Chap 6: Fats Flashcards
Sources of Fat
Dairy, Meat, Eggs (Satura./Unsatur, Lipoprotein, and triglycerides)
Oils, Cakes, Pastries, Plants
(nuts, cereal grains, and fruit(avocado))
Functions of Fat
9 kcal
Enhances palatability (aroma, texture & mouthfeel)
Aids in fat-soluble vitamin absorption
Hormone precursors
Provides insulation from cold
Protects body organs
Energy reserve
Why are fats more calories
C bonded to H (lipids)
* Compared to Carbs (C bonded to O)
Types of Fat (3)
Triacylglycerols
Phospholipids
Glycolipids
Triacylglycerols (triglycerides)
Principal dietary lipids stored in fats stored in fats stores in body consisting of fatty acids
* Saturated and unsaturated
*Glycerol
Phospholipids contains
phosphoric acid
Glycolipids
contains 1-4 linked monosaccharide residues beyond by glycosyl linkage to lipid
* Diacylglycerol or Sphingosine
Fatty acids and derivatives
Triglycerides (3 fatty acids)
Diglycerides (2 fatty acids)
Monoglycerides (1 fatty acid)
Cholesterol
waxy substance found in blood
Lipoprotein
group of soluble proteins that combine with and transport fat in the blood
HDL
High-density lipoprotein (Good)
(Contains higher amounts of protein)
*Pickup cholesterol for removal or recycling
LDL
Low-density lipoprotein (Bad)
(Contains higher amounts of lipid)
*Deliver cholesterol to cells
VLDL
Very-low-density lipoproteins (Bad)
*Delivers triglycerides to cells
Fatty Acids contain
- carboxylic (carboxyl group)
- aliphatic (straight-chained chemical structure)
Most naturally occurring fatty acids
have a chain of an even number of carbon atoms (12-28)
(Important sources of fuel * when metabolized yield large quantities of ATP)
SCFA
Short-chain fatty acids
FA with tails of fewer than 6 carbons (e.g. butyric acid)
MCFA
Medium-chain fatty acid
FA with tails of 6-12 carbons (e.g. capric acid)
LCFA
Long-chain fatty acids
FA tails with 13-21 carbons (e.g. arachidic acid)
VLCFA
Very long chain fatty acid
FA tails with longer than 22 carbons (e.g. cerotic acid)
MCT
(Source & Trending)
Medium-Chain Triglycerides
(tails 6-12 carbons)
* Coconut
*Keto diet (high fat & low carb diet)
MCT promotes
the release of leptin & may induce thermogenesis
Saturated Fatty Acids
- No double bonds
- Fully saturated with H
- Cause the level of LDL cholesterol in the blood to rise
- Solid at room temp
Ex. butter, cocoa butter, palm/coconut oil, etc.
Unsaturated Fatty Acids
- Fatty acids in which some of the hydrogen atoms in each molecule has been replaced by double bonds
- Liquid at room temp
- Unstable - more susceptible to oxidation
Monounsaturated (olive oil)
Polyunsaturated (nuts, fish)
Monounsaturated Fat
-one free carbon-hydrogen bond
-Lower LDL & Raise HDL
-Considered “healthy” fats
-Olive oil & Canola oil
-Liquid at room temperature
Polyunsaturated Fat
-Many free carbon-hydrogen bonds
-Lower LDL & does NOT affect HDL
-Considered “healthy” but not as healthy as monounsaturated
-Liquid at room temperature
-vegetable oils, avocados, nuts, seeds & many fish
Trans Fats
-one or more double bonds in trans instead of cis
-naturally occurring (gut of animals
-synthetic (hydrogenation process)
- increased LDL
Example of Saturated (acid)
Stearic acid (found in butter)
Example of Unsaturated (acid)
Linoleic acid (found in vegetable oil
Example of Trans (acid)
trans-linoleic acid (found in some margarine)
Essential Fatty Acids
CANNOT be synthesized
-cell membrane components
-strengthen immune cells
-lubricate joints
-insulate body against heat loss
-prevent skin from drying
-provide energy
Example of essential fatty acid
Polyunsaturated fats
Most important Omegas
Omega 3/ Omega 6
Which omega is non-essential?
Omega 9
What are the two ends of a double bond?
Carboxyl (left) & Me thyl (right)
What are the two ends of a double bond?
Carboxyl (left) & Me thyl (right)
Omegas start counting on which end?
Methyl
Essential Fatty Acids: Food Sources
Fish oil, nuts and seeds
Omega 3 acids
(ALA)
(EPA)
(DHA)
Plant sources of omega 3
-Flax seed, walnut
-(ALA): can be converted into EPA and DHA
Omega 6 acids
(LA)
(GLA)
(AA)-converted to inflammatory compounds
Ratio of omegas
Ideal ratio- 4:1
western diet ration- 12:1 - 25:1
Fat Recommended Intake
-should be reduced to 30-35%
-increased unsaturated fats
-decrease saturated fats to 10%
consequences of increased fat intake
-obesity
-heart disease
-metabolic syndrome
-cancer
-diabetes
-high blood pressure
Digestion of fat
-Lipase
-Emulsification
-Bile salt
-phospholipid
-micelle
-enterocyte
-reformed triglyceride
-chylomicron
Lipids are
hydrophobic
