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NUTRIENT #2:
LIPIDS
LIPIDS Lipids = fats Make up 30% of daily calories Contain C, O, and H (like carbohydrates)
Lipids
Phospholipids
Fats and Oils Cholesterol
FATS AND OILS TWICE the amount of stored energy per
gram of fat (compared to proteins and carbohydrates)
Extra carbohydrates convert to fat
Insoluble in water (do not dissolve)
Composed of lipid molecules called triglycerides
Fatty acids are long chains of C and H atoms with a carboxyl group at one end
SATURATED VS UNSATURATED FATS
Saturated Fat Found in animals (animal fat)
“Bad Fat” Firm, solid fats like butter, shortening, margarine
Saturated = full of hydrogen atoms
More stable No double bonds between carbon atoms Difficult for cells to break down
Saturated Fat
Structure:
1 glycerol molecule + 3 fatty acid molecules = 1 fat molecule (triglyceride)
Fatty acid
16-18 Carbons
1 TriglycerideGlycerol
Fatty acid chain
HIGH SATURATED FATS (USE LEAST OFTEN) 1 tsp stick butter 1 slice bacon 2 Tbsp coconut, sweetened or shredded 2 Tbsp half and half cream 1 Tbsp cream cheese 1 Tbsp sour cream 1 tsp palm, palm kernel, coconut oils
SATURATED VS UNSATURATED FAT
Unsaturated Fat• Found in plants (plant fats)
• “Good Fat”– Liquid fats like canola or olive oil
• Unsaturated = some hydrogen atoms are missing
from fatty acid
• Less stable– Double bonds between carbon atoms– Weaker bonds so it is easier to break them
down
Unsaturated Fat
Structure:
MonounsaturatedPolyunsaturated
1 double bond 2 double bonds
HIGH MONOUNSATURATED FATS (CHOOSE MOST OFTEN) 1/8 avocado 1 tsp olive, canola, peanut oils 8 large black or green olives, stuffed ½ oz most nuts 2 tsp tahini paste 4 pecan halves 1 Tbsp sesame seeds
HIGH POLYUNSATURATED FATS (CHOOSE MORE OFTEN) 1 tsp stick or tub margarine 1 Tbsp reduced fat, light or nonfat
margarine 1 tsp mayonnaise 1 Tbsp reduced fat mayonnaise 4 English walnut halves 1 tsp corn, soybean, safflower,
sunflower oil 1 Tbsp salad dressing 2 Tbsp reduced fat salad dressing 1 Tbsp pumpkin or sunflower seeds
PHOSPHOLIPIDS Similar to triglycerides, but one fatty
acid group is replaced by a phosphate group
Phosphate end is POLAR (dissolves in water)
Fatty acid end is NON-POLAR (does not dissolve in water)
Main component of cell membranes
PHOSPHOLIPIDStructure
Dissolves in water (hydrophilic)
Insoluble in water (hydrophobic)
CHOLESTEROL A multiple ring structure
Insoluble in water (does not dissolve)
Part of cell membrane
Cholesterol build-up in arteries has been shown to contribute to heart disease
CHOLESTEROLStructure
TRANS-FATTY ACIDS Un-natural products known to be detrimental
to your health
Found in hydrogenated foods (eg. vegetable oil)extra hydrogen is added
When oil is hydrogenated, we cannot control where the hydrogen atoms are added chemically
“CIS” FATS Both H atoms are added to the same
side of structure
Exist naturally
“TRANS” FATS One H atom adds to one side of the
structure and the other atom to the other side
Do not exist naturally (very few exceptions)
Shape of the molecule is vital to its function
“CIS” VS “TRANS” FATS “Cis” fats are curved
Cannot solidify at room temp (ex. Oils)
“Trans” fats are straight in structure Can solidify at room temp (ex. Margarine)
Trans Fat is Everywhere
AVOIDING TRANS FATS1. Avoid all products with hydrogenated oil
as an ingredient
2. Use only natural vegetable oil or animal-based fats (butter, lard, drippings) for cooking
3. If there is not a nutritional label on the food you buy, beware!