Nutrition Exam 2 Chapter 5 Lipids

What are fatty acids?

Carbon chains with hydrogens attached. Acid group (COOH) on one end and a methyl group (CH3) on the other end. Even number of carbons Length of chain Short-chain fatty acids have 2 to 4 carbons. Medium-chain fatty acids have 6 to 12 carbons. Long-chain fatty acids have 14 to 24 carbons. Saturated or Unsaturated

What are the sterol food sources?

Cholesterol—animal sources − Plant sterols—interfere with cholesterol absorption

What benefits do regular consumption of omega-3 provide?

-Help prevent blood clots, protect against irregular heartbeats, improve blood lipids, and lower blood pressure. − Supports a healthy immune system and suppresses inflammation.

What does the AHA recommend in terms of fish intake and why?

AHA recommends eating at least two servings of fish per week due to EPA and DHA content.

Trans-fatty acid

has hydrogens on the opposite sides of the double bond. More solid at room temperature than cis • The trans form typically occurs in partially hydrogenated foods.

Cis-fatty acid

has hydrogens on the same side of the double bond. • Most naturally occurring unsaturated fatty acids in foods are cis.

What did the FDA ban in 2015? And why?

partially hydrogenated oils from use in foods. − Raise LDL levels and lower HDL levels; increase the risk of heart disease (Trans fats)

Micelles are

tiny spherical complexes of emulsified fat that arise during digestion; most contain bile salts and the products of lipid digestion, including fatty acids, monoglycerides, and cholesterol

What is a monounsaturated fatty acid?

1 double bond

What is the composition of a triglyceride

1 glycerol and 3 fatty acids

How does the following lipids effect LDL and HDL levels? And what is the main goal?

1. Saturated fats- increase LDL cholesterol and HDL levels , promote blood clotting 2. Trans fats- increase LDL cholesterol (heart disease) reduces HDL levels 3. Monounsaturated fats- lower LDL without reducing HDL 4. Polyunsaturated fats -lower LDL levels and may lower HDL levels. (Considered healthful) 5. Dietary Cholesterol- less of an effect on blood cholesterol than saturated fat. The goal is to reduce intake of Saturated and Trans fats and replace them with Unsaturated fats.

Explain the process of lipid digestion

1.) In the small intestine:, bile emulsifies fat, 2.) bile is absorbed into the blood OR in the colon, bile that has been trapped by soluble fibers is excreted in feces 3.) after bile is reabsorbed- In the Liver, bile is made from cholesterol 4.) in the gallbladder, bile is stored

Where are phospholipids soluble?

Fat and water

Which of the following are absorbed directly into the bloodstream?

Glycerol and short- and medium-chain fatty acids All three of these are small enough to easily cross into intestinal cells and then enter the bloodstream.

What is the compositions of phospholipids?

Glycerol with two fatty acids and a group that contains phosphorus.

What diffuse into the absorptive cells of the villi. Enter into the capillary network (bloodstream)

Glycerol, short- and medium-chain fatty acids

What lipid protein is considered "good cholesterol" and what is considered "bad cholesterol"

Good- HDL, carries lipids away from tissues and doesn't contribute to plaque build up Bad- LDL conveys lipid to tissue, high levels

What are the other uses of fat in the body?

Skin insulation Shock absorption Cell membrane material Cell signaling pathways

Foods that contain mostly saturated fats are in which state at room temperature?

Solids

What characteristic allows phospholipids to be useful as emulsifiers and as part of the cell membrane?

The hydrophilic heads and hydrophobic tails

What clears the remnants of Chylomicrons from the blood stream to synthesize new lipids and other lipoproteins?

The liver

What are triglycerides? And what is the AMDR recommendation for them

The stored form of fat 20-35%

What makes of 95% of fats

Triglycerides

What is the difference between a saturated fatty acid and an unsaturated fatty acid?

a saturated fatty acid has only c-c bonds and no double bonds an unsaturated fatty acid has at least 1 c=c bond

Where is fat stored in the body?

adipose tissue -secretes hormones -Reduced or excessive body fat change adipokine secretions

What are lipoproteins?

are water-soluble structures that transport lipids through the bloodstream.

What are eicosanoids?

biologically active lipids with local hormone-like activity Essential for : normal growth, visual acuity, and cognitive development, prevention of heart disease.

