Chapter 5 Flashcards
Identify the three types of lipids.
Triglycerides
Phospholipids
Sterols
Identify the three types of lipids.
Triglycerides
Phospholipids
Sterols
What is the structure of a triglyceride? How are they classified?
Three fatty acid molecules
Fatty acids are long chains of carbon atoms surrounded by hydrogen atoms
One glycerol molecule
Glycerol is a 3-carbon alcohol that is the backbone of a triglyceride
What is the most common food-based lipid?
Triglycerides
Sources of Monounsaturated fat?
Olive oil, Canola oil, and cashew nuts
Sources of Polyunsaturated fatty acids?
Cotton seed, canola, corn, and safflower oil
Where are sat fats found in foods? Why should they be limited in the diet and how much should we eat?
Saturated Fat less than 7-10% of our total energy.
Found in animal products,
Can raise cholesterol, cardiovascular disease, cancer,
What are trans fats? Where are these found in foods?
found in processed foods, and in fried foods.
How does absorption of fat differ based on the chain length of the fatty
acid?
Short- and medium-chain fatty acids are absorbed more quickly since they are not arranged into chylomicrons.
Triglycerides in the chylomicrons must be disassembled by lipoprotein lipase (LPL) before they can enter body cells.
After entering body cells, triglycerides can be:
Used immediately for energy Used to make lipid-containing compounds Stored in muscle or adipose tissue for later use
Understand the function of the following in digestion of fat: gallbladder,
liver, pancreas, bile, small intestine, Pancreatic enzymes.
Fats are not digested and absorbed easily because they are insoluble in water.
Little digestion of fats occurs in the watery environments of the mouth or stomach.
As fat enters the small intestine:
Bile is secreted from the gallbladder into the small intestine
Bile is produced by the liver and stored in the gallbladder
Bile disperses fat into smaller fat droplets (like soap)
Pancreatic enzymes break fat into 2 separate fatty acids and a monoglyceride
Micelles trap the free fatty acids and monoglycerides and transport them to the mucosal cells for absorption.
Fatty acids are reformulated back into triglycerides and packaged into lipoproteins for transport to the lymphatic system and blood.
What is emulsification? What is secreted into the GI tract for this to occur?
Bile
Briefly describe each of the reasons why we need fats in our diets.
Energy
Fat is very energy dense, containing 9 kcal per gram. 30-70% of the energy used during rest comes from fat. Fat is used for energy during exercise, especially after glycogen is depleted. Fat is also used as a way to store extra energy in the body for later use.
Fat is essential to many body functions
Part of cell membrane structure Facilitates nerve cell transmissions Protection of internal organs Insulation to retain body heat
What is the AMDR for total fat?
The Acceptable Macronutrient Distribution Range (AMDR) for total fat: 20-35% of calories should be from fat
Athletes and highly active people may need more energy from carbohydrates and can reduce their fat intake to 20-25% of total calories.
The AMDR for essential fatty acids:
5-10% of calories from linoleic acid (11 to 17 grams per day based on gender) 0.6-1.2% of calories from alpha-linolenic acid (1.1 to 1.6 grams per day based on gender)
What are the dietary recommendations for cholesterol, sat, and trans fats?
Cholesterol-less than 300 mg
Saturated Fat-Less than 7-10% of total energy
Trans Fat- 0
What is the structure of a triglyceride? How are they classified?
Three fatty acid molecules
Fatty acids are long chains of carbon atoms surrounded by hydrogen atoms
One glycerol molecule
Glycerol is a 3-carbon alcohol that is the backbone of a triglyceride
What is the most common food-based lipid?
Triglycerides
Sources of Monounsaturated fat?
Olive oil, Canola oil, and cashew nuts
Sources of Polyunsaturated fatty acids?
Cotton seed, canola, corn, and safflower oil
Where are sat fats found in foods? Why should they be limited in the diet and how much should we eat?
Saturated Fat less than 7-10% of our total energy.
