Fats Flashcards
Lipids
“Good” (unsaturated)
- Eat in moderation
“Bad” (saturated fat and trans fat)
- Limit
What are the three classes of lipids?
Triglycerides (fats and oils)
Phospholipids ( e.g., lecithin)
Sterols ( e.g., cholesterol)
Triglycerides
Approximately 98% of fat in foods
Made of carbon, hydrogen and oxygen
Fatty Acids
Basically chains of carbon atoms with hydrogen atoms attached.
Saturated fatty acid
When all carbon atoms have four single bonds
“Saturated” with hydrogen
Unsaturated fatty acid
Does not have all the hydrogen atoms it can potentially hold
One or more double bonds from between carbon atoms in the chain
TRUE OR FALSE: All food fats contain a mixture of saturated, monounsaturated, and polyunsaturated fatty acids
TRUE
TRUE OR FALSE: Saturated fats are liquid at room temperature
FALSE
They are solid at room temperature
Vegetable fats that are saturated are:
- Palm oil
- Palm kernel oil
- Coconut oil
Saturated fats are
“bad” fat because it raises cholesterol levels
Raises total and LDL cholesterol levels
TRUE OR FALSE: Unsaturated are liquid at room temperature
TRUE
Monounsaturated fats are predominately found in
Olives Olive oil Canola oil Peanut oil Avocado Cashews Almonds Other nuts
Polyunsaturated fats are predominately found in
Corn Soybean Safflower Cottonseeds oils Fish
Unsaturated fats are
“Good fats” because the lower LDL cholesterol and raise HDL cholesterol
TRUE OR FALSE: Position of the double bond determines essentiality of fatty acid
TRUE
Linoleic acid
The essential n-6 fatty acid
Abundant in plants
Alpha- linolenic acid
The essential n-3 fatty acid
Found in flaxseed, canola, soybean, and walnut oils and in nuts, especially walnuts.
Can covert EPA AND DHA in the body
Referred to as “fish oils”
TRUE OR FALSE: Degree of unsaturation influences the stability of fats.
TRUE
Polyunsaturated fats are most susceptible to
Rancidity
Food manufacturers may add _____ or _____ to
prolong shelf life
Antioxidants
Hydrogenate
Hydrogenation
A process where hydrogen atoms are added to polyunsaturated oils to saturate some of the double bonds so it is less susceptible to rancidity and has improved function.
Rancidity
Spoiling of fats through oxidation
More double bonds therefore more susceptible to oxidation and rancidity
Functions of fat in the body
Fuel the body with energy
Insulate and cushion internal organs
Helps regulate body temperature
Facilitate the absorption of fat soluble vitamins
Phospholipids
Structural components of cell membranes that facilitate the transport of fat soluble substances
Precursors of prostaglandins
Cholesterol
waxy substance whose carbon, hydrogen and oxygen molecules are arranged in a ring
TRUE OR FALSE: Cholecystokinin stimulates the gallbladder to release bile which prepares fat for digestion
TRUE
TRUE OR FALSE: Most fat digestion occurs in the stomach
FALSE
It occurs in the small intestines
TRUE OR FALSE: End products of digestion are absorbed into
intestinal cells.
TRUE
– Small amount is excreted in feces.
Chylomicrons
These facilitate lipid absorption
They are too large to be absorbed through lymph fluid so they enter the blood stream through thoracic duct next to the heart
TRUE OR FALSE: Lipoproteins Transport Fat Through the Lymph and Blood
TRUE
TRUE OR FALSE: More protein, higher density in lipoproteins
TRUE
Role of HDLs
Transport cholesterol from body cells and deliver it to the liver disposal
Role of LDLs
Transport cholesterol to cells, in some cases into the arterial lining
Role of VLDLs
Deliver fatty acid made in the liver to the cells
Catabolism of fatty acids increases when
- Carbohydrate intake is inadequate (e.g., while
on a very-low-calorie diet). - Catabolism of fatty acids is unavailable (e.g.,
in the case of uncontrolled diabetes).
What happens to the end products of fat metabolism? They are: a. Stored in adipose tissue b. Stored in the liver c. Absorbed into intestinal cells d. Absorbed into the bloodstream
c. Absorbed into intestinal cells
Rationale: Micelles deliver fat to the intestinal
cells
Function of Fats in foods
- Imparts it own flavor
- Transfer heat to rapidly cook food
- Absorbs flavors and aromas
- Adds juiciness to meats
- Adds texture to many foods
TRUE OR FALSE: Fat in dairy products is predominately saturated, and full-fat products
have more cholesterol than in the lower-fat options.
TRUE
TRUE OR FALSE: “Red meats”—namely, beef, pork, and lamb—are higher in
saturated fat than the “white meats” of poultry and seafood.
TRUE
Sources of omega 3
Salmon Mackerel Sardine Tuna Oyster Shrimp Chia seeds Canola oil Walnuts Flax seeds Spinach
Acceptable Macronutrient Distribution Range (AMDR) for fat
20% to 35% of total calories for adults.
Symptoms of essential fatty acid deficiency
growth failure reproductive failure scaly dermatitis kidney liver disorders.