Cholesterol and the reassembled triglycerides are coated with a thin layer of protein, phospholipids, and cholesterol to form_____. Where are these released to?

chylomicrons Lymphatic system

What is biles role in the digestion of fat?

emulsifies fat

What is a polyunsaturated fatty acid?

fatty acid with two or more double bonds

What are the end products of lipid digestion?

glycerol, fatty acids, monoglycerides, cholesterol, an phospholipid fragments

Saturated fatty acid SFA

is a fatty acid that has each carbon atom within the chain filled with hydrogen atoms.

Unsaturated fatty acid

is a fatty acid that is missing hydrogen atoms and has one or more double bonds within the carbon chain.

What is the recommendation for saturated fat intake

less than 10% of total calories

Where is bile made and stored?

made in the liver and stored in the gallbladder

Where do trans fats occur?

small amounts naturally in whole milk products, butter, and meat.

Where does lipid digestion occur?

small intestine

During lipid digestion what happens after absorption?

the fragments are reassembled into triglycerides and phospholipids.

During lipid digestion what happens when fat enters the small intestine?

the gallbladder releases its stores of bile.

Know how to calculate reccomendations based on calorie intake

————

What are the health effects of replacing saturated fats with unsaturated fats?

• Reduces LDL cholesterol • Lowers risk of heart disease and related deaths • Protects against some cancers

What factors raise HDL and lower LDL

− Unsaturated fat intake over saturated fat − Soluble Dietary Fiber − Phytochemicals − Low alcohol consumption − Physical activity

What is the AMDR for fat?

20-35% of total calories

What types of foods are high in saturated fats?

(Animal products) bacon, milk, butter, cheese, shortening, coconut oil)

What types of foods are high in unsaturated fats?

(Plant-based) salmon, vegetable oil, pecans, avocado, peanut butter

What are good sources of omega 3?

Fish, eggs, soy bean oil, canola oil, flax seed, walnuts, fortified dairy/soy

Where does fat digestion occur?

GI tract ??????

What to dietary guidelines reccomnd for trans fat intake

Keeping it as low as possible

What plays a role in the development of atherosclerosis?

Lipoproteins

Foods that contain mostly polyunsaturated fats are in which state at room temp?

Liquid

What roles to sterols play in the body?

Made in the body Bile acids, sex hormones (testosterone or estrogen, adrenal hormones (cortisol, cortisone), vitamin D, and cholesterol. From CHOLESTEROL

What risks are higher for someone who takes excessive doses of omega-3?

May lengthen bleeding time, interfere with wound healing, raise LDL cholesterol, & suppress immune function

Which fatty acids are essential?

Must be supplied by the diet Linoleic acid (Omega-6) Alpha Linolenic acid (Omega-3)

Is there a limit to how much fat can be stored in the body?

No, they Provide the cells with energy Virtually unlimited ability to store fat energy

What are the roles of the phospholipids

Part of cell membrane and emulsifiers

Long-chain fatty acids, bile, cholesterol, and fat-soluble vitamins pack together in________. When ________come close to villi, their contents diffuse into absorptive cells.

micelles

Explain the process of lipid absorption

?????

What is the difference between cis-fatty acids and trans-fatty acids?

Cis- and trans- refer to the configuration of hydrogens around the double bond. Trans-fatty acids have hydrogens on opposite sides of the double bond. Cis-fatty acids have both hydrogens on the same side of the double bond (Hint: remember cis- and "same").

Chylomicrons

Contain the highest amount of triglyceride and are therefore the least dense thin layer of protein, phospholipids, and cholesterol released in lymphatic system

What are phospholipids referred to as in the food industry?

Emulsifiers

Dietary guides for American recommends replacing starred and trans fats with what?

Unsaturated fats

What are the different types of lipids and their functions?

Very-low-density lipoprotein (VLDL) Made in the liver then shrink in the bloodstream as cells take up triglycerides Low-density lipoprotein (LDL) Higher in cholesterol, lower in triglycerides; taken up by cells after binding to receptors High-density lipoprotein (HDL) Carry cholesterol back to the liver for recycling or excretion

What are eicosanoids made from?

omega-3 and omega-6 fatty acids Hormonelike", but only affect the cell in which they are made or near and may exert different effects on different cells. Omega-3 eicosanoids exert an anti-inflammatory effect, lower blood pressure, prevent blood clot formation. Omega-6 eicosanoids promote blood clot formation and inflammation ©2022 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.