Found in animal products,
Can raise cholesterol, cardiovascular disease, cancer,
What are trans fats? Where are these found in foods?
found in processed foods, and in fried foods.
How does absorption of fat differ based on the chain length of the fatty
acid?
Short- and medium-chain fatty acids are absorbed more quickly since they are not arranged into chylomicrons.
Triglycerides in the chylomicrons must be disassembled by lipoprotein lipase (LPL) before they can enter body cells.
After entering body cells, triglycerides can be:
Used immediately for energy Used to make lipid-containing compounds Stored in muscle or adipose tissue for later use
Understand the function of the following in digestion of fat: gallbladder,
liver, pancreas, bile, small intestine, Pancreatic enzymes.
Fats are not digested and absorbed easily because they are insoluble in water.
Little digestion of fats occurs in the watery environments of the mouth or stomach.
As fat enters the small intestine:
Bile is secreted from the gallbladder into the small intestine
Bile is produced by the liver and stored in the gallbladder
Bile disperses fat into smaller fat droplets (like soap)
Pancreatic enzymes break fat into 2 separate fatty acids and a monoglyceride
Micelles trap the free fatty acids and monoglycerides and transport them to the mucosal cells for absorption.
Fatty acids are reformulated back into triglycerides and packaged into lipoproteins for transport to the lymphatic system and blood.
What is emulsification? What is secreted into the GI tract for this to occur?
Bile
Briefly describe each of the reasons why we need fats in our diets.
Energy
Fat is very energy dense, containing 9 kcal per gram. 30-70% of the energy used during rest comes from fat. Fat is used for energy during exercise, especially after glycogen is depleted. Fat is also used as a way to store extra energy in the body for later use.
Fat is essential to many body functions
Part of cell membrane structure Facilitates nerve cell transmissions Protection of internal organs Insulation to retain body heat
What is the AMDR for total fat?
The Acceptable Macronutrient Distribution Range (AMDR) for total fat: 20-35% of calories should be from fat
Athletes and highly active people may need more energy from carbohydrates and can reduce their fat intake to 20-25% of total calories.
The AMDR for essential fatty acids:
5-10% of calories from linoleic acid (11 to 17 grams per day based on gender) 0.6-1.2% of calories from alpha-linolenic acid (1.1 to 1.6 grams per day based on gender)
What are the dietary recommendations for cholesterol, sat, and trans fats?
Cholesterol-less than 300 mg
Saturated Fat-Less than 7-10% of total energy
Trans Fat- 0
What would you look for in the ingredients list on a food label if you
were looking for trans fatty acids?
Partially hydrogenated oils
What food groups contain cholesterol?
Animal products
What is considered to be a healthy blood cholesterol level?
Desirable level that puts you at lower risk for coronary heart disease. A cholesterol level of 200 mg/dL or higher raises your risk.
Does the human body synthesize cholesterol?
yes
What lipid is both water and fat soluble and what is its purpose?
Fatty Acids
What are the 2 essential fatty acids?
Where are these found in foods?
Only two fatty acids are known to be essential for humans: alpha-linolenic acid (an omega-3 fatty acid) and linoleic acid (an omega-6 fatty acid).
Some of the food sources of ω-3 and ω-6 fatty acids are fish and shellfish, flaxseed (linseed), hemp seed, soya oil, canola (rapeseed) oil, chia seeds, pumpkin seeds, sunflower seeds, leafy vegetables, and walnuts.
Which type(s) of dietary fat is/are known to elevate blood cholesterol levels?
Dietary fats that are bad for the health are Saturated fat and Trans fat.
Identify the major risk factors that contribute to an increased risk for
cardiovascular disease
Overweight, Physical Inactivity, Smoking, Diabetes, Inflamation, Abnormal blood lipids LDL/HDL
What are the various types of lipoproteins
high-density (HDL)-Good
low-density (LDL) lipoproteins - Bad
HDL and LDL
Which are made by the gut? By the liver?
HDL is made by the liver
LDL is made in the gut
