Chapter Five: Carbohydrates
Chapter Five: Carbohydrates HUMNNTR 2310 - 0010
Popular in Fundamentals of Nutrition
Popular in Human Development
verified elite notetaker
This 11 page Class Notes was uploaded by Victoria Gonzalez on Tuesday October 13, 2015. The Class Notes belongs to HUMNNTR 2310 - 0010 at Ohio State University taught by Irene Hatsu in Fall 2015. Since its upload, it has received 12 views. For similar materials see Fundamentals of Nutrition in Human Development at Ohio State University.
Reviews for Chapter Five: Carbohydrates
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/13/15
Chapter 5 Carbohydrates Victoria Gonzalez 1 Carbohydrates contain carbon hydrogen and oxygen a Formula for all carbohydrates CHZOn b Plants are the main source of carbohydrate 2 Simple carbohydrates sugars a Contain either i One sugar unit monosaccharides ii Two sugar units disaccharides b Sources table sugar honey syrups concentrated fruit milk c Monosaccharides hexose sugars because they have 6C CH206 i Glucose basic unit ii Fructose in fruits iii Galactose in milk iv Also two pentose sugars ribose and deoxyribose d Disaccharides 2 monosaccharides linked together by condensation CH2012 i Maltose Glucose Glucose 1 Comes from the breakdown of starch 2 Alpha bond ii Sucrose Glucose Fructose 1 Table sugar 2 Alpha bond iii Lactose Glucose Galactose 1 Milk sugar made by mammals 2 Beta bond cannot be easily broken down by enzymes Gl unease Glucose Ma liaise CH9CIH Gal act ose Glucose Lactose 3 Complex carbohydrates a Oligosaccharides contain 310 sugar units i Ex raf nose and stachyose ii Not digested by human digestive enzymes due to beta bonds iii Bacterial fermentation breaks them down causing gas iv quotBeanoquot contains enzymes to break down oigosaccharides to prevent intestinal gas b Polysaccharides many sugar units i Starch from plants 1 At least 3000 monosaccharides bound together Amylose straight chain polymer Amylopectin highly branched polymer Liked by alpha bonds Used as a thickener and stabilizer in foods because of their structure ii Glycogen stored glucose in animals quotanimal starchquot 1 Many glucose units a Highly branched chain b Alpha bonds 2 23 in muscles for exercise high intensity endurance 3 13 in liver for brain and body U1gtUU Glucose E lqu onse g vuw J Amylase Amaril ciapxtctil n Elycnagern iii Functional ber ber added to foods for health bene ts iv Dietary ber from plants naturally found in food 1 lndigestible plant food 2 Glucose linked with beta bonds 3 Insoluble ber poorly fermented a Cellulose hemicellulose ex wheat bread lignin b Not fermented by the bacteria in the colon c Provides no energy d Advantages i Decreases intestinal transit time ii Decreases constipation iii Lowers risk for diverticular disease iv Lowers risk for colon cancer 4 Soluble ber viscous a Pectin gums some hemicellulose ex oat bran mucilage b Some fermentation by bacteria in the colon c Provides small amount of energy and short chain fatty acids d Advantages i Lowers blood cholesterol levels ii Delays gastric emptying iii Decreases blood glucose levels 4 Sweeteners also carbohydrates a Nutritive sweeteners metabolized to yield energy i Sugars sucrose honey high fructose corn syrup 1 Caloric content 4 kcalsgram 2 No health bene t for one over another a But there is a difference in the long run ii Sugar alcohols sorbitol mannitol xylitol 1 153 kcalgram 2 Absorbed and metabolized slower 3 More than 50 grams must have a warning on label saying excess consumption may have a laxative effectquot b Nonnutritive alternative sweeteners provide no food energy 39 Most are sweeter than sugars Add little or no energy to diet Sugar substitutes Average US intake 24 poundsyearperson Do not promote tooth decay Do not affect blood glucose level Little to no calories Safety is determined by the FDA based on Adequate Daily Intakes ADls I ii iii iv v vi vii viii Saccharin 1 Oldest alternative sweetener 2 Provides trace amounts of kcal 3 3OOX sweeter than sucrose 4 Not heat stable cannot be used to cook a Develops a bitter taste when heated 5 EX Sweet n Low 6 Excessive intake linked to bladder cancer in lab animals 7 No