation of cellular energy, synthesis of phospholipids, which are required for cell membrane of each and every call.

Fat also essential in development of central nervous system and decrease the risk of coronary heart diseases, diabetes and cancers.

Depending on their composition and chemical structure fats are divided into:

• Saturated fatty acid

• Unsaturated fatty acid

Saturated Fatty Acids

Saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. the chain of carbon atom is fully “saturated” with hydrogen atoms.

Foods containing a high proportion of saturated fat include animal fats such as cream, cheese, butter, and ghee as well as certain vegetable products such as coconut oil, cottonseed oil, chocolate, and many prepared foods.

Unsaturated Fatty Acid

An unsaturated fat is a fat in which there is at least one double bond within the fatty acid chain.

A fatty acid chain is

1. Monounsaturated if it contains one double bond

2. Polyunsaturated if it contains more than one double bond.

In cellular metabolism, unsaturated fat molecules contain somewhat less energy than an equivalent amount of saturated fat.

Foods containing unsaturated fats include avocado, nuts, and vegetable oil. Most food contains both unsaturated and saturated fats.

It is a polyunsaturated omega-6 fatty acid, belongs to essential fatty acids.

The body cannot synthesize linoleic acid from other food components.

It is a colorless liquid at room temperature.

LA is used in the biosynthesis of arachidonic acid (AA) and thus some prostaglandins.

It is found in the lipids of cell membrane.

Linoleic acid is an essential fatty acid that must be consumed for proper health. A diet only deficient in LA causes mild skin scaling, hair loss, and poor wound healing.

Linolenate is often found in vegetable oils; these are reported as the fatty acid:

• α-Linolenic acid, an omega-3 (n-3) fatty acid

• ϒ-Linolenic acid, an omega-6 (n-6) fatty acid

Cholesterol is an organic molecule. It is a sterol or modified steroid, and an essential structural component of animal cell membranes that is required to establish proper membrane permeability and fluidity.

Cholesterol also serves as a precursor for the biosynthesis of steroid hormones, bile acids, and vitamin D.

Cholesterol is a principal sterol synthesized by animals; in vertebrates it is formed predominantly in the liver.

Major dietary sources of cholesterol include cheese, egg yolks, beef, pork, poultry, fish, and shrimp. Human breast milk also contains significant quantities of cholesterol.