Lipids Flashcards
Three classes of lipids
triglycerides, phospholipids, sterols
what is fats role in the body?
energy stores, muscle fuel, emergency reserve of fuel, padding, insulation, membranes, raw materials to convert
What is fats role in foods?
nutrient, energy source, raw material, sensory appeal, increases satiety, gives desirable texture
Fatty acids structure:
carbohydrate chain with a methyl group on one end and a carboxylic group on the other
___ C is a long chain, ___ is a medium chain, ___ is a short chain
12-24/6-10/<6
Coconut oil: mostly ___ acid, high in ___ chain f.a., behaves somewhere between a vegetable oil and an animal fat
Lauric/medium
phospholipid structure:
phosphate group+glycerol+2 f.a.
sterol structure
C rings with side chains that differentiate them
sterols are made in the ___
liver
Cholesterol: only in ___ products, made by the ___, used to make ___ acids, ___, vitamin ___, as a ___ component in cells, inhibited by ___
animal/liver
bile/hromones/D/structural
plant sterols
Essential f.a.:
linoleic (___:___ n-___)
linolenic (___:___ n-___)
18/2/6
18/3/3
eicosanoids:
n-6 family: increase blood clotting, platelet aggregation, blood pressure, and risk of CVD
n-3 family: decrease all these things
n-6 and n-3 eicosanoids should be consumed in ___
balance
Omega-3 f.a.
RDA:
sources:
1g/day
fish and fish oils
Lipoproteins: ___ interior with ___, surrounded by ___, PRO covers the structure. ___ exterior allows them to travel through blood stream
triglyceride/cholesterol/phospholipids
Hydrophilic
sizes of lipoproteins:
chylomicrons>VLDL>LDL>HDL
HDL
formed by liver cells, pick up cholesterol from body cells and deliver it to the liver to excrete
VLDL
formed by the liver, deliver lipids to body cells and eventually become LDL
LDL
formed by VLDL with lipids removed, delivers lipids to body cells r returns to liver
chylomicrons
formed by intestinal cells using dietary lipids, deliver dietary lipids to cells and eventually become remnants which are removed by the liver
Fat cell structure and growth
contain a large central globule of pure fats, new triglycerides form droplets at the periphery of the cell and eventually merge with the inner globule which grows, cell membrane expands along with the central globule
Fed state
increased insulin, chylomicrons, fat synthesis, lipogenesis VLDL
Fasted state
decreased insulin, glucagon, increased hormone sensitivity
Atherosclerosis
intercellular lipids and foam cells build in a fatty streak, fibrous plaque begins to form, it calcifies eventually and forms lesions, cause rough, rigid arteries with a narrow lumen
How to decrease CVD
- unsaturated fats>saturated fats
- n-3 f.a.>n-6 f.a.
- lose weight
- exercise
- moderate alcohol consumption
- increase dietary soluble fibre
- choose low glycemic index foods
- eat plant sterols
- drug options
DRI:
UL:
no AI
no UL
