Nutrition

Nutrients: The Biochemical units of

nutrition Body requires fuel to provide Body requires fuel to provide

energy for cellular metabolism and energy for cellular metabolism and repair, organ function, growth & repair, organ function, growth & body movementbody movement

Food is the fuel that keeps the Food is the fuel that keeps the machine that is our body runningmachine that is our body running

Energy requirements based on:

Basal metabolic rate (BMR)-Energy Basal metabolic rate (BMR)-Energy needed to maintain life sustaining needed to maintain life sustaining ( Breathing, circulation, temperature, ( Breathing, circulation, temperature, heart rate)heart rate)

Resting Energy Expenditure (REE)-Resting Energy Expenditure (REE)-measurement that accounts for BMR measurement that accounts for BMR plus energy needed to digest food & plus energy needed to digest food & perform mild activity. Accounts for 60-perform mild activity. Accounts for 60-70% of our daily needs70% of our daily needs

Nutrients

Elements necessary for body Elements necessary for body processes & functionprocesses & function

6 Categories6 Categories Carbohydrates, Proteins, Fats, Carbohydrates, Proteins, Fats,

Water, Vitamins, MineralsWater, Vitamins, Minerals

Carbohydrates

Main source of energy (55-60% of Main source of energy (55-60% of calories in diet)calories in diet)

Each gram = 4 kcalEach gram = 4 kcal Composed of carbon, hydrogen & oxygenComposed of carbon, hydrogen & oxygen Main source of fuel (glucose) for brain, Main source of fuel (glucose) for brain,

skeletal muscle during exercise, RBC skeletal muscle during exercise, RBC &WBC production, cell function of renal &WBC production, cell function of renal medullamedulla

Obtained from plant foods, except for Obtained from plant foods, except for lactose (milk, sugarlactose (milk, sugar))

Simple Carbohydrates

Classified according to saccharidesClassified according to saccharides Monosaccharide- glucose(dextrose), Monosaccharide- glucose(dextrose),

fructose, galactose (building blocks of fructose, galactose (building blocks of all other CHO)all other CHO)

Glucose- blood sugar (normal fasting Glucose- blood sugar (normal fasting BS=70-100 mg/ml)BS=70-100 mg/ml)

Disaccharide- sucrose, lactose, Disaccharide- sucrose, lactose, maltose,maltose,

Sugar alcohols-sugar replacersSugar alcohols-sugar replacers Artificial sweetnersArtificial sweetners

Complex Carbohydrates

Polysaccharides are complex Polysaccharides are complex carbohydrates carbohydrates

Starches, glycogen, & fiber are Starches, glycogen, & fiber are polysaccharidespolysaccharides

Starches are the major source of CHO in Starches are the major source of CHO in diet (grains, cereals, breads, pasta, diet (grains, cereals, breads, pasta, starchy vegetables & legumes)starchy vegetables & legumes)

Glycogen- animal starch (found in liver & Glycogen- animal starch (found in liver & muscle tissue, provides immediate fuel muscle tissue, provides immediate fuel for muscle action for muscle action

Dietary Fiber

Plant foods that cannot be broken Plant foods that cannot be broken down by body to digestdown by body to digest

Fiber eliminated by intestinal wasteFiber eliminated by intestinal waste Adds volume, no fuel or energyAdds volume, no fuel or energy Fiber in diet helps promote regularity Fiber in diet helps promote regularity

of bowel movements, helps in of bowel movements, helps in regulating blood sugar, reducing regulating blood sugar, reducing cholesterol, may promote weight cholesterol, may promote weight loss, reduce risk of colon cancer & loss, reduce risk of colon cancer & diverticular diseasediverticular disease

Functions of CHO

Provide fuel (CHO primary source)Provide fuel (CHO primary source) Spare body protein (body can convert Spare body protein (body can convert

protein to glucose; body will break protein to glucose; body will break down internal protein stores before down internal protein stores before fat stores in absence of CHO)fat stores in absence of CHO)

Helps prevent ketosis (partially Helps prevent ketosis (partially broken down fats accumulate in blood broken down fats accumulate in blood as ketones)as ketones)

Enhance learning & memory Enhance learning & memory (Glucose)(Glucose)

Proteins

Provide a source of energyProvide a source of energy 4 kcal per gram4 kcal per gram Essential for synthesis of body tissue Essential for synthesis of body tissue

in growth, maintenance & repairin growth, maintenance & repair Collagen, hormones, enzymes, Collagen, hormones, enzymes,

immune cells, DNA, RNA are immune cells, DNA, RNA are composed of proteincomposed of protein

Blood clotting, fluid regulation, & Blood clotting, fluid regulation, & acid-base balance require proteinacid-base balance require protein

