Chapter 5 Flashcards
What is Fat made of (chemicals)
C, H, and O
What was the trend for fat diets in the 1980’s?
Avoid Fat
What the trend for fat diets now?
Eat lots of fat
What are Lipids?
A family of organic compounds that are not soluble in water
What are the 3 types of lipids?
1)Triglycerides
2)Phospholipids
3)Sterols
What are the two functions of the body’s fat?
1)Body chief storage form for excess food energy
2)Provides much of the energy needed for the body’s work
What are fat cells called?
Adipose Cells
How are adipose cells specialized for fat storage compared to other body cells?
Adipose cells can expand and multiply
Other cells have limited fat storage
How is adipose (fat) tissue active tissue?
Secretes hormones and produces enzymes that influence food intake and affect the body’s use of nutrients
True or False Fat is a more efficient form of energy than carbs and why?
True, fats pack more tightly together without allowing more fat to be stored compared to glycogen
What are 3 functions of fat other than energy?
Shock Absorbers (Surround vital organs)
Thermoregulation (insulates body)
Cell Membranes (lipids are a component of cell membranes)
Why is fat important for the body?
1)Needed Nutrients
2)Aids in the absorption of some phytochemicals
3)Essential Fatty Acids
4)People naturally like high-fat food
What is Satiety?
Feeling of fullness of satisfaction that people experience after meals
How does fat contribute to Satiety?
Trigger series of physiological events that slow the emptying stomach and promote satiety
What is the chemical makeup of triglycerides?
3 fatty acids + glycerol
What is the backbone of triglycerides?
Glycerol
Saturated Fatty Acids have ____ carbon bonds
single bonds
Unsaturated fatty acids have __ carbon bonds?
Double , triple, etc. carbon bonds
Omega-3 and Omega -6 Fatty acids are saturated or unsaturated?
PolyUNSATURATED
Polyunsaturated is?
More than one carbon carbon double + bond
Monounsaturated is?
Only one carbon-carbon double + bond
What does a degree of saturation effect?
Melting Temperature
(more unsaturated =more liquid fat at room temp)
(More saturated = more solid at room temp.)
What is the most common chain length in diets?
Long-chain fatty acids (12-24 carbons)
-Meat Seafood and Veggie oils
Where are medium (6-10) chain and short chain fatty acids found (less than 6)
Dairy Products
We should _______ saturated fats and _______trans fats?
Limiting
Instead of eating saturated and trans fats use?
Monounsaturated fats and polyunsaturated fats
T or F: The harder the fat the poorer the choice?
True
Animal and Tropical fats are majority saturated or unsaturated?
Saturated
Veggie oils are rich in saturated or unsaturated fatty acids?
UNSATURATED
Coconut and Palm oils are saturated or unsaturated fatty acids?
Saturated
What is hydrogenation?
A chemical process by which hydrogens are added to monounsaturated or polyunsaturated fatty acids to reduce the number of double bonds, making the fats more saturated and more resistant to oxidation.
How are trans-fatty acids formed?
A polyunsaturated fat is rarely fully hydrogenated: means some double bonds remain which change from cis to trans
Where are natural trans fats found?
Milk and Meat products but still declared on labeled
Where are trans fats declared?
Nutrition Facts label under trans declaration
What are the 3 advantages of hydrogenation?
1)Protects against oxidation by making polyunsaturated fats more saturated
-Increases shelf life
2) Alter the texture of food by making liquid veggie oils more solid.
-Improved food texture
3)Hydrogenated oil has a higher smoke point
-More stable in high cooking temp.
What are 2 alternative to hydrogenation?
1)Add BHA and BHT to react with oxygen before it can do damage
2)Keep Refrigerated
T of F Partially hydrogenated oils (PHO) were banned in 2018? (trans fats)
True
What are phospholipids made of chemically?
2 fatty acids + glycerol + a phosphorus containing molecule
What is a emulsifier?
