Chapter 6: Fats Flashcards
Why are lipids needed in the diet? Name some of the most significant roles they play.
Fats are also called lipids.
They are a dense macromolecule and have high yields of energy they give the body through the beta-oxidation pathway. They differ greatly from the other macromolecules in both their digestion and assimilation.
- two types: essential and nonessential fats, similar to the protein. And they are similar to carbs in that there are different structural fats with varying roles in the body.
Some of the major roles for lipids are:
- They store and help use the fat-soluble vitamins which are A, D, E, and K.
- They maintain the function and integrity of cellular membranes.
- They provide a concentrated source of energy.
- They make meals more palatable and filling.
What are the significant lipids that are found in our diet?
The major lipids of the human diet and body are:
a. Triglycerides
b. Fatty acids
c. Essential fatty acids
d. Omega-3 fatty acids
e. Gamma-linolenic acid
f. Medium chain triglycerides
g. Phospholipids
h. Lecithin
i. Cholesterol
What classifications exist for these fatty acids in the body?
We classify fats based on the number of carbons in their chains:
- Short-chain fatty acids have 4 – 5 carbon atoms.
- Medium-chain fatty acids have 6 – 12 carbon atoms.
- Long-chain fatty acids have 19 – 23 carbon atoms.
- Anything with 20 or more carbons is considered to be a long-chain fatty acid.
We also classify fats as either saturated or unsaturated. Saturated fats are fats or fatty acids that have single bonds between the carbons. Unsaturated fats are fats or fatty acids that have one or more double bonds between the carbons.
Know the essential fatty acids and the specific functions they do. Emphasize the omega-3 and omega-6 fatty acids.
We have 2 truly essential fatty acids and then 3 others that are very important, but not fully essential. We can refer to these other fatty acids as conditionally essential. These essential fatty acids are considered to be essential due to the fact that they cannot be made in the body. So, to get them in the body, we must use supplements or eat them as part of a balanced diet.
Omega-3 and Omega-6 are the two absolutely essential fatty acids that we need. Omega- 3 fats are going to play a vital role in human cell membranes on a microlevel. On the macro side, we see these playing a role in brain development, fighting inflammation, improving bone density, and reducing liver fat. Omega-6 fats are eaten in greater levels than the omega-3 fatty acids. Linoleic acid is an omega-6 fatty acid that has a vital role in cell membrane fluidity and structure, and it also works as part of cell signaling. Alpha- linolenic acid is an omega-3 fatty acid, and it works in areas like growth or as a precursor for two other important fatty acids. These two fatty acids are EPA and DHA. They are both omega-3 fatty acids and they can be produced in the body from another omega-3. They are used for dispersing cholesterol in the bloodstream. Last, we have Gamma Linolenic Acid. This is used for many bodily functions.
What do phospholipids primarily do for the body? Where are they found?
Phospholipids are different from regular triglycerides in the fact that they have two fatty acid groups and one phosphate group attached to a glycerol. The glycerol is going to be attracted to water, this is called being hydrophilic, and the fatty acid tails are repelled by water, which is known as hydrophobic. The phospholipids are major structural lipids in all organisms and important components in all living cells. The phospholipids are going to make up the cell membranes and the membranes of subcellular organelles.
Know the two different forms of cholesterol and which one should be avoided in the
typical American diet.
Cholesterol is a member of a group of lipids called sterols and are produced by the body. This comes from mostly animal products, but plants do have small amounts of it. Cholesterol is in all cells, it is a precursor for bile acids, a precursor for adrenal and sex hormones, a vitamin D precursor, and it has a large role in the brain and nervous system tissues. We have two types of cholesterol: LDL and HDL. HDL is considered to be the good cholesterol, and LDL is considered to be the bad form of cholesterol.
Break down the digestion of fats at each of the specific locations where the body acts on them.
The mouth starts the process of digestion by chewing the food and breaking it down into smaller pieces. Then, we have the addition of lingual lipase, which starts the breakdown of the molecules of fat. This breaks some of them down into partial glycerides and free fatty acids. Saliva is also an emulsifier that disperses tiny droplets of fat and separates them from watery components. In the stomach we have gastric lipase working to break down triglycerides into free fatty acids and diglycerides. Only around 30 percent of fats are broken down after 2 – 4 hours post-meal. Absorption into the bloodstream happens through four pathways. We have the exogenous, endogenous, reverse cholesterol transport, and ketogenesis.
What’s the difference bw EPA and DHA?
Eicosapentaenoic Acid (EPA) is an omega-3 fatty acid used to reduce tryglyceride levels.
Docosahexaenoic (DHA) is an omega-3 used to reduce chronic disease and functions in brain development and eyes.
what do triglycerides do?
Triglycerides are 3 fatty acid molecules linked to a glycerol molecule. They store unused calories and provide your body with energy
what does Cholesterol do?
Cholesterol is used to build cells and certain hormones.
what are the names of the omega-3 fatty acids?
Docosahexaenoic (DHA) Eicosapentaenoic Acid (EPA)
Alpha-Linolenic Acid (ALA)
What are good sources of omega-3 fatty acids?
flaxseed oil
walnuts
chia seeds
fatty fish
poulty
How many daily mg of cholesterol are recommended?
<300mg/day
what is linoleic acid?
A common essential omega-6 fatty acid.
what are omega-6 fatty acids?
A group of essential polyunsaturated fatty acids, including linoleic acid.
