Chapter 6 Flashcards
What are some of the primary functions of fats/lipids?
-make hormones
-add flavor and texture
-provide energy
-insulate body
-protect organs
-aid in transport and absorption of fat-soluble vitamins
-make hormones
What are the four fat-soluble vitamins?
A,D,E,K
Why are low-fat foods not always a healthy alternative to the regular version of the food?
Contain added sugars
What is leptin and how does it impact our appetite?
Hormone made by fat cells that decreases appetite
Where is leptin produced?
adipose tissue
How would leptin resistance affect someone?
decrease in ability of leptin to suppress appetite or increase your body’s energy use
What is ghrelin and how does it impact our appetite?
Hormone made by fat that increases appetite
Where is ghrelin produced?
stomach
How would the overproduction of ghrelin impact someone?
Causes severe obesity, extreme hunger, and learning difficulties
What are some high fat foods?
vegetable oil
butter
avocado
mixed nuts
peanut butter
The lipid family includes
triglycerides, phospholipids, sterols
The most common lipid found in foods and in the body?
triglycerides
What is the difference between fats and oils?
fats= solid @ room temp
oils= liquid @ room temp
What are examples of fats and oils?
Fats= butter & lard
Oils= olive oil & canola oil
Triglycerides consist of 3 ___ attached to a ___ backbone.
fatty acids, glycerol
Diglycerides
Triglyceride that has lost 1 fatty acid
Monoglycerides
Triglyceride that has lost 2 fatty acids
Animal or plant foods have saturated fatty acids?
animal foods
Animal or plant foods contain mono- and polyunsaturated fatty acids?
plant foods
What are two plant foods that contain a higher proportion of saturated fat?
coconut and palm oil
Esterification
process of attaching fatty acids to a glycerol
Ester bond
formed btw a fatty acid & a glycerol
De-esterification
release of fatty acids from glycerol
Re-esterification
reattaching a fatty acid to glycerol that has lost a fatty acid
Hydrolysis
reaction that releases fatty acids from glycerol
How do the carbon chains of fatty acids differ?
-# of carbons
-saturated with hydrogen (no bonds)
-shape of chain
How many kcal/g do all fats contain?
9kcal/g
What is the predominant fatty acid form found in the American diet?
long-chain fatty acids
Long-chain fatty acids
Carbon#: 12 or more
Food source: beef, pork, lamb and plant oils
How are they transported after absorption? lymphatic system
Medium-chain fatty acids
Carbon#: 6-10
Food source: coconut and palm kernel oils
How are they transported after absorption? circulatory system
Short-chain fatty acids
Carbon#: less than 6
Food source: milk, butter
How are they transported after absorption? circulatory system
What does it mean if a fatty acid is saturated?
-no double bonds (saturated with hydrogen)
What does it mean if a fatty acid is unsaturated?
-double bonds present
How many double bonds are in a MUFA?
one double bond
How many double bonds are in a PUFA?
at least two double bonds
Unsaturated fats are liquid at room temp bc?
Fats with double bonds are harder to stack b/c they start to curve
What is homogenization?
process of reducing a substance to extremely small particles and distributing it uniformly
What is hydrogenation?
pump hydrogen into oil so that it becomes more solid
Why did manufacturers start using hydrogenation?
extends shelf-life
What fat is formed from partial hydrogenation?
tans-fat (is illegal now)
A food can be considered trans-fat free if it contains less than?
0.5g/serving
What is the omega end?
methyl end (CH3)
What is the delta end?
carboxyl (COOH)
What does 18:2 w6 mean in terms of carbons, double bonds, and the location of the double bonds?
carbon=18
double bonds= 2
location of double bonds= 6
starts at methyl end (omega)
What does 18:2 Δ9, 12 mean in terms of carbons, double bonds, and location of the double bonds?
carbon=18
double bonds=2
location of every double bond= 9 & 12
starts at methyl end (delta)
What are essential fatty acids?
must come from food bc body cannot make them
How many essential fatty acids are there and what are they?
Alpha-linolenic acid
Linoleic Acid
ALA
-omega 3 fatty acid
-makes EPA & DHA (fetal development) and certain eicosanoids (hormone-like compounds)
LA
-omega 6 fatty acid
-makes Dihomo-gamma-linolenic acid and Arachidonic acid and certain Eicosanoids
Both ALA and LA are examples of what fatty acid?
polyunsaturated fatty acids
How do omega-3 fatty acids (EPA) impact the body?
reduces depression and risk of heart disease
proper fetal development and healthy aging
What are sources of omega-3 (EPA) fatty acids?
fish oil, breastmilk, cod liver, cold-water fatty fish
How do omega-6 fatty acids impact the body?
stimulate skin and hair growth
maintain bone health
regulate metabolism
maintain the reproductive system
What are sources of omega-6 fatty acids?
beef, poultry, safflower oil, sunflower oil, corn oil
Is the American diet more pro-inflammatory or more anti-inflammatory?
pro-inflammatory
What is DHA?
most abundant omega-3 fatty acid in the brain
functions= adequate brain development in children, impacts adult brain structure and signaling systems, nervous system development, optimal memory function
What are eicosanoids?
hormone-like compounds
What are some of the functions of different eicosanoids?