longer listed as potential carcinogen in humans 8 Acceptable daily intake ADI 5mgkg of body weight a Ex 9 packetsday or 3 diet sodas x Aspartame 1 Composed of 2 amino acids phenylalanine and aspartic acid a Those with PKU should avoid aspartame because of its high phenylalanine content 2 Ex NutraSweet and Equal 3 200x sweeter than sucrose 4 4 kcalgram a Same amount of calories as sucrose b But only a trace amount is needed to sweeten c Therefore it does not contribute calories Not heat stable cannot cook with it Good safety pro le a ADI 50 mgkg body weight b 80 packetsday 14 diet sodas 7 FDA has attributed side effects to a small population like headaches dizziness nausea and seizures xi Sucralose 1 Ex Splenda 2 600x sweeter than sucrose 3 The only sweetener made from sucrose a Sucrose with 3 chlorines substituted for hydroxyl groups b This substitution prevents it from being digested and absorbed 4 Heat stable can cook with it 5 ADI 5 mgkg body weight day a 7 packetsday xii Stevia also called rebiana Ex Sweet Leaf Derived from plant South American herb No caloric intake 1503OOX sweeter than sucrose ADI 4 mgkg body weight FDA has only approved it in beverages a FDA issued letters of nonobjection for the use of a natural zerocalorie sweetener 5 Recommended carbohydrate intake a Recommendation 4565 of total energy b RDA 130 gday for adults i To prevent ketosis using fat for energy U1 P P FPUNI 6 Our carbohydrate intake a 50 of our total energy needs b Added sugars 145 of kcal i Recommended that added sugars account for only 6 of kcal dietary guidelines ii WHO states added sugars should account for only 10 of kcal iii Upper limit 25 of kcals from added sugars c US population consumes 36 of carbs as drinks d Dietary ber i 2550 less than recommended ii Average intake 1 1 fruit 2 1 of fewer whole grain servings iii Fiber recommendation 14g1000kcal is adequate intake 1 25gday women under 50 21 gd after 51 2 38gday men under 50 30 gd after 51 7 What to do a Choose foods and drinks with little or no added sugars i Water or milk instead of soda ii Fruits for desserts iii 100 fruit juice instead of fruit drinks b Make half plate of fruit and vegetables c Make half of grains whole 8 Functions of digestible carbohydrates a Supply energy i Immediately used for energy 1 6carbon glucose is broken down to ATP and carbon dioxide ii Surplus of glucose is stored as glycogen 1 Glycogen kept in the liver and used by the brain 2 Glycogen kept in the muscles is used for extensive exercise iii Excess glucose is converted to and stored as fat 1 Adipose tissue fat 2 More permanent and unlimited storage b Protein sparing i Carbohydrates are needed to spare proteinsquot prevent them from being used for energy 1 Protein is converted into glucose when carbohydrate levels are low carbohydrate de ciency and low carbohydrate diets like Atkins Diet 2 Gluconeogenesis production of glucose ii In the US people get suf cient protein that it does not need to be spared In other nations this is a more essential role of carbohydrates c Preventing ketosis i Carbohydrates are needed to prevent ketosis 1 Without carbohydrates a Insulin release decreases b Fat is metabolized for energy inef ciently into ketones c Ketones are acidic products of fat breakdown 2 Ketosis leads to dehydration loss of lean body mass electrolyte imbalances coma and death d Health bene ts of dietary ber i Bowel health in the colon and the large intestine 1 Insoluble ber attracts water to intestines a Promotes softer larger stool regularly b Stimulates peristalsis c Reduces hemorrhoids and diverticula 2 Soluble ber is metabolized by bacteria Metabolized into shortchain fatty acids Absorbed into the bloodstream Some soluble bers are prebiotics Enhances the health of large intestine cells e Soluble ber yields a small amount of calories f Found in oatmeal ii Obesity reduction 1 Contributes to satiety without yielding energy 2 Fibrous foods absorb water and expand in the GI tract iii Glucose control 1 Soluble ber slows glucose absorption and decreases insulin release from the pancreas 2 Adults with high ber diets are less likely to develop diabetes iv Reducing cholesterol