o o o o o o o o o Chapter 1 Macronutrients CHO Lipids Proteins Nutrients Macronutrients CHO Protein Fat Micronutrients Vitamins water and fat soluble Must be obtained from the diet 13 vitamins o Minerals Macrominerals major minerals 100 mg or more day intake Calcium magnesium potassium etc Microminerals trace elements less than 100 mg day Dietary mineral that is needed in minute quantities for proper growth development and physiology of organism Iron zinc selenium etc Functions of Nutrients Promotion of growth and development Anabolic building environment is desirable for optimum growth Provision of energy Energy is from the MACRONUTRIENTS not b vitamins or caffeine as most energy drinks claim Regulates metabolism Maintains structure and integrity This includes cell walls for example Carbohydrates Composed of Carbon Oxygen and Hydrogen CH2O n Can also be expressed as a ratio of 1 2 1 C6H12O6 CHO is an important fuel during exercise CHO rich foods include o o Grains Pasta o Potatoes Rice Beans Sugar or sucrose o o o Different Carbohydrate Categories o Monosaccharides ONE sugar molecule Includes Glucose Fructose o o Galactose Also called dextrose or blood sugar Also called levulose or fruit sugar Disaccharides TWO monosaccharides linked Sucrose glucose fructose Provides 20 25 of daily energy intake in Western diet Examples are beet and cane sugar brown sugar table sugar maple syrup and honey Lactose glucose galactose Examples are milk sugar Maltose glucose glucose Examples are beer cereals germinating seeds only small amounts in our diet o Oligosaccharides THREE to NINE monosaccharides linked Includes Seed legumes peas beans and lentils Not digested well but metabolized by bacteria located in the lower intestine Polysaccharides TEN or MORE monosaccharides linked o 10 to 20 monosaccharides maltodextrin Up to thousands of monosaccharides Includes Pasta Potato etc Starch complex carbohydrate 50 of our total daily CHO intake storage form of CHO in plants Contains two components amylose and amylopectin Amlyose and amylopectin are broken down and digested at different rates o Amylopectin can be digested FASTER because it has multiple branches Has increased surface area allowing it to be more exposed to digestive enzymes Amylose is digested SLOWER because it is a long chain 200 4000 twisted in helical coil Fiber nonstarch structural polysaccharide Exists EXCLUSIVELY in PLANTS Gives bulk binds chemicals and fats and shortens transit time for food Includes Insoluble Cellulose Hemicellulose o Lignin Soluble Pectin Gums Recommended intake o Men 38 g day o Women 25 g day Glycogen Storage polysaccharide found in mammalian muscle 300 900 g and liver 80 100 g Upper limit 15 g kg of bw Consists of irregularly shaped branched polysaccharide polymer Structure is SIMILAR to amylopectin in plant MAJOR source of CHO energy for active muscle during exercise o o o o o o o o o o o o Liver glycogenolysis break down of glycogen extramuscular glucose Functions of Carbohydrates o Energy source o Muscle glycogen and blood glucose can provide 32 kcal minute during very high intensity exercise 1500 2000 kcal 375 500g of TOTAL storage o Exceeding the cells capacity to store glycogen triggers conversion and storage of excess dietary CHO calories as FAT o Affects of Metabolic Mixtures and Spares Protein o Glycogen stores rapidly deplete during these three conditions Starvation Reduced energy intake and low CHO diets Prolonged strenuous exercise o These conditions will trigger an increase need for glucose synthesis or gluconeogenesis from both PROTEIN and the GLYCEROL portion of the fat In extreme cases gluconeogenesis may reduce lean tissue mass o o Metabolic Primer Prevents Ketosis o When glycogen stores are depleted like the scenarios stated above can cause more FAT MOBILIZATION than oxidation o Can cause incomplete fat breakdown which then causes an accumulation of acetone like by products called KETONE BODIES As a result acidosis or ketosis can occur o Fuel for CNS o CNS requires CHO to function properly o Brain uses blood glucose as its fuel Glycemic Load o Glycemic index provides a measure of how quickly blood sugar levels rise after eating a particular type of food o GI ratio of BG response COMPARED to white bread o Therefore white bread 100 100 on the glycemic index o When blood glucose spikes there is a hormone response to foods o Hyperinsulinemia o Stimulation of fat synthesis o Increased oxidative damage and inflammation o Rebound hypoglycemia can lead to over eating Glycemic Index vs Glycemic Load o Glycemic index the food item and 50 g of pure glucose o Glycemic load o GI g of CHO serving 100 High 20 Medium 11 19 Low 10 Fats SECOND major macronutrient They dissolve poorly in water o Categories Simple Neutral fats consists primarily of triglycerides o Comparison of blood sugar response increase between consuming 50 g of CHO from Triacylglycerols major storage form in fat in adipose cells 98 of dietary lipids o o Contains a glycerol 3 carbon OH molecule o Three fatty acids attach to glycerol molecule to form TG Triglycerides combined with other chemicals phospholipids lipoproteins Make up cell integrity and cell surface Compound Derived Formed from simple and compound lipids Contain hydrocarbon rings i e cholesterol Types of Fatty Acids Saturated fatty acids SFA Unsaturated fatty acids UFA o No double bonds and carbons are completely saturated with hydrogens o Contains a number of double bonds along the carbon chain Monounsaturated fatty acids MUFA Contains only one double bond Includes canola oil olive oil safflower and sunflower oil Liquid at ROOM temperature Polyunsaturated fatty acids PUFA These are you essential fatty acids like omega 6 and omega 3 Can either promote inflammation or inhibit inflammation o Alpha linolenic omega 3 Omega 3 Alpha linolenic acid DHA docosahexanoic acid or EPA eicosapentaenoic acid o Linoleic omega 6 Note Triglyceride synthesis occurs by esterification condensation or dehydration synthesis Omega 6 Linoleic acid Arachidonic acid Health related Effects Archidonic acid Omega 6 o o Increases blood clotting Increases inflammatory responses EPA DHA Omega 3 o Decreases blood clotting o Reduces heart attack o Decreases inflammation o Excess may cause hemorrhagic stroke o Other possible uses Lowers triglyceride levels Rheumatoid arthritis Behavioral disorders o In humans though it is 14 carbons to 24 carbons Length of Fatty Acid Chains Can vary in length Short chain fatty acids