Protein Composed of carbon, hydrogen, Composed of carbon, hydrogen,

oxygen,& nitrogenoxygen,& nitrogen There are essential and There are essential and

nonessential amino acidsnonessential amino acids Complete and incomplete proteinsComplete and incomplete proteins Essential amino acids: isoleucine, Essential amino acids: isoleucine,

leucine, lysine, threonine, leucine, lysine, threonine, tryptophan, methionine, histidine, tryptophan, methionine, histidine, valine, phenylalaninevaline, phenylalanine

Protein

Albumin & Insulin are simple Albumin & Insulin are simple proteinsproteins

Lipoprotein is a complex protein Lipoprotein is a complex protein (Lipid & protein)(Lipid & protein)

Complete & Incomplete proteinsComplete & Incomplete proteins

Protein

Nitrogen balance- intake & output of Nitrogen balance- intake & output of nitrogen equalnitrogen equal

When intake of nitrogen exceeds When intake of nitrogen exceeds output, body is in a positive nitrogen output, body is in a positive nitrogen balance (growth, pregnancy, balance (growth, pregnancy, maintenance of lean muscle mass & maintenance of lean muscle mass & vital organs, wound healingvital organs, wound healing

The extra nitrogen is used for The extra nitrogen is used for building, repairing, & replacement of building, repairing, & replacement of tissuestissues

Protein

Negative Nitrogen balance- Body Negative Nitrogen balance- Body loses nitrogen faster than it gains itloses nitrogen faster than it gains it

Infection, Sepsis, Fever, starvation, Infection, Sepsis, Fever, starvation, head injury, trauma, burnshead injury, trauma, burns

Increased nitrogen loss is the result Increased nitrogen loss is the result of body tissue destruction or loss of of body tissue destruction or loss of nitrogen containing body fluidsnitrogen containing body fluids

How protein functions in the body

Provision of structureProvision of structure Growth & maintenance of tissueGrowth & maintenance of tissue Regulation of body processes Regulation of body processes

(hormones, enzymes, (hormones, enzymes, nucleoproteins)nucleoproteins)

Development of immunityDevelopment of immunity Circulation of blood and nutrientsCirculation of blood and nutrients Backup source of energyBackup source of energy

Fats

Fats(lipids) are the most calorically Fats(lipids) are the most calorically densedense

Composed of carbon, hydrogen, & Composed of carbon, hydrogen, & oxygen (basic structural oxygen (basic structural unit=glycerol)unit=glycerol)

9 kcal per gram9 kcal per gram Composed of monoglycerides, Composed of monoglycerides,

diglycerides, & triglyceridesdiglycerides, & triglycerides Lipogenesis- Synthesis of fatty acidsLipogenesis- Synthesis of fatty acids

Fats

Fatty acids can be Saturated or Fatty acids can be Saturated or Unsaturated, Monounsaturated, or Unsaturated, Monounsaturated, or polyunsaturated & Trans-fatty polyunsaturated & Trans-fatty acidsacids

Essential Fatty Acids (Linoleic, Essential Fatty Acids (Linoleic, Linolenic) must be supplied by dietLinolenic) must be supplied by diet

Nonessential fatty acidsNonessential fatty acids Necessary for metabolic processesNecessary for metabolic processes HDL vs LDLHDL vs LDL

Fats

Animal fats are high in saturated Animal fats are high in saturated fatty acidsfatty acids

Vegetable fats are high in Vegetable fats are high in unsaturated and polyunsaturated unsaturated and polyunsaturated fatty acidsfatty acids

Functions of Fats

Fuel sourceFuel source Vehicle for fat soluble vitaminsVehicle for fat soluble vitamins Satiety valueSatiety value Sources of essential fatty acidsSources of essential fatty acids Organ protectionOrgan protection LubricationLubrication InsulationInsulation Cell membrane structureCell membrane structure

Cholesterol

Not a true fat, classified as a sterolNot a true fat, classified as a sterol Body manufactures 1000 mg dayBody manufactures 1000 mg day Component of bile salts, essential Component of bile salts, essential

component of cell membrane, component of cell membrane, necessary for production of several necessary for production of several hormones (cortisone, estrogen hormones (cortisone, estrogen adrenaline, testosterone)adrenaline, testosterone)

Elevated blood levels is a major risk Elevated blood levels is a major risk factor for CAD ( < 200 mg/dL optimal)factor for CAD ( < 200 mg/dL optimal)

Water

Critical component of bodyCritical component of body Cell function depends on a fluid Cell function depends on a fluid

environmentenvironment 60-70% of body weight60-70% of body weight Muscle contains more water than fatMuscle contains more water than fat Infants have higher total body waterInfants have higher total body water Fluid needs met by ingesting fluids & Fluid needs met by ingesting fluids &

solid food high in water content solid food high in water content (fruits & veggies)(fruits & veggies)

