module 3: high fat, low fat, no fat

lipids include what??

• phospholipids

• sterols

• triglycerides

oil and butter are made up out of what?

made up of triglycerides with different types of fatty acids

phospholipid

• hydrophobic tail and hydrophilic head, which are soluble in fat and water, respectively

lethicin

• delivers nutrients to the body, such as choline, glycerol and fatty acids, but it plays an important role in the kitchen as an emulsifier: allows you to mix fat and water

• The lecithin in eggs acts as an emulsifier in foods

lecithin in soybeans

• may help to decrease cardiovascular disease risk by inhibiting cholesterol absorption from food, and promoting cholesterol excretion from the body

what are sterols??

• Sterols are another type of lipid that we get from our diet

• cholesterol is the type of sterol found in animal products

cholesterol

• most sterols our bodies make on their own (endogenously) 

• we need cholesterol to make sex hormones 

• approx. 40 - 60% of cholesterol found in our foods is absorbed 

plant products

• contain plant sterols known as phytosterols

how can plant sterols and stanols can lower cholesterol levels??

• by competing with dietary cholesterol absorption,

• now these compounds have been added to food products such as margarine

• contain about 2 grams of plant sterols or stanols in a 25 gram serving

• reduces the absorption of cholesterol by about 50%

• At doses above 2 grams of plant sterols or stanols per day, there is no further reduction in cholesterol levels

how do we get vitamins

• We get vitamin D₂ from some plant sources

• vitamin D₃ mostly comes from synthesis in the skin after exposure to ultraviolet B rays in sunlight

• D₃ naturally from only a few foods, including the skin of fatty fish (for example, salmon), some liver oils, and eggs from chickens supplemented with vitamin D

Triglycerides, or triacylglycerol (TAG)  molecules

• the most abundant type of lipid in our diet

• triglycerides are made up of a glycerol molecule and 3 fatty acid molecules

• Fatty acids are chains of 4-24 carbons

unsaturated fatty acids

• double bonds between carbons

• unsaturated fats are liquid at room temperature

saturated fatty acids

• single bonds between carbons

• saturated fats are more solid at room temperature

monounsaturated fats

triglycerides that are composed of fatty acids with 1 double bond

polyunsaturated fats

triglycerides that are composed of fatty acids with more than 1 double bond

saturated fats

saturated fats are made of triglycerides with no double bonds

Coconut oil

saturated fat

butter

saturated fat

palm oil

saturated fat

olive oil

monounsaturated fat

Canola oil

monounsaturated fats

Saturated fatty acid (SFA) 

Lauric acid (12:0)

Palmitic acid (16:0)

Stearic acid (18:0)

no more than 10% daily kcal

Monounsaturated fatty acid (MUFA)

Oleic acid (18:1)

Polyunsaturated fatty acid (PUFA)

Linoleic acid (18:2)

Arachidonic acid (20:4)

Alpha-linolenic acid (18:3)

Eicosapentaenoic acid (20:5) (EPA)

Docosahexaenoic acid (22:6) (DHA)

omega-3 and omega-6

trans fatty acid

• these fatty acids have no known health benefit,

• the intake of trans fats is associated with an increase in LDL (BAD) cholesterol levels and chronic diseases, such as cardiovascular disease

• no more than 1% per day

essential fatty acids

we have to get the, from our diet we cant produce them

small intestine is important for what in digestion

the absorption of fat

the tongue produces lingual lipase which does what

breaks down triglycerides into monoglycerides, fatty acids and glycerol

After fatty acids and glycerol molecules have been absorbed, they are carried by _______ through the ________.

chylomicrons, lymphatic vessels

The liver makes bile from cholesterol, and bile is stored and released by the gallbladder. Glycerol and short (4-6 carbons) and medium (8-12 carbons) chain fatty acids are not incorporated into chylomicrons, like long (more than 14 carbons) chain fatty acids are, and therefore they enter the blood stream faster

Short chain fatty acids

• 4-6 carbons

• Butter (contains butyric acid, 4 carbons) 

Medium chain fatty acids

• 8-12 carbons

• Coconut oil (contains lauric acid, 12 carbons)

Long chain fatty acids

• 14 or more carbons

• Olive oil (contains mostly oleic acid, 18 carbons)

• Fish oil (contains mostly omega-3 fatty acids, 20 or 22 carbons) 

who consumed more calories from saturated fat had a greater risk of what??

coronary death

• replacing energy (kcal) from carbohydrate with energy from saturated fatty acids increased the risk of death by around 10%,

• replacing carbohydrates with energy from trans fatty acids increased the risk of death by around 20%

what’s the recommended intake from saturated fats

10% of daily kcal intake 

whats the recommended intake from trans fatty

no more than 1% intake

it is recommended that how much kcal intake come from omega-6 polyunsaturated fatty acids

5-10% of daily kcal comefrom omerga 6

how much is recommended from omega 3 polyunsaturated fatty acids.

0.6-1.2% of daily kcal come from omega-3