Lipids 2.3 Flashcards
types of lipids
triglycerides, phospholipids and cholesterol
how many kcal per gram is fats and oils
9 kcal per gram
simplest form of lipids
fatty acids
structure of fatty acids
alpha end (acid) and omega end (methyl)
saturated fats at room temperature
solid
unsaturated fats at room temperature
liquid
type of fatty acids in foods of animal origin
saturated
type of fatty acids in foods of plant origin
unsaturated
triglyceride structure
three fatty acids bonded to glycerol
in saturated fats what are the carbon saturated with
hydrogen
where is the double bond on omega 3
the third carbon from the omega end
where is the double bond on omega 6
the sixth carbon from the omega end
cis fatty acids
bond ends point in same direction in relation to the double bond
trans fatty acids
ends are pointing in different direction of the bond giving us a different chemical structure and function
how many fatty aids must be supplied by the diet to maintain health
two fatty acids (omega 3 and 6)
how does omega 3 fatty acids affect health
decrease blood clotting, decrease triglycerides, decrease inflammation
how does omega 6 fatty acids affect health
regulates blood pressure, increase blood clotting, regulated inflammatory response (more may promote inflammation)
signs and symptoms of essential fatty acid deficiency
flaky, itchy skin, diarrhea, increased risk of infection, stunted growth and reduced wound healing
how are phospholipids synthesized
as the body needs it
structure of phospholipids
glycerol and 2 fatty acids and a phosphorus containing compound
structure of sterols
5-6 sided ring
what form do we find sterols in most often
cholesterol in foods of animal origin and phytosterols in foods of plant origin
protein fat layout
plant protein is low in fat, animal protein higher fat, nuts are high in fat
dairy fat layout
skim milk is low, whole milk is medium, ice cream is high
grains fat layout
generally low in fat but tend to add fat when we are preparing them
fruit and veggies fat layout
most low in fat, exception is avocado
alpha linolenic acid
omega 3 fatty acids
linoleic acid
omega 6 fatty acids
what is the dietary guideline of servings of fatty fish per week from the AHA
2 servings
are phospholipids essential
no because our body makes them but they are widespread in foods
what does lecithin do
it is added to foods as en emulsified to keep liquid and water mixtures from separating
how is fat substituted
as a fatty acid bound to sucrose
fat rancidity
limits shelf life, oils decompose from breakdown of double bonds in unsaturated fatty acids by UV light or oxygen, produce unpleasant odor and flavor
how to prevent rancidity
addition of antioxidants, hydrogenation
what is the hydrogenation of fatty acids
adding hydrogen to double bonds to solidify an oil and add shelf life
are hydrogenated fats bad
yes
is coconut oil bad for - if so why
yes, almost 90% of fatty acids are saturated
digestion of triglycerides in the mouth
mechanical digestion via lingual (salivary) lipase
digestion of triglycerides in the stomach
lingual lipase still going and using gastric lipase
digestion of triglycerides in the small intestine
duodenum releases CCK, bile emulsifies fats, pancreatic lipase
end products of the digestion of triglycerides
monoglycerides and fatty acids
digestion of phospholipids in small intestine
phospholipase from pancreas and intestinal cells
end products of digestion of phospholipids
glycerol, fatty acids and phosphorus contains parts
digestion of cholesterol in small intestine
cholesterol esterase from pancreas
end products of digestion of cholesterol
cholesterol and free fatty acids
what percent of dietary fat is absorbed
95%
where are short and medium chain fatty acids absorbed into
hepatic portal vein
where are long chain fatty acids absorbed into
lymphatic system
lipoprotein
transport vehicle for lipids in the blood, cholesterol needs a transport
types of lipoprotein
chylomicron, VLDL, LDL, HDL
chylomicron role and primary component
carries dietary fat from small intestine to cells - triglyceride
VLDL role and primary component
carries lipids then taken up by liver to cells - triglycerides
LDL role and primary component
carries cholesterol from liver and other sources to cells - cholesterol
HDL role and primary component
helps remove cholesterol from cells and excretes it from body - protein
how are chylomicrons transported throughout the body
eat dietary fat - packaged as chylomicrons - absorbed through lymphatic system - released into blood - circulated around body - cells can take these up and take in the fatty acid and triglycerides - eventually ends back at liver
which lipoprotein is the biggest and has the highest density
chylomicron
what is LDL known as
bad cholesterol
where is LDL from
liver
primary risk of high LDL
promotes atherosclerosis and increased risk of cardiovascular disease
what is HDL known as
good cholesterol
where is HDL from
liver and small intestine
benefits of high HDL
block oxidation of LDL, reduce formation of plaque, reduce risk of cardiovascular disease
functions of triglycerides
yield energy, store energy, insulate and cushion body, transport fat soluble vitamins, regulate body processes
functions of phospholipids
emulsifier, cell membrane structure, digestion of lipids, transport lipids
functions of cholesterol
formation of hormones, structural component of ell membrane and lipoproteins, synthesis of bile acids (fat digestion)
RDA for Toal fat
none
acceptable macronutrient distribution range of kcal from fat percentage
20 to 35 %
acceptable macronutrient distribution range of kcal from fat in grams
44 to 78 of 2000 kcal
dietary guidelines limit saturated fat to what percentage of total calories
10%
typical saturated fat intake
11% of total calories
where is the first place you would see a deficiency in essential fatty acids
skin
dietary guidelines for limits on dietary cholesterol
none
does dietary cholesterol have an effect on blood cholesterol
very little
what happens if you have excessive omega 3
bleeding and hemorrhagic stroke
how does cardiovascular disease develop
plaque increase in size and stiffens, blood vessels become narrow and inflexible
non controllable risk factors for cardiovascular disease
men over 45 years, women over 55 years, males, hereditary
controllable risks for cardiovascular disease
smoking, high blood pressure, high cholesterol, inactivity, excess body fat, diabetes
medications to lower LDL cholesterol
statins, resins, absorption inhibitors
medications to raise HDL cholesterol
niacin
medications to lower blood triglycerides
fibrates
two surgical treatments for cardiovascular disease
percutaneous transluminal coronary angioplasty and coronary artery bypass graft
how is majority of energy stored in the body
fatty acids then converted to ATP by muscle cells
does fat provide more energy than carbs
yes 2x
what does the ability of muscles to use fat depend on
intensity of exercise
does the body burn fat at higher or lower intensity exercise
lower
