Chapter 4 Carbohydrates 2 PDF

PHCP BSN 1A SEPTEMBER 25, 2024 TUESDAY ROOM 216 THE CARBOHYDRATES: Sugars, Starches & Fibers  Carbohydrates (CH2O)n Simple carbohydrates – Monosaccharides (single sugars) – Disaccharides (double sugars) Complex carbohydrates – Polysaccharides (many sugars...

PHCP BSN 1A SEPTEMBER 25, 2024 TUESDAY ROOM 216 THE CARBOHYDRATES: Sugars, Starches & Fibers  Carbohydrates (CH2O)n Simple carbohydrates – Monosaccharides (single sugars) – Disaccharides (double sugars) Complex carbohydrates – Polysaccharides (many sugars) Copyright 2005 Wadsworth Group, a division of Thomson Learning Simple Carbohydrates Monosaccharides (C6H12O6) Glucose Fructose Galactose Copyright 2005 Wadsworth Group, a division of Thomson Learning  Monosaccharides Glucose – dextrose or blood sugar 1. Primary fuel for the body 2. Found in all disaccharides & polysaccharides  Monosaccharides Fructose – fruit sugar 1. Found in fruit, honey, syrup 2. Converts to glucose in the body  Monosaccharides Galactose – part of lactose 1. Found in milk 2. Converts to glucose in the body Simple Carbohydrates Disaccharides Maltose Sucrose Lactose Copyright 2005 Wadsworth Group, a division of Thomson Learning  Disaccharides Sucrose – table sugar 1. Glucose + Fructose 2. Refined from sugar beets & cane  Disaccharides Lactose – milk sugar 1. Glucose + Galactose 2. Lactose intolerance – missing digestive enzyme needed to split into two monodisaccharide parts to absorb it  Disaccharides Maltose – malt sugar 1. Glucose + Glucose 2. Found in germinating seeds & used in fermentation to produce malted beverages (beer, whiskey) Condensation Hydrolysis Complex Carbohydrates Polysaccharides Glycogen Starches Fibers Copyright 2005 Wadsworth Group, a division of Thomson Learning  Polysaccharides Glycogen – long chains of glucose found in animals 1. Stored in liver & muscles 2. Helps maintain blood glucose and important source of “quick energy”, esp. during exercise (lasts only about 12 hrs)  Polysaccharides Starch – long chains of glucose found in plants 1. Cereal grains (wheat, rice, corn, etc.), legumes (beans & peas), and root vegetables (potatoes, yams)  Polysaccharides Fiber – mostly indigestible CHO; gums, mucilages, lignin 1. Component of plant cell walls 2. Classified according to solubility in water 3. Abundant in whole grains, legumes, fruits and vegetables  Fibers Insoluble – nonviscous; cellulose, lignins Soluble – viscous & fermentable; pectins, gums, mucilages  Digestion Mouth – Salivary amylase Stomach – Fibers and satiety Small Intestine -Maltase, sucrase, lactase  Digestion Pancreas – Pancreatic amylase Large Intestine -Fermentation of viscous fibers  Water, gas, short-chain fatty acid production Carbohydrate Digestion in the GI Tract Absorption  Metabolism Glucose in the Body Used for energy – fuels most of the body’s cells Stored as glycogen – 1/3 in the liver and 2/3 in muscles Made from protein – gluconeogenesis Converted to fat – when in excess of body’s needs  Constancy of Blood Glucose Regulating hormones – maintain glucose homeostasis 1. Insulin – moves glucose from the blood into cells 2. Glucagon – signals the liver to release glucose into the blood 3. Epinephrine – released when emergency fuel needed Maintaining Blood Glucose Homeostasis Constancy of Blood Glucose Diabetes – Type 1 diabetes Failure of insulin production – Type 2 diabetes Obesity Hypoglycemia – Rare in healthy people Glycemic response – Glycemic index Glycemic Index  Health Effects of Sugar Sugar in excess 1. Contains no nutrients and may contribute to malnutrition 2. Causes dental caries (tooth decay) 3. Does not cause, but can contribute to: obesity, diabetes, heart disease, & behavorial problems  Accusations Against Sugars Sugar causes obesity Sugar causes heart disease  Accusations Against Sugars Sugar causes misbehavior in children and criminal behavior in adults Sugar causes cravings and addictions – serotonin  Recommended Intakes of Sugars DRI – Dietary Reference Intake – No more than 25% of total daily energy intake -Limit added sugars to