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Unformatted text preview: 8/31/2009 Fat Intake Typical daily intake (< 30% rec) 38% 34% plant 66% animal sources 66% animal sources 15% saturated (<10% rec) General Principles of Nutrition
Chapter 1 Part 2 Cardiovascular Disease Atherosclerosis Plaque builds on artery walls Inflammation Cardiovascular Disease Blood clot increases in size Restricts blood flow Causes Endothelium is damaged Inflammatory responsemacrophages Blood clots form Minerals harden Blood pressure increases Angina Pain or pressure around the heart Heart attack Restricted blood flow to heart Transient ischemic attack or stroke 1 8/31/2009 2 8/31/2009 Cardiovascular Disease Total cholesterol Desirable levels < 200 mg/dl Borderline = 200239 mg/dl High levels = > 240 mg/dl g g/ LDL/HDL ratio Low risk Average risk Moderate risk High risk 3.34.4 4.47.1 7.111.0 >11.0 Lipids Stability Oxygen exposure causes spoilagerancid PUFA's spoil more easily Increase saturation Increase saturation Hydrogenation Prolongs shelf life prevents oxidation Alters texture liquids solids Hydrogenation 3 8/31/2009 Hydrogenation TransFatty Acids Changed from cis to trans configuration and act like saturated fats in the body Partial hydrogenation Partial hydrogenation Higher melting point TransFatty Acids Risk Factors Breast cancer Colon cancer Prostate cancer 4 8/31/2009 Overview of Protein Body is made up of thousands of protein substances More than 30,000 different kinds of protein 3000 studied 3000 studied Overview of Protein Contains carbon, hydrogen, and oxygen And at least one N in structures N is in the form of an amine group (NH2) Unique structure and function Twenty amino acids commonly found in human protein Proteins = 50% of the dry weight of most cells Carboxyl group (COOH) Carboxyl group (COOH) Sulfur, phosphorus, cobalt, iron Amino Acid
NH2 O Overview of Protein Amino Acids Unique side groups Size Shape Electrical charge R C C OH H R group Acid group Nitrogen group 5 8/31/2009 Fig. 6 Protein Organization Polypeptide chain Twists and bends to native conformation Determined by side chains Hydrophilic outer surface Hydrophilic outer surface Hyrophobic folded inside Proteins Order of amino acids Determines shape Proteins Denaturation Uncoiling alters function Heat Stomach acid Stomach acid Irreversible Final shape D Determines function i f i Determines stability 6 8/31/2009 Denaturation of Proteins Denaturation Foods are a means of obtaining amino acids Cooking can make substances available Vitamin biotin (cooked eggs) Denaturation of Proteins Overview of Protein Amino acids20 required by body Essential indispensable Body does not have pathway to synthesize Supplied by diet Supplied by diet Nonessential Can be provided through metabolic pathways Conditionally essential amino acids Heat/acid/alkaline/enzymes Results in alteration of the protein's three dimensional structure Under certain conditions 7 8/31/2009 Dietary Protein Animal proteins Highquality Complete 9 essential amino acids Dietary Protein Allornone principle in protein synthesis If not all of the amino acids are present, protein synthesis does not occur Lowquality q y Incomplete Lacks one or more essential amino acids Limiting amino acids Limiting amino acids Essential amino acid in smallest supply Most plant Cannot meet all amino acid needs Greater variety and amount of plant proteins needed Complementary proteins Mixed diets foods containing different amino acids are combined Limiting Amino Acid
C is the limiting amino acid in this example Complementary Protein
Food 1 Food 2 Combined CCCCC AAAAAAAA CAR CAR CAR RRRRRR CAR CAR R A A A CC CCCC CC CCCC AAAA AA CAR CAR CAR RRR RRR CAR CAR CAR 8 8/31/2009 Vegetarians Protein requirements Variety of plant foods Complementary Grains and legumes Soy protein Soy protein Protein Sedentary 0.81.0 g/kg/d Recreational exercisers 0.81.0 Serious RT, early 1.51.7 Serious RT, established 1.01.2 Serious RT established 1 0 1 2 Serious endurance 1.21.6 Adolescent athlete 1.52.0 Female athletes 15% lower than males Vegans plant sources Lacto vegetarian Milk, milk products Ovolactovegetarian Eggs Role of Proteins Protein content of skeletal muscle 65% total protein of body Structural Proteins Component of tissue structures C ll Cells RNA, DNA Electron carriers NAD, FAD 9 8/31/2009 Structural Proteins Globular Proteins Protein Turnover Replenishment of protein containing structures Amino acid pool Nitrogen Balance Positive nitrogen balance Intake exceeds excretion Synthesis of new tissues Anabolism Tissue building Negative nitrogen balance Negative nitrogen balance Protein used for energy Uses reserves skeletal muscle Catabolism Tissue breakdown 10 8/31/2009 Protein Metabolism Deamination Releases amine group Urea Water
Constitutes 40-70% of the total body mass
Adult body averages 60% Blood about 90% Muscle 65 75% Muscle 6575% Bone 25% Adipose tissue 5% F t fd Fate of deaminated carbon compound i t d b d Make new aa Converted to CHO or fat Catabolized for energy Water Of the total body water 62% exists in the intracellular compartment 38% in the extracellular compartment plasma lymph cerebrospinal fluid and other fluids plasma, lymph, cerebrospinal fluid, and other fluids outside the cell. 11 8/31/2009 Water
Oxygen, waste products Provides protection
Lubrication, cleaning, cushioning Regulates body temperature
Vasodilation of skin vessels Sweat Provides a medium for substances to interact chemically Water Intake
Water intake of an adult
2.0 to 2.8 L/day Water Output Daily water loss occurs from
Urine about 11.5 L Insensible perspiration about 0.500.70 L p p Water vapor in expired air about 0.250.30 L Feces about 0.10 L The average daily water intake comes from Liquid about 1.5 L Liquid 1.5 L Food about 1.0 L Metabolic water about 0.3 L 12 8/31/2009 Dehydration Loss of body water Diarrhea Sweat Vomiting 3% of TBW exercise performance 5% of TBW confusion, disorientation 10% of TBW life threatening 13 ...
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This note was uploaded on 09/20/2009 for the course HEED 3301 taught by Professor Staff during the Spring '08 term at UT Arlington.
- Spring '08