Vitamins

Organic substances present in Organic substances present in small amounts in foodsmall amounts in food

Essential for normal metabolismEssential for normal metabolism Body depends on dietary intakeBody depends on dietary intake Vitamin content higher in fresh Vitamin content higher in fresh

foodsfoods Classification by solubility: water Classification by solubility: water

or fator fat

Vitamins

Fat Soluble- Vitamins A, D, E, KFat Soluble- Vitamins A, D, E, K Can be stored in bodyCan be stored in body Provided through dietary intake except for Provided through dietary intake except for

Vitamin DVitamin D Antioxidant role of vitaminsAntioxidant role of vitamins Water Soluble-Vitamin C, B Complex (8 Water Soluble-Vitamin C, B Complex (8

vitamins)vitamins) Cannot be stored in body, provided by Cannot be stored in body, provided by

dietary intakedietary intake Vitamins are catalysts in biochemical Vitamins are catalysts in biochemical

reactionsreactions

Functions of Fat-Soluble Vitamins

Vitamin A: vision, healthy epithelial Vitamin A: vision, healthy epithelial tissue, proper bone growth, energy tissue, proper bone growth, energy regulationregulation

Vitamin D: promotes normal bone Vitamin D: promotes normal bone mineralization, plays a role in calcium mineralization, plays a role in calcium and phosphorus absorptionand phosphorus absorption

Vitamin E: antioxidant role (protects Vitamin E: antioxidant role (protects Vitamin A & unsaturated fatty acids from Vitamin A & unsaturated fatty acids from oxidationoxidation

Vitamin K: blood clotting, bone Vitamin K: blood clotting, bone metabolismmetabolism

Functions of Water-Soluble Vitamins

Vitamin C: collagen synthesis, Vitamin C: collagen synthesis, powerful antioxidant, adrenal powerful antioxidant, adrenal gland function, iron absorption, gland function, iron absorption, folic acid conversionfolic acid conversion

B-Complex: co-enzyme in B-Complex: co-enzyme in numerous metabolism numerous metabolism mechanismsmechanisms

Minerals

Inorganic elements essential to Inorganic elements essential to the body as catalysts in the body as catalysts in biochemical reactionsbiochemical reactions

Macrominerals-Body requires Macrominerals-Body requires 100mg or more100mg or more

Trace elements-Body needs less Trace elements-Body needs less than 100 mgthan 100 mg

Minerals

Macrominerals- Calcium, Sodium, Macrominerals- Calcium, Sodium, Potassium, Phosphorus, Potassium, Phosphorus, Magnesium, Sulfur, and ChlorideMagnesium, Sulfur, and Chloride

Trace Elements- Iodine, Fluoride, Trace Elements- Iodine, Fluoride, Iron, Selenium, Zinc, Copper, Iron, Selenium, Zinc, Copper, Selenium, Manganese, ChromiumSelenium, Manganese, Chromium

Metabolism

Catabolism- Breakdown of Catabolism- Breakdown of biochemical substances into biochemical substances into simpler substances (starvation)simpler substances (starvation)

All body cells except RBC & All body cells except RBC & neurons can oxidize fatty acids neurons can oxidize fatty acids into ketones for energy in the into ketones for energy in the absence of dietary CHOabsence of dietary CHO

Metabolism

Biochemical reaction with cellsBiochemical reaction with cells Anabolic or CatabolicAnabolic or Catabolic Anabolism- Building of more Anabolism- Building of more

complex substances, occurs when complex substances, occurs when lean muscle is added through diet lean muscle is added through diet & exercise& exercise

Amino acids are anabolized into Amino acids are anabolized into tissue, hormones, & enzymestissue, hormones, & enzymes

Dietary Guidelines

Recommended dietary allowancesRecommended dietary allowances Food Guidelines-Food PyramidFood Guidelines-Food Pyramid Daily values on food labels (based Daily values on food labels (based

on 2000 kcal/day)on 2000 kcal/day)

Conditions affecting Digestion

CVACVA GERDGERD Hiatal HerniaHiatal Hernia Gastric BypassGastric Bypass H-PyloriH-Pylori UlcersUlcers ObstructionObstruction GallbladderGallbladder

Malabsorption Malabsorption syndromessyndromes

Lactose IntoleranceLactose Intolerance Celiac diseaseCeliac disease IBSIBS IBD (colitis, Crohns)IBD (colitis, Crohns) DiverticulosisDiverticulosis Diarrhea/Diarrhea/

ConstipationConstipation HemorrhoidsHemorrhoids