A substance that mixes with both fat and water and disperses that fat in the water forming an emulsions
(Oil and Vinegar)
T or F Phospholipids are Emulsifiers?
True
What is Lecithin?
Type of fat that plays in a role in a cells membranes along with phospholipids
(Mayo, Eggs, Peanuts)
Provides kcal cuz its a fat
True or False Lecithin can be used to promote health?
Not special ability to promote health because the body makes all it needs
How are phospholipids considered emulsifiers?
Help fat travel back and forth across the lipid-containing membrane of cells into the water fluid on both sides
What are sterols?
Large molecules consisting of interconnected rings of carbon atoms with side chains of carbon, hydrogen and oxygen
What are two types of sterols?
Cholesterol: from animals
Phytosterols: From plants
How do phytosterols lower cholesterol?
Compete with cholesterol for absorption
Vitamin D and Sex hormones are what type of lipid?
Sterols
What sterol is responsible for bile production?
Cholesterol
Why is the emulsification of fats via by important?
Allows fats to contact enzymes in watery fluid to split the fatty acids from the glycerol backbone for absorption (monoglycerides, free fatty acids and glycerol)
-Lipids then cling together, surrounded by bile
T or F: Cholesterol is a essential nutrient?
False
How is the mouth used for digestion of fats?
Lingual Lipase acts on triglycerides with short and medium chain fatty acids
How is the stomach used for the digestion of fats?
-Grinds it into finer pieces
-Gastric Lipase breaks down triglycerides
How is the small intestine used for the digestion of fats?
-Bile is secreted (CCK)
-Bile Emulsifies them
Where is bile produced?
Liver
Where is bile stored?
Gallbladder
If somebody gallbladder is removed, what is a diet recommendation?
Reduced fats as less bile to emsulify (still produced but can’t be stored)
What occurs in the small intestine after the bile has emulsified the fats?
Bile shuttles lipids across the mucous layer to the absorptive cells in the intestinal villi.
-Cell extract lipids
-Bile is absorbed and reused or exit with feces
What occurs to the smaller products of lipid digestion (glycerol, short and medium chain fatty acids)
-Pass directly through cells of intestinal lining into the bloodstream then liver
What occurs to the larger products of lipid digestion? (Mono-glycerides and long-chain fatty acids)
Inside intestinal cells:
1)Reform into triglycerides and clustered together with proteins and phospholipids
2)Form Chylomicrons
3)Chylomicrons travel in lymph to bloodstream and body will take triglycerides from chylomicrons in bloodstream
What are chylomicrons?
Type of lipoprotein (largest and least dense)
What lipoproteins?
-Cluster of lipids associated with a protein
-Serve as transport vehicles for lipids in lymph and blood
Why are lipoproteins important?
Without a mechanism to keep it dispersed, large lipid globules would separate from the water blood and disrupt its normal function.
What are the four major types of lipoproteins?
1)Chylomicrons
2)VLDL
3)LDL
4)HDL
What are Very Low-density lipoproteins? VLDL
Carry triglycerides and other lipids made in the liver to body cells for their use.
What are low-density lipoproteins (LDL)?
-Transport cholesterol and other lipids to body tissues
-Made from VLDL (after done their job)
What are high-density lipoproteins (HDL)
Carry cholesterol from body cells to the liver for disposal.
What is there a increased risk of if one has a diet high in trans and saturated fats?
Heart Disease (CVD)
What are the risks of high fat diets?
1)Obesity
2)Cancer
3)CVD
LDL vs HDL in terms of size
LDL: Larger, Lighter and Richer in cholesterol
HDL: Smaller, Denser, and Packaged in more protein than LDL
LDL vs HDL in terms of cholesterol uptake and where it is carried?
LDL: Cholesterol and triglycerides from liver to tissues
HDL: Scavenges excess cholesterol and phospholipids from tissues for disposal
Elevated LDL or HDL is associated with decreased heart disease risk?
