Chapter 08 - fat

Hydrophobic

Water fearing – will not dissolve in, or react with, water

Cardiovascular Disease

Conditions involving the narrowing or blockage of blood vessels that can cause a heart attack, chest pain, or stroke.

Lipids

Compounds that are fatty acids or their derivatives.

Fatty acids

Organic compounds with long hydrocarbon chains that are saturated or unsaturated.

Phospholipids

Comprised of two fatty acids, a phosphate group, and a glycerol molecule. The phosphate group head is water soluble and the fatty acid tail is water insoluble. They align themselves to form the cell membrane.

Cholesterol

A lipid-like waxy substance found in all cell membranes, most body tissues, and body fluids – the body needs some cholesterol to make steroid hormones and vitamin D. Some cholesterol is obtained from foods like eggs, cheese, and shellfish. Most cholesterol is produced by the body.

Saturated Fatty Acids

Fatty acids that have the maximum number of hydrogen molecules and contain only single bonds between their carbon atoms. Foods high in saturated fatty acids are usually solid at room temperature (like butter) and are often found in animal fat, palm oil, and coconut oil.

Unsaturated Fatty Acids

Fatty acids that have one or more double bonds between the carbon atoms in the carbon chain. These are typically liquid at room temperature, relatively unstable, and are prone to oxidative damage.

Hydrogenation

The process of forcing hydrogen into vegetable oil to create a semi-solid or solid saturated fat.

Oxidative Damage

The imbalance of free radicals and antioxidants – free radicals are oxygen-containing molecules with an uneven number of electrons, which makes them susceptible to react with other molecules.

Monounsaturated Fatty Acids

Unsaturated fats that have one unsaturated carbon molecule (two hydrogen atoms instead of four) or one double bond.

Polyunsaturated Fatty Acids

Unsaturated fats that have two or more double bonds between carbon molecules.

Mediterranean Diet

Based on the traditional foods that people from Greece and Italy eat, including those foods rich in monounsaturated fats such as olive oil, nuts, and seeds.

Trans Fat

An artificial fatty acid that occurs when hydrogen is added to liquid vegetable oils (unsaturated fat) to make them more solid (saturated fat) and have a more stable shelf life.

Low-Density Lipoproteins

Lipoprotein that carries cholesterol from the liver to the cells, known as bad cholesterol.

Triglycerides

The primary storage and transportable form of fats in the body, composed of three free fatty acids bound to a glycerol backbone.

High-Density Lipoproteins

Lipoprotein that carries excess cholesterol away from the cells to the liver where it is turned into bile or excreted, known as the good cholesterol.

Endothelial Dysfunction

Damage that occurs to the endothelium, the thin layer surrounding blood vessels.

GRAS

An acronym for the Generally Recognized as Safe list of any substance that is intentionally added to food – a food additive that has been recognized as safe by a group of experts.

FDA

The U.S. Food and Drug Administration is responsible for protecting the public health by ensuring the safety, efficacy, and security of human and veterinary drugs, biological products, and medical devices, and by ensuring the safety of our nation’s food supply.

Dietary Fat

The fat and oils found in food that is consumed.

Adipose Tissue

The loose connective tissue composed of fat cells for stored energy.

Phospholipids

Comprised of two fatty acids, a phosphate group, and a glycerol molecule – the phosphate group head is water soluble and the fatty acid tail is water insoluble. They align themselves to form the cell membrane.

Lipoproteins

A combination of fat and protein that transports cholesterol and other lipids to and from various tissues through the blood.

Hydrophilic

Water loving – will dissolve in, and react with, water.

Essential Fatty Acids

Fatty acids that cannot be synthesized, or not in adequate amounts, and, therefore have to be consumed in the diet – they include omega-3 and omega-6 fatty acids.

Fat-Soluble Vitamins

Fat soluble means that a compound or molecule can be dissolved into fat. Fat-soluble vitamins include A, D, E, and K.

Omega-3s (a-Linolenic)

Named based on the position of the first double bond in the carbon chain, Carbon 3, an essential polyunsaturated fatty acid that is found in fish, seafood, flaxseed oil, and walnuts.

Omega-6s (a-Linoleic)

Named based on the position of the first double bond in the carbon chain, Carbon 6, an essential polyunsaturated fatty acid that is found primarily in plant oils such as corn, soybean, and safflower.

EPA 

Abbreviation for eicosapentaenoic acid, essential omega-3 fatty acid found in marine sources including fish and krill, serves as a precursor to various compounds that have anti-inflammatory activities in the body in addition to serving as structural components of the brain and eye tissue. 

DHA

Abbreviation for docosahexaenoic acid, the essential omega-3 fatty acid found in marine sources including fish and krill, highly abundant in the human brain, eyes, and sperm cells.

Dietary Reference Intakes (DRIs)

The recommended intake of various nutrients as determined by the Food and Nutrition Board of the Institute of Medicine - the DRIs include recommendations like the Recommended Dietary Allowance (RDA) and Acceptable Macronutrient Distribution Range (AMDR).

Adequate Intake (AI)

The recommended average daily intake level based on observed or experimentally determined estimates of nutrient intake by groups of apparently healthy people that are assumed to be adequate - the AI is used when an RDA cannot be determined.

Membrane

A thin, soft, pliable layer that acts as a boundary, lining, or partition around an organism or cell.

Selective Permeability

Monitors what materials enter and exit a cell.

Adipocytes

Cells specialized in the storage of fat that makes up adipose tissue.

Emulsifier 

A substance used to bind a hydrophobic and hydrophilic compound.

Enzymes

A protein molecule that acts as a catalyst to bring about a biochemical reaction, thus speeding up the process.

Bile

An alkaline fluid that aids in digestion – it is secreted by the liver and stored in the gall bladder.

Micelle

A compound comprised of bile salts (water-loving) surrounding monoglycerides, free fatty acids, and fat-soluble vitamins (water phobic) in order for absorption to occur.

Lymphatic System

An extensive network of vessels passing through almost all bodily tissues that produce and transport lymph (colorless fluid of white blood cells).

Lipoprotein Lipase

An enzyme found in the endothelium of the cells that breaks down triglycerides into fatty acids and a glycerol for the cell to use.

Endothelium

Cells that line the inner surface of blood vessels and other lymphatic tissue.

Low-Density Lipoprotein

Lipoprotein that carries cholesterol from the liver to the cells, known as bad cholesterol.

High-Density Lipoprotein

Lipoprotein that carries excess cholesterol away from the cells to the liver where it is turned into bile or excreted, known as the good cholesterol.

Beta-Oxidation

The process that occurs within the cell’s mitochondria to produce glycerol and fatty acids.

Acetyl-CoA

A molecule that participates in biochemical reactions in protein, carbohydrate, and lipid metabolism, producing energy.

Ketone Bodies

A group of incompletely metabolized fat fragments that are normally produced during fat metabolism in the absence of adequate carbohydrates.

Adequate Intake (AI)

The recommended average daily intake level based on observed or experimentally determined estimates of nutrient intake by groups of apparently healthy people that are assumed to be adequate. The AI is used when an RDA cannot be determined.