Nutrition Chapter 5

Which type of cholesterol contributes to plaque formation?

Atherosclerosis.

How much energy to lipids contain (kcal/gm)?

9 kcal/gm

What is metabolic syndrome?

A cluster of biochemical and physiological abnormalities associated with the development of cardiovascular disease and type 2 diabetes.

What can be done to prevent the progression of of atherosclerosis?

A healthy diet, quit smoking and be physically active.

What are fatty acids?

A molecule made up of a chain of carbons, linked to hydrogens, with an acid group at one end of the chain.

What are micelles?

A particle that is formed in the small intestine when the products of fat digestion are surrounded by bile. It facilitates the absorption of lipids.

What is the function of lipoprotein lipase?

A particle that transports lipids in the blood.

What is hydrogenation?

A process whereby hydrogen atoms are added to the carbon- carbon double bonds if unsaturated fatty acids, making them more saturated.

What is a phospholipid?

A type of lipid whose structure includes a phosphorus atom.

How are phospholipids used in cooking?

Acts as emulsifiers: They stabilize salad dressing so it doesn't separate.

What is lecithin? Where is lecithin found?

- A phosphoglyceride composed of a glycerol backbone, two fatty acids, a phosphate group, and a molecule of choline; often sued as an emulsifier in foods. - The food industry used lecithin as an emulsifier in margarine, salad dressings, chocolate, frozen desserts, and baked goods to prevent oil from separating from the other ingredients.

Explain the function of lipids in cooking?

- Add texture to food - flaky pie crust. - Add tenderness to food - butter cookies crumble. - Add moisture to food - ice cream. - Add flavor to food - butter flavor in pound cake. - Form emulsion - lecithin in egg yolk forms a mayonnaise.

What are the different types of fat replacers?

- Carbohydrate-based dat substitutes (brownies, cakes & cookies) - Fat mimetic (Salatrim, Olestra) - Protein-based fat replacers (Egg whites or skim milk)

What are the functions of essential fatty acids?

- Cell membrane structure. - Important for skin integrity. - Needed for development and functioning of nervous system in infants and children. - Fertility. - Maintaining RBC structure. - Needed for production of Eicosanoids (chemicals int he body that have hormone functions)

How are chylomicrons, VLDL's and LDL's formed?

- Chylomicrons: The triglycerides combine with phospholipids, cholesterol, and fat soluble vitamins and coated with protein to form chylomicrons. -LDL: -VLDL:

What is the function of HDL, LDL, and chylomicrons in our body?

- Chylomicrons:Deliver triglycerides t0 liver, adipose and muscle tissue. -HDL: Primary carries of cholesterol in blood. -LDL: Associated with lower risk of heart disease.

What are dietary sources of EPA and DHA?

- EPA: Fish, fish oils, & marine sources. - DHA: Fish, fish oils & specialty eggs/dairy products.

What is the correct sequence for fat digestion and absorption?

- Fat digestion starts in the stomach where gastric lipase starts to breakdown TG's. - In the small intestine, bile salts emulsifies fat and breaks up into particles called micelles. - Pancreatic lipase breaks up micelle's down into glycerol and free fatty acids. - Glycerol (monoglycerides) and free fatty acids enter epithelial cells in intestinal wall. - Inside epithelial cells, fatty acids are resynthesizes into triglycerides. - The triglycerides combine with phospholipids, cholesterol and fat soluble vitamins and are coated with protein to form chylomicrons. - Chylomicrons carry lipids through intestinal wall through large veins in neck. - Chylomicrons circulate in blood and deliver triglycerides to cells in liver, adipose and muscle.

What happens when plaque breaks off in the coronary or carotid artery?

- If plaque breaks off int he coronary artery, a clot forms around there plaque. The clot blocks blood flow to the heart restricting oxygen and other nutrients, resulting in a heart attack. - If plaque breaks off or ruptures in the carotid artery, a clot can block blood flow to the heart resulting in a stroke.

What is LDL and HDL cholesterol?

- LDL Cholesterol: "Bad cholesterol" - carries cholesterol from liver to tissues. Can clog arteries and increase risk for heart attack and stroke levels under 100mg/dl are optimal. - HDL Cholesterol: "Good cholesterol" - carries cholesterol from tissue back to liver. Keeps LDL from clogging arteries. An HDL reading of 60mg/dl or more is linked with decreased risk of CVD.

