Clinical Nutrition - Chapter 4

what is considered a high glycemic index?

70 and above

starch

A plant polysaccharide composed of glucose

high fructose corn syrup HFCS

A widely used commercial caloric sweetner made by adding enzymes to cornstarch to convert a portion of its glucose molecules into sweet tasting fructose.

acceptable daily intake

ADI - the estimated amount of a sweetener that individuals can safely consume each day over the course of a lifetime without adverse affect

granulated sugar

common table sugar crystalline sucrose 99.9% pure

polysaccharides

compounds composed of long strands of glucose units linked together - aka complex carbohydrates - glycogen, starches, fibers

confectioner's sugar

finely powdered sucrose 99.9% pure

viscous

having a gel-like consistency that flows relatively slowly.

how are disaccharides broken down?

hydrolysis

glucose

monosaccharide used in both plant and animal tissues for energy sometimes known as blood sugar or dextrose.

saccharin

no longer suspected of causing bladder cancer

dietary fibers

nonstarch polysaccharides that are not digested by human digestive enzymes although some are digested by resident bacteria of the colon - cellulose, hemicelluloses, pectins, gums, mucilages, and a few nonpolysaccharides such as lignin.

disaccharides

pairs of monosaccharides - glucose, fructose and galactose

resistant starches

starches that escape digestion and absorption in the small intestine of healthy people

honey

sugar formed from nectar gathered by bees

added sugars

sugars and syrups added to food for any purpose such as to add sweetness or bulk or to aid in browning baked goods. Also called carbohydrate sweeteners they include concentrated fruit juice glucose, fructose, high fructose corn syrup, sucrose, and other sweet carbohydrates

nutritive sweeteners

sweeteners that yield energy

gluconeogenesis

the creation of glucose from a noncarbohydrate source

raw sugars

the first crop of crystals harvested during sugar processing. Raw sugar cannot be sold in the United States because it contains too much filth. Sugar sold as "raw sugar" is actually evaporated cane juice.

how are carbohydrates digested?

1. pancreatic amylase enters small intestine via pancreatic duct and continues breaking down polysaccharides into glucose and maltose 2. in outer membranes of intestinal cells, specific enzymes break down specific disaccharides

what is considered a high glycemic load?

20 and above

what is considered a low glycemic index?

55 or less

sucrose

A disaccharide composed of glucose and fructose - refined from sugar cane and sugar beets - aka table, beet, or cane sugar and often as simply sugar.

turbinado sugar

sugar produced using the same refining process as white sugar, but without the bleaching and anti-caking treatment

artificial sweeteners

sugar substitutes that provide negligible, if any, energy

simple carbohydrates

sugars, monosaccharides and disaccharides

protein-sparing action

the action of carbohydrate (and fat) in providing energy that allows protein to be used for other purposes

fermentation

the anaerobic (without oxygen) breakdown of carbohydrates by microorganisms that releases small organic compounds along with carbon dioxide and energy.

glycemic response

the extent to which a food raises the blood glucose concentration and elicits an insulin response

satiety

the feeling of fullness and satisfaction that comes after a meal and inhibits eating until the next meal

lactase

the intestinal enzyme that splits the disaccharide lactose to monosaccharides during digestion.

what is considered a low glycemic load?

10 or less

sugar alcohols

"sugar replacers" evoke low glycemic response

glycemic load GL =

GI/100 * net carbs

glycogen

a highly branched polysaccharide that is made and stored by liver and muscle tissues as a storage form of glucose. Glycogen is not a significant food source of carbohydrate and is not counted as one of the complex carbohydrates in foods.

epinephrine

a hormone of the adrenal gland that modulates the stress response - formerly called adrenaline

insulin

a hormone secreted by the pancreas in response to increased blood glucose concentration. - primary role is to control the transport of glucose from the bloodstream into the muscle and fat cells

glucagon

a hormone secreted by the pancreas that stimulates the liver to release glucose into the blood when blood glucose concentration decreases.

glycemic index GI

a method of classifying foods according to their potential for raising blood glucose

fructose

a monosaccharide found in fruits, honey and saps - sweetest of the sugars - sometimes known as fruit sugar or levulose

corn syrup

a syrup made from cornstarch that has been treated with acid, high temps, and enzymes that produce glucose, maltose, and dextrose

high fructose corn syrup

a syrup made from cornstarch that has been treated with an enzyme that converts some of the glucose into the sweeter fructose - made especially for use in processed foods and beverages

phytic acid

accompanies grains, and binds minerals (zinc, iron, calcium) to form insoluble complexes that pass through the body unused

aspartame

aka Nutrasweet - an artificial sweetener composed of two amino acids, phenylalanine and aspartic acid

hypoglycemia

an abnormally low blood glucose concentration

amylase

an enzyme that breaks down starches, secreted by salivary glands

levulose

an older name for fructose.

ketosis

an undesirable high concentration of ketone bodies such as acetone in the blood and urine.

corn sweeteners

corn syrup and sugar solutions derived from corn.

dental caries

decay of the teeth.

what three simple sugars have the same chemical formula, but different structures?

glucose, fructose, galactose C₆H₁₂O₆

white sugar

granulated sucrose, produced by dissolving, concentrating and recrystallizing raw sugar. Also called table sugar.

lactose intolerance

impaired ability to digest lactose due to reduced amounts of the enzyme lactase - bloating, gas, abdominal discomfort, diarrhea

soluble fibers

indigestible food components that dissolve in water to form a gel. - fruit pectin

insoluble fibers

indigestible food components that do not dissolve in water - tough fibrous structures of fruits, vegetables, and grains - celery

complex carbohydrates

long chains of sugar units arranged to form starch or fiber polysaccharides

what is the desired glycemic respnse

low glycemic response = slow absorption, modes rise in blood glucose, and a smooth return to normal

what enzymes are active in the final stage of carbohydrate digestion?

maltase sucrase lactase

which organ performs most of the work of carbohydrate digestion?

small intestine

after cooking, _____ is highly digestible by humans

starch raw starch often resists digestion

ketone bodies

the product of the incomplete breakdown of fat when glucose is not available in the cells

molasses

the thick brown syrup produced during sugar refining

type 1 diabetes

the type of diabetes in which the pancreas fails to produce insulin - often diagnosed in childhood, although some cases arise in adulthood

type 2 diabetes

the type of diabetes in which the pancreas makes plenty of insulin but the body's cells fail to respond to it - often diagnosed in adulthood

brown sugar

white sugar with molasses added - 91% to 96% pure sucrose.

maple syrup

a concentrated solution of sucrose derived from the sap of the sugar maple tree

lactose

a diassacharide composed of glucose and galactase principal carbohydrate of milk - sometimes known as milk sugar

maltose

a disaccharide composed of two glucose units - produced when starch is broken down - sometimes known as malt sugar.

kefir

a fermented milk created by adding specific bacteria that break down lactose to glucose and galactose, producing a sweet, lactose-free product

invert sugar

a mixture of glucose and fructose formed by the hydrolysis of sucrose in a chemical process. - sold only in liquid form and sweeter than sucrose - used as a food additive to help preserve freshness and prevent shrinkage

galactose

a monosaccharide that is part of the disaccharide lactose

Carbohydrates

compounds composed of single or multiple sugars. Most carbs = (CH2O)n = "1-2-1"

how are disaccharides and polysaccharides formed?

condensation reaction