Chapter 5: Lipids

Omega 6 Fatty Acid

An unsaturated fatty acid with the first double bond on the sixth carbon from the methyl end

Omega-3 Fatty Acid

An unsaturated fatty acid with the first double bond on the third carbon from the methyl end

Phospholipids

Any of a class of fat-related substances that contain phosphorus, fatty acids, and a nitrogen-containing base. The phospholipids are an essential part of every cell.

Monoglyceride

A breakdown product of a triglyceride consisting of one fatty acid attached to a glycerol backbone.

Diglyceride

A breakdown product of a triglyceride consisting of two fatty acids bonded to a glycerol backbone

Sterol

A compound containing a multi-ring (steroid) structure and a hydroxyl group (-OH). Cholesterol is a typical example.

Lipoproteins

A compound found in the bloodstream containing a core of lipids with a shell composed of proteins, phospholipids, and cholesterol.

Emulsifier

A compound that can suspend fat in water by isolating individual fat droplets, using a shell of water molecules or other substances to prevent the fat from coalescing

Saturated Fatty Acid

A fatty acid containing no carbon-carbon double bonds. 4 bonds each: 2 with carbon and 2 with hydrogen. Straight and Linear. Animal fats are high in saturated fat

Monounsaturated Fatty Acid

A fatty acid containing one carbon-carbon double bond. -Canola and Olive Oils

Polyunsaturated Fatty Acid

A fatty acid containing two or more carbon-carbon double bonds. -Corn, soybean, sunflower, and safflower oils

Long-chain Fatty Acid

A fatty acid that contains 12 or more carbons

Cis Fatty Acid

A form of an unsaturated fatty acid that has the hydrogens lying on the same side of the carbon-carbon double bond. -polyunsaturated fats are often in the cis form.

Trans Fatty Acid

A form of an unsaturated fatty acid, usually a monounsaturated one when found in food, in which the hydrogens on both carbons forming the double bond lie on opposite sides of that bond. -allows backbone to be straighter

Lecithin

A group of compounds that are major components of cell membranes. A phospholipid

Glycerol

A three-carbon alcohol used to form triglycerides

Cholesterol

A waxy lipid found in all body cells. It has a structure containing multiple chemical rings that is found only in foods that contain animal products.

Acid Group

Alpha end of a fatty acid

Lipoprotein Lipase

An enzyme attached to the cells that form the inner lining of blood vessels; it breaks down triglycerides into free fatty acids and glycerol.

Alpha-Linolenic Acid

An essential omega 3 fatty acid with 18 carbons and three double bonds

Linoleic Acid

An essential omega 6 fatty acid with 18 carbons and two double bonds

DHA

An omega 3 fatty acid with 22 carbons and six carbon-carbon double bonds. It is present in large amounts of fatty fish and is slowly synthesized in the body from alpha-linolenic acid. DHA is especially present in the retina and brain

Arachidonic Acid

An omega 6 fatty acid made from linoleum acid with 20 carbon atoms and four carbon-carbon double bonds

Oleic Acid

An omega 9 fatty acid with 18 carbons and one double bond

Rancid

Containing products of decomposed fatty acids that have an unpleasant flavor and odor

Lipase

Fat-digesting enzyme produced by the salivary glands, stomach, and pancreas.

Essential Fatty Acids

Fatty acids that must be supplied by the diet to maintain health. Currently, only linoleum acid and alpha-linolenic acid are classified as essential.

Fatty Acid

Found in triglycerides. A long chain of carbons bonded together and flanked by hydrogens.

Fats

Lipids that are solid at Room temp

Chylomicron

Lipoprotein made of dietary fats surrounded by a shell of cholesterol, phospholipids, and protein. Chylomicrons are formed in the absorptive cells of the small intestine after fat absorption and travel through the lymphatic system to the bloodstream

Methyl Group

Omega end of the fatty acid

Recommendations for fat intake

Reduce consumption of saturated fat in population ages 2 years and older to 9.5% of total calorie intake 2010 Dietary Guidelines AMDR 20% to 35% of calories, 44 to 78 grams (based on a 2000 cal diet) AHA recommendations: 20-30% of total kcal from fat, 7-10% can come from saturated/trans fat, 200-300 mg cholesterol/day

True

T/F Lipids do not readily dissolve in water

Hydrogenation

The addition of hydrogen to a carbon-carbon double bond producing a single carbon-carbon bond with two hydrogens attached to each carbon.

Unsaturated Fatty Acid

The carbon chain of a fatty acid contains a double bond, those carbons in the chain have fewer bonds to share with hydrogen. C-C has a double bond instead of 2H --Liquid at room temp

Total Parenteral Nutrition

The intravenous feeding of all necessary nutrients, including the most basic forms of protein, carbohydrates, lipids, vitamins, minerals, and electrolytes.

VLDL

The lipoprotein created in the liver that carries cholesterol and lipids that have been taken up or newly synthesized by the liver

HDL

The lipoprotein in the blood that picks up cholesterol from dying cells and other sources and transfers it to the other lipoproteins in the bloodstream, as well as directly to the liver; low HDL increases risk for heart disease

Triglyceride

The major form of lipid in the body and in food. It is composed of three fatty acids bonded to glycerol, an alcohol. -most common type of lipid found in body and in foods.

Eicosanoids

a class of hormone compounds, including the prostaglandins, derived from polyunsaturated fatty acids such as arachidonic acid and involved in the cellular activity affecting practically all important functions in the body.

EPA

an omega 3 fatty acid with 20 carbons and five carbon-carbon double bonds. It is present in large amounts in fatty fish and is slowly synthesized in the body from alpha-linolenic acid.

Oils

lipids that are liquid at room temp

LDL

the lipoprotein in the blood containing primarily cholesterol; elevated LDL is strongly linked to cardiovascular disease risk