What are the various functions of cholesterol in the body?

- Major part of the cell membrane. - Needed for production of hormones, estrogen, testosterone and cortisol. - Needed of make nile. - Needed to make vitamin D - Part of the myelin which coats the nerve cells.

Which fatty acids are essential?

- Omega-3 - Omega-6

Explain the functions of lipids in your body?

- Part of the cell membrane. - Insulates the body. - Source of energy. - Protects the body organs. - Provides essential fatty acids. - Essential for digestion, absorption and transport of fat soluble vitamins A,D,E,K and phytochemicals.

Identify a saturated, monounsaturated or polyunsaturated fatty acids.

- Saturated Fatty Acids: Ground beef & Eggs. - Monounsaturated Fatty Acid: Olives & Avocados. - Polyunsaturated Fatty Acid: Nuts & Vegetable Oil.

What are other characteristics of the fatty acids: Saturated, monounsaturated and polyunsaturated?

- Saturated fatty acid: Animal products (meat poultry, seafood (low), eggs, dairy products, lard, butter) and coconut, palm and other tropical oils. - Monounsaturated fatty acid: May have neutral or slightly beneficial health benefits. Found in canola oil, olives, olive oil, most nuts & avocado. - Polyunsaturated fatty acid: There ate 2 essential fatty acids in this group. They are essential because the body can't synthesize PUFA's with the double bond in the n-3 or n-6 position.

What are the structural differences between saturated, monounsaturated and polyunsaturated fatty acids?

- Saturated fatty acid: Contain no carbon double bonds. - Monounsaturated Fatty acid: Contain one carbon double bonds. - Polyunsaturated fatty acid: Contain more than one carbon double bonds.

What is EPA, DHA & arachidonic acid?

-Eicosapentaenoic acid (EPA): A 20 carbon omega 3 polyunsaturated fatty acid found in fish that can be synthesized from a-linolenic acid but may be essential in humans under some conditions. -Docosahexaenoic acid (DHA): A 22 carbon omega 3 polyunsaturated fatty acids found in dish that mat be needed in the diet of newborns. It can be synthesized from a-linolenic. - Arachidonic acid: a 20 carbon omega 6 polyunsaturated fatty acid that can be synthesized from linolenic.

Be familiar with the sequence of events during digestion and absorption of lipids.

1. A small amount of lipid digestion occurs in the stomach due to lipase's produced in the mouth and stomach. 2. The liver produces bile, which is stored in the gallbladder and released into the small intestine to aid in digestion and absorption of fat. 3. The pancreas produces the enzyme pancreatic lipase which is released into the small intestine to break down triglycerides into monoglycerides, fatty acids and glycerol. 4. In the small intestine, the products of fat digestion and bile form micelles, which move close enough to the microvilli to allow lipids to diffuse into the mucosal cells. 5. Inside the mucosal cells, fatty acids and monoglycerides are reassembled into triglycerides and incorporated into lipid transport particles which enter the lymph. 6.Since fat absorption in the small intestine is efficient, very little fat is normally lost in the feces.

Identify oils/foods that are high in monounsaturated fat

Canola Oil, Hazelnuts & Avocado.

Where do LDL's carry cholesterol?

Carries cholesterol in the blood to the tissue.

Identity foods that are high in saturated fat

Coconut, Butter & Sausage.

Identify oils/foods that are high in polyunsaturated fat

Coffee, Vegetable Oil & Mayonnaise.

What foods have trans fats?

Cookies, crackers, cakes & french fries.

What is the framingham study?

Created the concept of risk factors and prevention of cardiovascular disease.

Which foods contain cholesterol?

Egg yolks, beef liver & salmon.

What is the function of triglycerides?

Essential for digestion, absorption and transport of fat soluble vitamins A,D,E,K.

What molecules make up a lipid?

Fat, waxes and sterols.

What are dietary sources of omega 3 fatty acids (alpha linolenic acid)?

Flaxseed oil, salmon, soybean & sardines.

How does saturated fats and trans fats in the diet effect cholesterol levels?

