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Fats. Also known as lipids Concentrated source of energy Fat serves to Provide a source of energy Insulate the body Cushion organs Aids the absorption of fat-soluble vitamins (vitamins A, D, E, K) Add flavour and texture to foods. Fats. Fats in food are mostly triglycerides
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Fats • Also known as lipids • Concentrated source of energy Fat serves to • Provide a source of energy • Insulate the body • Cushion organs • Aids the absorption of fat-soluble vitamins (vitamins A, D, E, K) • Add flavour and texture to foods Sport Books Publisher
Fats Fats in food are mostly triglycerides Triglycerides = 1 glycerol + 3 fatty acids • The storage form of fat Sport Books Publisher
Fats Fats can be classified as: • Saturated • Monounsaturated • Polyunsaturated These classifications are based on the degree of saturation or number of double bonds that exist between carbon atoms Saturated = No double bonds (H on all C’s) • Hardest Monounsaturated = One double bond (2 C’s without H’s) • Softer Polyunsaturated = Two or more double bonds (2 or more C’s without H’s) • Softest Sport Books Publisher
Saturated Fat Every available Carbon holds a Hydrogen Monounsaturated Fat One place where Hydrogen's are missing Polyunsaturated Fat Two or more places where Hydrogen’s are missing Sport Books Publisher
Saturated Fats • Food usually contains more than one type of fat • The dominant fat determines the characteristics of the fat • Saturated fats are solid at room temperature • Saturated fat is found predominantly in animal products • Saturated fat has also been linked to cardiovascular disease Sport Books Publisher
Unsaturated Fats • Monounsaturated and polyunsaturated fats usually come from plant sources • Unsaturated fat is liquid at room temperature (oil) • More desirable, not linked to cardiovascular disease • Unsaturated fats appear to lower blood cholesterol • Also shown to reduce the risk of heart disease Sport Books Publisher
Oils – Saturated or Unsaturated Sport Books Publisher
Hydrogenation The process where H is added to an unsaturated fat, turning it into a saturated fat. • Hydrogenated fats and oils are created from unsaturated fats and are used to prevent spoiling and to add texture. • If an oil is processed, chances are it underwent hydrogenation, turning it into a saturated fat. Sport Books Publisher
Cholesterol A type of lipid produced by the liver and ingested through animal products. Functions: • Aids in the production of hormones • Aids in production of bile • Converts sunshine to Vitamin D • Insulation of nerve fibres • Aids in cell membrane permeability
Cholesterol • Elevated intake of saturated fats may increase blood cholesterol levels • Hydrogenation produces trans fatty acids that may increase blood cholesterol • These processed oils are hydrogenated to increase their shelf life and reduce the chance of spoilage • Increased blood cholesterol and triglyceride levels have been implicated with the development of heart disease Sport Books Publisher
Lipoproteins - Chylomicrons When triglycerides are broken down in the SI, glycerol, short chain fatty acids, long chain fatty acids and monoglycerides are formed. • Glycerol & short chain fatty acids are able to freely pass through the GI tract lining and into the blood stream • Monoglycerides and long chain fatty acids are too big for absorption so they reform into triglycerides which combine with protein to form the lipoprotein Chylomicron Transports food fats through the water body fluid to the liver and other tissues
Lipoproteins – VLDL, LDL & HDL Very Low Density Lipoproteins (VLDL) • Formed in the liver • Transport triglycerides and other lipids from the liver to body cells for use Low Density Lipoproteins (LDL) • Made from VLDL, in the liver, once they have donated their fat to the body and picked up cholesterol • Transport lipids from the liver to other tissues, such as muscle and fat High Density Lipoproteins (HDL) • Made in the liver • Carry cholesterol from the body cells to the liver for disposal
Carbohydrates Primary source of energy • 60% of daily Calories There are three groups based on the number of saccharides: 1. Monosaccharides - Sugars 2. Disaccharides - Sugars 3. Polysaccharides – Starch & Fibre Sport Books Publisher
Monosaccharides • Simplest sugar • Include glucose, fructose, galactose • Glucose makes up the blood sugar • the brain & nervous system are fueled by glucose exclusively • Glucose is found in vegetables, fruit & honey • Monosaccharides can be absorbed directly into your blood stream with having to be digested first Fructose - fruits and berries Galactose – found in milk *milk is the only animal dervied food that contains significant amount of carbs.* Sport Books Publisher
Disaccharides • The combination of two monosaccharides • One monosaccharide is always glucose lactose = glucose + galactose maltose = glucose + glucose sucrose = glucose + fructose • Your body must digest disaccharides before they can be absorbed, separating them into monosaccharide's with help from various enzymes Sport Books Publisher
Polysaccharides • Complex carbohydrates composed of chains of many glucose molecules • Found in vegetables, fruit, grains • Plants storage form of glucose • Starches often contain many vitamins, minerals, water & protein • Insoluble substance allowing it to withstand the elements when combined into granules (small grains) Sport Books Publisher
Fibre • Fibres are polysaccharides, whose glucose molecules are held together by bonds that the human digestive enzymes cannot break • Fibre includes plant substances that cannot be digested by the body • Adds bulk to feces to facilitate elimination Sport Books Publisher
Fibre Sources Rich sources of fibre include: • Fruit • Legumes (beans, peas, lentils, etc.) • Oats • Barley Other sources include: • Wheat • Grains (rice, corn, rye) • Vegetables • Whole grain foods (cereal germ, endosperm, bran) Sport Books Publisher
Soluble Fibre Lowers blood cholesterol Slows absorption of glucose Readily dissolves in water May be broken down to absorbable products by bacteria in the digestive tract Insoluble Fibre Facilitates feces elimination Can prevent constipation, lower intestinal tract cancer Soluble vs. Insoluble Fibre Sport Books Publisher
Carbohydrates • Liver and muscles store excess glucose in the form of glycogen • Carbohydrates consumed in excess of storage capacity as glycogen are stored as fat • An important component of the diet for athletes competing in events of both long and short duration activities Sport Books Publisher