-regulate blood pressure, blood clotting, sleep/wake cycles, body temp, inflammation, stomach secretions, immune and allergic reactions
-regulate cell division rates
-maintain normal kidney function and fluid balance
-direct hormones to their targets
Monounsaturated fat sources?
olive oil, canola oil, peanut oil
Polyunsaturated fat sources?
sunflower oil, safflower oil, corn oil
Trans Fatty acids sources?
margarine, shortening, processed food
What are the functions of triglycerides?
-concentrated source of energy
-insulate and cushion vital organs, maintain body temp
-help transport essential nutrients in the bloodstream
What is hypertrophy?
cells grow in size
What is hyperplasia?
multiply in number
How does the structure of a phospholipid differ from a triglyceride?
contain a phosphate head (hydrophilic and hydrophobic) (keeps things separated)
What are the functions of phospholipids in the body?
cell membrane component and emulsifier
What is an example of phospholipid emulsifier?
lecithin
Best-known sterol
cholesterol
Functions of cholesterol?
-has ringed structures
Make:
-sex hormones
-adrenal hormones
-cell membranes
-active form of Vitamin D
-bile
Where is cholesterol found naturally?
foods of animal origin (milk, meat, seafood)
Would it be a good idea to restrict an infant’s fat intake?
No, it is important for brain development
What can happen if someone isn’t consuming enough essential fatty acids?
-diarrhea
-slowed growth
-delayed healing of wounds and infections
-flaky, itchy skin
What is the Mediterranean diet high in?
olive oil, fruits, vegetables, whole gains, beans, nuts and seeds
What foods are limited in Mediterranean diet?
cheese, yogurt, fish, eggs, and red meat
What foods are consumed widely in Mediterranean diet?
olive oils
What are some benefits of the Mediterranean diet?
-lower risk of disease
-increased longevity
-lower blood pressure
-lower risk of becoming obese/overweight
How might diets high in ultra-processed foods and simple sugar impact blood lipid levels?
Can elevate blood lipid levels which increases risk of cardiovascular disease
Where is fat digested?
mouth, stomach, small intestine
What is gastric lipase?
breaks triglycerides into monoglycerides, diglycerides, and free fatty acids
What is CCK?
triggers bile release
What are lipoproteins?
lipids transported in blood
What are lipoproteins made of?
lipids covered with a shell of proteins, phospholipids, and cholesterol
Which lipoprotein transports dietary fats?
chylomicrons
Chylomicron
primary component: triglyceride
key role: carries dietary fat from the SI to the cells
VLDL
primary component= triglyceride
key role: produced by liver- release triglyceride to cells
VLDL-> IDL-> LDL?
less triglyceride; more cholesterol
LDL
BAD Cholesterol
Primary component: cholesterol
key role: carries cholesterol made by the liver and form other sources to the cells
HDL
GOOD cholesterol
primary component: protein
key role: helps remove cholesterol from the cells and in turn excrete cholesterol from the body (reverse cholesterol transport)
What is lipoprotein lipase?
enzyme attached to the inside of cell membranes
role: hydrolyzes triglycerides from the chylomicrons
Receptor Pathway for Cholesterol uptake?
- LDL removed from blood by LDL receptors
- LDL broken-down into free cholesterol and protein
- cell is full and receptors stop taking LDL
Atherosclerosis
- LDL is oxidized by free radials
- plaque formation in arteries
High polyunsaturated fat intake
-increase amount of cholesterol deposited in arteries
-impair the immune system
Excessive omega-3 fatty acid intake
-impair immune system
-allow uncontrolled bleeding= hemorrhagic stroke
Non-modifiable risk factors
age, gender, race, genetics
Modifiable risk factors
blood triglyceride and cholesterol levels, hypertension, smoking, physical inactivity, obesity, diabetes and other disease
What are some dietary changes that can be made to prevent CVD?
eat fruits, vegetables, nuts, and plant oils (increase soluble fiber intake)
consume foods with antioxidants
Total cholesterol optimal blood lipid level
<200mg/dL
LDL cholesterol optimal blood lipid level
<100mg/dL
HDL cholesterol optimal blood lipid level
above 40mg/dL for men
above 50mg/dL for women
Cardioprotective: >60mg/dL
Triglyceride optimal blood lipid level
<150mg/dL
Antioxidant nutrients
Vitamin A, D, C
Selenium, Zinc
