Lipids are a broad group of biomolecules that include fats, oils, hormones and structural molecules. They perform a variety of functions such as
- Storing and providing energy
- Storing vitamins (Vit A, Vit E, Vit D and Vit K)
- Regulating body temperature
- Cushioning vital organs
- They help in building cell membranes
- Transmitting nerve impulses
Primarily, there are three types of lipids. They are
1. Phospholipids: Phospholipids are a type of fat that make up the outer layer of our cells. They act as a boundary or fence and allow entry or exit of nutrients and substances. Phospholipids also have other substances embedded in them, such as cholesterol.
2. Sterols: Sterols are a group of lipids found in animals, plants and fungus. The sterols found in animals are called cholesterol, those found in plants are called stigmasterol and those found in fungus are called ergosterol. They are slightly different to each other in their chemical structure. In humans, cholesterol is made in the liver and is vital for producing hormones, vitamin D and bile salts. The different types of cholesterol are
a) High-Density Lipoprotein (HDL), also known as good cholesterol.
b) Low-Density Lipoprotein (LDL), also known as bad cholesterol.
3)Triglycerides: Triglycerides are a type of fat that comes from food and other types of fat you eat. The extra calories you consume gets converted to triglyceride, which is then transported by lipoproteins to fat cells, where it is finally stored. Think of it this way, the fats that develop in your belly and thighs are triglycerides.