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LIPIDS
lipids, triglyceride, unsaturated, saturated, phospholipids, cholesterol, wax, steroid
canola oil, butter, salad dressing, mayonnaise, avocado
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Lipids
Lipids are hydrophobic –”water fearing”
Includes fats, waxes, steroids, & oils
Do NOT mix with water
FAT MOLECULE
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Fats
Dietary fat consists of the molecule triglyceride composed of glycerol and three fatty acid chains
Glycerol
Fatty Acid Chain
Dehydration/Condensation links the fatty acids to Glycerol
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Triglyceride
Monomer of lipids
Composed of Glycerol & 3 fatty acid chainsGlycerol forms the “backbone” of the fat Organic
Alcohol
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Triglyceride
H2C
HC
H2C
O
O–C
O
O–C
O
O–C
H2O H2O H2O
Water from Condensation/dehydration synthesis
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Types of Fatty Acids
Unsaturated fatty acids (better fats ie: oils)
Contain a double bond between carbons (liquids)
Saturated fatty acids (bad fats ie: shortening)
All single bonds between carbons (solids)
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Fats in Organisms
Most animal fats have a high proportion of saturated fatty acids & exist as solids at room temperature (butter, margarine, shortening)
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Fats in Organisms
Most plant oils tend to be low in saturated fatty acids & exist as liquids at room temperature (oils)
Polyunsaturated – many double bonds
*Best Choice*
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Trans Fat (the “Ugly” fat)
•Usually made from cis-unsaturated fats in an industrial process called “hydrogenation”
•“Hydrogenation” – conversion of unsaturated to saturated (solids)
•Have longer shelf life
•They increase LDL cholesterol levels and decrease HDL cholesterol levels
•Harmful as saturated fats – or WORSE!
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Cholesterol•NOT a “bad guy!” Our bodies make about 2 g of
cholesterol per day, and that makes up about 85% of blood cholesterol.
•Only about 15% comes from dietary sources.
•Found naturally in cell membranes and used to synthesize certain hormones – sex hormones
Two types of Cholesterol
LDL’s - Low Density Lipoproteins (bad)
HDL’s – High Density Lipoproteins (good)*reducing processed breads, pasta, and other highly
saturated foods can help decrease LDL accumulation*
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30% of the total energy intake should be in the form of fats.
– carbohydrates and proteins (4kcal/g) of energy
–9kcal/g for every gram of fat energy
__g of Carbs X 4kcal/g = __kcal __g of fat X 9kcal/g = __kcal __g of proteins X 4kcal/g = __kcal
Fats
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SteroidsThe carbon skeleton of steroids is bent to form 4 fused ringsCholesterol is the “base steroid” from which your body produces other steroids
Estrogen & Testosterone are also steroids
Cholesterol
TestosteroneEstrogen
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