4. Lipids Flashcards
(22 cards)
What are the common properties of lipids?
- Lipids do not readily dissolve in water
- Yield 9 kcal per gram
- Fats (solid) and oils (liquid)
Define triglyceride.
3 fatty acids bonded to glycerol.
What is a fatty acid?
Long chain of carbons bonded together.
Alpha end (carboxylic acid group - COOH)
Omega end (methyl group - CH3)
Functions:
- form body structures
- perform important functions for the immune and nervous system
- produce regulatory compounds
Define phospholipid.
- Glycerol + 2 fatty acids+ phosphorus-containing compound
- synthesized by the body as needed
- component of cell membrane
- play a role in digestion, absorption, and transport of lipids
Define sterols.
- multi-ringed structure
- cholesterol (found only in foods of animal origin)
- phytosterols (found in foods of plant origin)
Importance of essential fatty acid
When the essential fatty acids are consumed, the body can use them to make other, nonessential fatty acids. These eventually give rise to a variety of eicosanoids that regulate body functions.
Describe a Cis fatty acid.
The hydrogens that flank the carbon-carbon double bond lie on the same side.
Describe a Trans fatty acid.
The hydrogens that flank on a double bond lie on opposite sides of the double bond.
What are some food sources of essential fatty acids?
- Safflower oil
- Sunflower oil
- Nuts and seeds
- Chicken
- Flaxseeds
- Walnuts
- Chia seel oil
What are some food sources of phospholipids?
- Wheat germ
- Peanuts
- Egg yolk
- Soybeans
- Organ meats
What are some food sources of sterols?
- Eggs
- Meats
- Whole milk
What are some food courses of saturated fatty acids?
- Coconut oil
- Butter
- Palm oil
- Lard or beef fat
What are some food sources of monounsaturated fatty acids?
- Olive oil
- Canola oil
- Peanut oil
What are some food sources of polyunsaturated fatty acids?
- Safflower oil
- Sunflower oil
- Corn oil
- Soybean oil
What are the 4 lipoproteins?
- Chylomicron
- Very-low density lipoprotein (VLDL)
- Low-density lipoprotein (LDL)
- High-density lipoprotein (HDL)
What is the main function of chylomicrons?
Primary component: triglyceride
Function: carries dietary fat from the small intestine to cells
What is the primary function of VLDL?
Primary component: triglyceride
Function: carries lipids made and taken up by liver to cells
What is the primary function of LDL?
“bad cholesterol”
Primary component: cholesterol
Function: carries cholesterol made by the liver and from other sources to cells
What is the primary function of HDL?
“good cholesterol”
Primary component: protein
Function: contributes to cholesterol removal from cells and, in turn excretion of it from the body
Describe the functions of the various forms of lipids in the body.
- Provide energy
- Structural components
- Regulate cellular processes
What are the current recommendations for fat intake?
Total fat: no RDA for total fat intake for adults
Acceptable macronutrient distribution range:
- 20-35% for kcal from fat
- 44-78 grams for 2000 kcal
What are double bonded and on the long chain of the bond
Omega 3 and Omega 6 fatty acids
