Lipids - Nutrition Ch 5

lipid kcals

9 calories

AMDR for lipids

20-35%

limit cholesterol intake to…

less than 300 mg

ideal ratio of omega 6 to omega 3

6:1

what type of lipid is better for infants?

shorter chains, more liquid and water soluble

a short chain of fatty acid is _______

more liquid

a long chain of fatty acid is more _______

more solid

saturated bond

single bonds, solid at room temp

unsaturated bond

double bonds, more liquid

energy source in lipids

carbon

cis fat

occurs naturally, bent chain

trans fat

more saturated, straight chain

why are trans fats bad?

they raise LDL and lower HDL levels

what causes a lipid to be non-essential?

the double bond is past the 9th carbon

examples of essential lipids

omega 3, omega 6, eicosanoids

triglycerides

most abundant lipid, stored in adipose, fats & oils in food

phospholipids

2% of dietary lipids, body can make, fat & water soluble

sterols

small percentage, ex. cholesterol

what is a triglyceride made up of?

glycerol and 3 fatty acid tails

main role of triglycereides

energy source (60% of body’s resting energy)

what type of fat are omega-6 and omega-3?

triglycerides

fat-soluble vitamins

ADEK

omega-3 foods

fish, soy oil, canola oil, walnuts, flaxseed oil

omega-6 foods

seeds, nuts, corn & veggie oil, meats, poultry, eggs

another role of triglycerides

to insulate and protect

what are phospholipids made up of?

glycerol + 2 fatty acids + phosphate group

roles of phospholipids

emulsify food, form cell membrane, coat lipoproteins

phospolipid foods

egg yolks, liver, soybeans, peanuts

what is the structure of a sterol, how is it different?

multiple rings, no glycerol backbone or fatty acid which body uses for energy

mg of cholesterol made in the liver

1000 mg/day

cholesterol uses

structural components of cell membranes, precursor to other substances, bile

phytosterols

reduce intestinal absorption, lower cholesterol

cholesterol foods

only in animal foods

lingual phase

first phase of lipid digestion

lipid enters the bloodstream…

1-2 hours after leaving stomach

fat levels peak after…

3-4 hours

fat clears the body after…

10 hours

how much dietary cholesterol is absorbed?

50%

what allows lipids to enter the bloodstream?

lipoprotein carriers

enterohepatic circulation

bile salts recycle through intestines and liver

chylomicron

90% triglyceride

VLDL

66% triglyceride

IDL

40% triglyceride

LDL

6% triglyceride, 50% cholesterol

HDL

5% triglyceride, 20% cholesterol, +50% protein

HDL job

picks up cholesterol in bloodstream

lipoproteins

chylomicron, VLDL, LDL, IDL, HDL

olestra

fat replacer

atherosclerosis

risk from high blood cholesterol

three stages of cancer

initiation, promotion, progression

signs of metabolic syndrome

abdominal fat, high BG, high triglyceride, low HDL, high BP