absorption 1 Soluble ber inhibits the absorption of cholesterol and bile 2 Reduces blood cholesterol and the risk of heart disease 9 Carbohydrate digestion a Mouth 006m i Saliva contains amylase which breaks starch down to dextrin and maltose b Stomach i Acidic environment that inactivates salivary amylase ii No further starch digestion occurs c Small intestine i Amylase from the pancreas digests starch into maltose ii Maltase 1 Maltose l glucose glucose iii Sucrase 1 Sucrose l glucose fructose iv Lactase 1 Lactose l glucose galactose v Final products glucose fructose galactose vi Monosaccharides are absorbed across the intestinal wall into the blood vii Fiber is not broken down viii Absorptive cells 1 To absorb glucose and galactose a Active absorption uses a sodium pump b ATP is used to pump Na out of absorptive cells 2 To absorb fructose a Facilitated diffusion occurs using a carrier protein b No energy is used d Portal vein i Transports absorbed monosaccharides to liver 1 The liver can then a Convert fructose and galactose to glucose b Release monosaccharides back to the blood stream c Store monosaccharides as glycogen or fat 10 Health concerns related to carbohydrate intake a High ber diets i Very high ber diets gt506O grams can be harmful ii High ber and low uid can cause constipation hemorrhoids and blockage iii Risk of nutrient de ciency decrease absorption of certain minerals iv Inadequate diet and nutrient intake certain populations b High sugar diets i Children and teenagers consume most added sugars 1 Soda replaces milk 2 Sweetened baked goods replace whole grains ii Empty calories low nutrient density iii Dental caries decay 10 11 12 13 14 1 Bacteria produce acid from carbohydrates 2 Acid causes cavities iv If sugar provides excessive calories it will cause weight gain 1 Associated with chronic diseases 2 Dietary patterns are dif cult to break Lactose intolerance Decrease in lactase enzyme i Reduces lactose digestion ii Lactose is 1 Undigested and not absorbed 2 Metabolized by large intestinal bacteria 3 Causes gas bloating cramping discomfort Primary disease caused by no apparent reason genetics maybe Secondary disease comes from infections that cause diarrhea Glucose intoleranceregulation Hormonal regulation of blood glucose i Insulin 1 Increases glucose uptake by cells 2 Promotes glycogen synthesis 3 Net effect lowers blood glucose ii Glucagon 1 Promotes glycogen breakdown 2 Net effect raises blood glucose iii Epinephrine 1 Fight or ightquot response 2 Breakdown of glycogen 3 Net effect raises blood glucose Diabetes Type 1 diabetes i 5 of cases ii Caused by an autoimmune attack on the pancreas iii Moderate genetic predisposition iv Ketosis occurs Type 2 diabetes i 90 of cases ii Caused by insulin resistance iii Strong genetic predisposition iv Risk factors include obesity physical inactivity and ethnicity v Ketosis does not occur Other blood sugar disorders Metabolic syndrome group of factors that increase risk for type 2 diabetes and cardiovascular disease 11 b Hypoglycemia i Reactive hypoglycemia exaggerated insulin response after eating ii Fasting hypoglycemia low blood sugar after fasting more than 8 hours underlying health condition 15 Carbohydrate quality a Measure glycemic index blood glucose response to a given food compared to a standard glucose solution white bread i Problem with glycemic index GI based on unrealistic serving sizes ii In uenced by the amount of starch structure ber content processing physical structure temperature and other macronutrients protein and fat b Measure glycemic load better re ection of food s effect on blood glucose i Glycemic index of carb amount of carb in 1 serving 100 ii EX 1 Vanilla waters have a glycemic index of 77 2 Amount of carbohydrate 15 grams 3 77 15 100 4 Glycemic load 12 iii Effect of high glycemic load stimulates insulin release 1 Insulin increases a Level of blood triglycerides b LDL cholesterol c Fat synthesis d Risk of cardiovascular disease 2 Hunger returns more quickly 3 Decreased by a Not overeating high glycemic load foods b Combining low and high glycemic load foods
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'