Lipids Flashcards
Lipids Definition
any class of fatty acids or are insoluble in water but soluble in organic solvents
Lipids Function
- source of energy
- component of cell membranes
4 Types of Lipids
triglycerides
fatty acids
phospholipids
sterols
Triglycrides
3
90% of dietary lipids
energy and fatty acid storage (this is main fat of our body)
structure: glycerol and 3 fatty acids
Fatty Acids
long chain of carbon atoms with a methyl group (CH3) at one end and a carboxyl group (COOH) at the other end of the chain
Fatty Acids - Length of Chains
long - 14C
very long - +20C
Saturated Fat
with hydrogen no bonds
eg. coconut oil, butter, palm oil
Fatty Acids - Double Bonds
affects melting point
- saturated
- monounsaturated
- polyunsaturated
- cis vs trans
LCPUFA’s
Long Chain Polyunsaturated Fatty Acids
Monounsaturated
1 double bond
eg. olive, canola and peanut oil
Polyunsaturated
more than one double bond
eg. safflower, flaxseed, walnut, sunflower, corn and soybean oil
Essential Fatty Acids
humans are not able to make a double bond with the first 6 carbons from the methyl end so we need to get this is the diet
cis bonds - linoleic and linolenic acids
Phospholipids
Make up 5-10% of dietary Lipids
structure: glycerol backbone - fatty acids (doesn’t like water)- phosphate group (like water)
Where Double Bond Is
position of first double bond from the methyl end
eg C18:1n9
= 18 carbons and one double bond on the 9th carbon from methyl end
Sphingolipids
type of phospholipid found in brain and nervous tissue
Prostaglandins
type of phospholipid and used for signalling, removes pains
Energy from Sat Fat in the Diet
less than 10%
Sterols
have a multiple string structure
- found in plant foods
Lipid Digestion
heat breaks it up in the stomach
bile from gallbladder emulsifies fat
Lipoprotein
transport fat molecules in water
Fat Absorption and Lipid Transport Process Involves
Chylomicron
Very Low Density Lipoprotein (VLDL)
Low Density Lipoprotein (LDL)
High Density Lipoprotein (HDL)
Chylomicron
delivers dietary lipids from the intestine to peripheral tissue and the liver
Very Low Density Lipoprotein (VLDL)
Delivers lipids from the liver to peripheral tissues
Low Density Lipoprotein (LDL)
Transports Cholesterol to peripheral tissues and the liver
High Density Lipoprotein (HDL)
transports cholesterol from tissue and transports to liver and lipoproteins
Type of Fat Eaten can Influence ….
fats in the body
CVD Risk Factors
many of them can be modifiable from the diet
% of Women in the world that deaths are from CVD
35%
CVD and Sat Fat
as sat fat increases so does the risk fo CVD but after 10% is palteos doesn’t make risk anymore hence the RDI
NZ Margarine
less double bonds more sat fat
cis turns to trans fat which aren’t good for heart so this is illegal in NZ