Foods with saturated fats and trans fats increase cholesterol in the blood and raise CVD risk.

What dietary factors lead to heart disease?

High blood pressure, high cholesterol, overweight & smoking.

What is the function of bile salts?

Is to solubilize ingested fat and fat-soluble vitamins, facilitating their digestion and absorption.

What happens to the endothelium with the progression of atherosclerosis?

It is damaged by cholesterol, high blood pressure, obesity, smoking, diabetes and lack of exercise.

What is a normal blood triglyceride level?

Less than 150 mg/dl

Which lipids are needed in the diet and why are they important?

Lipids are a collective word for the fats and oils in our bodies. They serve several functions in our body. These include storing high-dense energy for cells, serving as a protective layer for our bodily organs and acting as a vehicle for transportation of certain nutrients.

Are lipids soluble/insoluble in water or fat.

Lipids are insoluble in water/fat

What are health benefits of omega 3's?

Lowers blood pressure, helps depression, asthma, ADHD & alzheimer's disease.

Which lipids contain double bonds?

Monounsaturated & Polyunsaturated fats.

Where does most fat digestion take place?

Most fat digestion takes place in the small intestine.

Which oils are healthy?

Olive Oil

What are trans fatty acids?

Partially hydrogenated vegetable oil, commercially baked goods (cookies, crackers, cakes) fried foods (such as doughnuts and french fries) shortening and margarine.

What are eicosanoids?

Regulatory molecules that came be synthesized from omega-3 and omega-6 fatty acids.

Where do HDL's carry cholesterol ?

Removes cholesterol from the tissues and carries it back to the liver for elimination.

Which lipids contain single bonds?

Saturated fats

Different types of lipids

Saturated, Monounsaturated & Polyunsaturated.

What are dietary sources of omega 6 fatty acids (linolenic acid)?

Sunflower oil, soybean oil, sesame seeds & walnuts.

Does the american diet have the correct ratio of omega 3's to omega 6's?

The US diet contain a higher ratio of omega 6 to omega 3 fatty acids than is optimal to health. Increasing consumption of foods that are rich in omega 3 fatty acids increase the proportion of omega-3 eicosanoids. This reduces the risk of heart disease by decreasing inflammation, lowering blood pressure and reducing blood clotting.

What causes Atherosclerosis?

The buildup of fat, cholesterol and other substances that are together called plaque.

Is cholesterol essential or is it synthesized in the body?

The cholesterol your body needs can be synthesized in your body.

What are the health implication of eicosanoids from EPA vs. arachidonic acid on inflammation, blood clotting and blood pressure?

The effect of an eicosanoid on these functions depends on the fatty acid from which it was made. When the omega-6 fatty acid arachidonic acid is starting material, the eicosanoid synthesized increase blood clotting; when the omega-3 fatty acid EPA is the starting material, the eicosanoid made decrease blood clotting. Increasing consumption of foods that are rich in omega-3 eicosanoids. This reduces the risk of heart disease by decreasing inflammation, lowering blood pressure and reducing blood clotting.

What are triglycerides?

The major type of lipid in food and the body, consisting of three fatty acids attached to a glycerol molecule.

How does the ratio of omega-3 and omega-6 fatty acids in the diet impact the production of eicosanoids?

The ratio of dietary omega-6 to omega-3 fatty acids affects the balance of the omega-6 and omega-3 fatty acids in the body and therefore, the balance of the omega-6 and omega-3 eicosanoids are produced.

Give the function of phospholipids in the body.

They are an important component of cell membranes. It is also used to synthesize the neurotransmitter acetycholine, which activates muscles and plays an important role in memory.

How do fat replacers work?

They reduce the amount of fat in food, and they usually reduce the calorie content of the food.

What is adipose tissue?

Tissue found under the skin and around body organs that is composed of fat-storing cells.

Which lipid group is most abundant in our bodies?

Triglycerides

How are triglycerides transported in the blood?

Triglycerides are carried by chylomicrons and are either used for energy or stores in adipose tissue.

How are triglycerides used in the body?

When you eat, your body converts any calories it doesn't need to use right away into triglycerides. The triglycerides are stored in your fat cells. Later, hormones release triglycerides for energy between meals.