The membrane that surrounds a cell is made up of proteins and lipids. Depending on the membrane's location and role in the body, lipids can make up anywhere from 20 to 80 % of the membrane, with the remainder being proteins. Cholesterol, which is not found in plant cells, is a type of lipid that helps harden the membrane.

What are Lipids?

Lipids are molecules containing hydrocarbons. They are the building blocks of the structure and function of living cells, and important sources of energy. Lipids are a group of fats and fat-like substances. Monitoring & maintaining healthy levels of 'Good' (HDL) lipids is important in staying healthy.

Examples of lipids- fats, oils, waxes, certain vitamins, hormones and most of the non-protein membrane of cells.

How are Lipids Useful?

Lipids are useful to living organisms as they release large amounts of energy.

What are Some Sources of Lipids?

Lipid molecules are extracted from plants and animals. Fats (and the fatty acids from which they are made) belong to this group.

Our body extracts Lipids from the dietary fats. Numerous biosynthetic pathways also break down and synthesize lipids in the body.

Some essential lipids can only be obtained from our diet. The main biological functions of lipids include storing energy as lipids may be broken down to yield large amounts of energy.

What Do The Numbers Mean?

Your lipid profile part of a cardiac risk assessment that helps to assess your risk of heart disease and to help doctors make decisions about what treatment may be best for you if there is borderline or high risk.

For total cholesterol:

200 milligrams per deciliter (mg/dL) or less is normal.

201 to 240 mg/dL is borderline.

More than 240 mg/dL is high.

For HDL ("good cholesterol"), more is better:

60 mg/dL or higher is good -- it protects against heart disease.

40 to 59 mg/dL is OK.

Less than 40 mg/dL is low, raising your chance of heart disease.

For LDL ("bad cholesterol"), lower is better:

Less than 100 mg/dL is ideal. 100 to 129 mg/dL can be good, depending on your health.

130 to 159 mg/dL is borderline high.

160 to 189 mg/dL is high.

190 mg/dL or more is very high.