1.8 KiB
1.8 KiB
- Lipids are a class of nutrients that do not dissolve in water.
- They will dissolve in organic solvents
- Oil is less dense than water, so it will rise to the top of a solution
- Major functions of lipids in the body include
- Providing and storing energy
- forming and maintaining cell membranes
- producing steroid hormones
- insulating the body
- cushioning the body against bumps and blows
- forming body contours
- absorbing fat soluble vitamins and phytochemicals
Fatty Acids
A fatty acid is a hydrocarbon chain found in lipids; one end of the chain forms a carboxylic acid, and one end forms a methyl group.
-
Short chain fatty acids have 2 to 4 carbons
-
Medium chain fatty acids have 6 to 12 acids
-
Long chan acids have 14 to 24 carbons
-
Fatty acids are identified by:
- The number of carbon atoms
- The type of bond between carbon atoms
-
Saturated fatty acid (SFA) Every single carbon atom is filled with hydrogen atoms
-
Unsaturated fatty acid is a fatty acid that is missing hydrogen atoms and has one or more double bonds within the carbon chain
- Monounsaturated (MUFA)
- Has one double bond within the carbon chain
- Polyunsaturated (PUFA)
- Fatty acid that has two or more bonds within the carbon chain
- Monounsaturated (MUFA)
-
Essential fatty acids are fatty acids that must be supplied by the diet
- Linoleic acid - 18 carbon omega-6 fatty acid found in vegetable oils
- Alpha-linolenic acid - 18 carbon omega-3 fatty acid, found in flaxseed, walnuts
- Precursor for
- Eicosapentaonoic acid (EPA) - 20 carbons
- Docosahexaenoic acid (DHA): 22 carbons
- Both acids are found mainly in fatty fish
- Essential fatty acids are needed for growth and healthy cell membranes, especially in the brain.