HDL (taking out of body)
Elevated LDL or HDL is associated with increased heart disease risk?
LDL (kept within body)
Heart disease is related to what in terms of lipoproteins? x2
1)Proportions of lipids the lipoproteins carry
2)Tasks the lipoprotein perform
T or F heart disease risk is associated with the type of cholesterol the lipoproteins carry?
False (cholesterol is cholesterol)
What are 3 risk factors of heart disease that cannot be controlled by heart disease
1)Increasing age
2)Being Male
3)Family history of premature heart disease
How may the food we eat raise cholesterol levels and increase heart disease risk?
Most saturated food fats and trans fats raise blood LDL cholesterol more than other food cholesterols.
What is the key for cholesterol in diet?
Moderation is key
What are the 3 ways to lower LDL cholesterol?
1)Reduce trans and sat fats
2)Weight Loss
3)Additional Soluble Fibre
T or F it is recommended to have a very low-fat diet and add more refined carbohydrates to reduce LDL cholesterol
False,
How do high levels of LDL cholesterol cause damage to the heart and arteries?
LDL is susceptible to oxidation
Oxidation of the lipid part of LDL damages heart and arteries
What could slow down LDL oxidation?
Dietary antioxidants
(Vitamins C and E, Selenium, Antioxidant phytochemical)
How to raise HDL cholesterol? x3
1)Dietary measures are generally ineffective at significantly raising its concentration
-Trans fat can lower HDL
-Saturated fat may raise HDL
2)PA can raise HDL
3)Quitting smoking can raise HDL
What % of kcalories should come from fat in your daily diet?
20-35%
What are the general diet recommendations for fats?x4
1)20-35% kcal from fat
2)Replace saturated and trans fat with monounsaturated or polyunsaturated fat
3)Fruit, Veggies and Whole Grains
(supply abundant nutrients and antioxidants along
with beneficial fibre)
4)Phytosterols
What are the 5 common characteristics of the Mediterranean Diet?
1)Low in Sat Fats
2)Very Low in Trans Fat
3)Rich in unsat fats
4)Rich in complex carbs and fibre
5)Rich in nutrients and phytochemicals
What is the Portfolio Diet?
Focuses on what you can add to your portfolio of plant foods and not what you can’t eat
What is the DASH eating plan?
Lowers blood pressure and LDL bad cholesterol
What are the two ways body fat can be used up for energy?
1)decreasing intake of food energy
2)increase the body’s expenditure of energy
What are the only two fatty acids that cannot be synthesized by the body?
Linoleic Acid and Linolenic acid: Essential Fatty Acids/Polyunsaturated fatty acids
How does Linoleic Acid and Linolenic acid contribute to the body? x6
Essential Fatty Acids
-Used by the body to make eicosanoids (regulate body functions)
-Structural and functional part of cell membranes
-Contribute lipids to brain and nerves
-Promote normal growth and vision
-Support immune cell functions
What are eicosanoids? x4
Biologically active compounds that regulate body functions
-Muscle relaxation and constriction
-Blood vessel dilation and constriction
-Blood clot formation, blood lipids
-Response to injury and infection
T or F Fatty Acid deficiency is common in North America?
False Only infnts fed fat free milk or following very low fat diets
What type of essential fatty acids is omega-6 fatty acid?
Linoleic Acid
T or F: omega-6 fatty acid foods should be consumed in moderation (veggie oils)
True
What is Arachidonic acid?
Multiple omega-6 fatty acids together
-Starting material from which a number of eicosanoids are made
What type of essential fatty acid is omega-3 fatty acid?
LinoLENIC Acid
What is a example of a omega-3 fatty acid?
Flax Seed Oil
T or F multiple of the same either omega-3 or omega-6 fatty acid can be combined to produce other products?
True
What is EPA and DHA
Multiple omega-3 fatty acids together
-Body makes limited amounts
-Abundant in fish oils (suggest fish in meals)
Why are omega-3 fatty acids important to include in diet?
Support immunity and inhibit the development of certain cancers
What is energy yielding nutrients provides most calories per bite?
Fat
Where is fat seen in our diet: Meat?
Generally contains fat
Where is fat seen in our diet: Dairy?
Contain fats but is often removed
Where is fat seen in our diet: Grain?
Sometimes naturally low in fat
(Sat fat and trans fat may be added during manufacturing, processing or cooking)
Where is fat seen in our diet: Fruits and Veggies
Unprocessed: Fat free except avo and olives
If trying to reduce added fats in your diet do these two things.
1)Make sure the fat is dectable
2)Use a strongly flavoured fat, a little goes a long way
Why is soft margarine better than butter? x2
1)Non-hydrogenated - less likely to elevate blood cholesterol than the saturated fats of butter.
2)Contain added phytosterols (lower cholesterol by competing with it for absorption)
What is the difference between soft margarine and hard margarine?
Hard: hydrogenated fats (sat fats and trans fats
Soft: Non-hydrogenated
What are fat replacers?
replace some or all the functions of fat
What are the 2 ways fat replacers work?
1)Contain artificial fats
2)Use conventional products in unconventional ways to reduce fat and calories (bake vs fry, whip air into foods)
What are the 3 types of fat replacers?
1)Carbohydrates: Fruit purees or starches
2)Fibres: viscous fibres may provide texture similar to natural fat
3)Proteins: micro particulate protein or fermented whey
What is artificial fat?
Zero energy fat replacers that are chemically synthesized to mimic the sensory and cooking qualities of natural fats but are totally or partially resistant to digestion
What is Olestra?
Sucrose Polymer: Fat Replacers
-Not allowed in Canada
What are 4 problems with low-fat diets?
1)Difficult to maintain
2)Not necessarily low-calorie diets
3)Diets in carbs (especially sugar and low in fibre -Causes triglycerides to rise)
4)May exclude nutritious foods that provide the essential fatty acids, phytochemical and vitamins and minerals
Why were low-fat diets recommended for so long?
Focus on total fat reduction to reduce sat fat
How many foodborne illness cases in Canada each year?
4 million
What the 6 common symptoms of foodborne illness?
-Stomach Cramps
-Nausea
-Vomiting
-Diarrhea
-Fever
-Death
Who is most vulnerable to foodborne illness? x4
-Preggo
-Infants and kids under 5
-Individuals 60 and over
-Weak immune system
How do microbes cause foodborne illness (2 ways)?
1)Foodborne Infection
2)Food intoxications
What are foodborne infections?
Caused by eating foods contaminated with infectious microbes
What are food intoxications?
Caused by eating foods containing natural toxins or microbes that produce toxins
What is Listeriosis?
Illness from bacteria that live in the intestines of animals and humans as well as soil, vegetation and water
What is e. coli?
A bacteria found in human and animal intestines
What is botulism?
Disease caused by botulinum bacteria that produces toxin botulin (anaerobic environment with low acidity)
What is the most common food intoxication?
Staphylococcal Food Poisoning
What is staphylococcal food poisoning come from?
Skin and Nasal passages
What type of food illness Vibrosis?
Food Borne Infection
What type of food illness Staphylococcal food poising?
Food Intoxication
What type of food illness Botulism?
Food Intoxication
What type of food illness E.Coli?
Food Borne Infection
What type of food illness Salmonellosisis?
Food Borne Infection
What type of food illness Listeriosis?
Food Borne Infection
What type of food illness Hep A?
Food Borne Infection
What are the 4 ways to prevent foodborne illnesses?
1)Clean
2)Separate
3)Chill
4)Cook
When storing leftovers they should be refrigerated within?
2 hours
T or F Meat should be deboned and stored in small pieces before refrigerating
True
Why does travelers’ diarrhea often occur form?
Contaminated Water
Undercooked ground beef
Raw Foods
Unpasteurized raw cheeses and milk
