Carbohydrates
Monosaccharides: Glucose
-Also known as dextrose -The form of carbohydrate to which all other forms are converted for eventual metabolism -Naturally found in berries, grapes, sweet corn, and corn syrup -Only fuel used by central nervous system, RBCs, and brain
Monosaccharides: Fructose
-Also known as levulose or fruit sugar -Found in ripe fruits and honey -Sweetest of all monosaccharides -used in soft drinks
Polysaccharides:
-Complex carbohydrates -Compounds of many monosaccharides -Important for nutrition: -Starch -Glycogen -Fiber
Disaccharides: Sucrose
-Composed of glucose and fructose -Form of carbohydrate present in granulated sugar, powdered sugar, brown sugar, and molasses -One of the sweetest and least expensive sugars Sources: -Sugar cane -Sugar beets -Sap of maple trees
Fiber: Insoluble
-Does not readily dissolve in water -E.g., cellulose, hemicellulose, and lignins
Digestion and Absorption: Disaccharides
-Enzymes sucrase, maltase, and lactase convert sucrose, maltose, and lactose to simple sugar glucose -Simple sugars absorbed directly into bloodstream -Glucose carried to cells
Polysaccharides: Starch
-Found in grains and vegetables -Storage form of glucose in plants -Supplies energy over longer period of time -Takes body longer to digest than monosaccharides or disaccharides
Disaccharides: Maltose
-Intermediary product in hydrolysis of starch -Also created during fermentation process that produces alcohol -Found in some infant formulas, malt beverage products, and beer -Not as sweet as glucose or sucrose
Metabolism
-Islets of Langerhans in pancreas secrete insulin -Hormone that controls glucose metabolism -Impaired or absent insulin secretion results in high blood glucose level -Hyperglycemia
Digestion and Absorption: Polysaccharides
-More complex -Digestibility varies -Cellulose wall broken down -Starch changed to intermediate product dextrin, then maltose, and finally glucose -Starch digestion begins in mouth where enzyme salivary amylase begins to change starch to dextrin
Disaccharides
-Pairs of monosaccharides -made of two of three sugars -Must be changed to simple sugars by hydrolysis before absorption -Sucrose, maltose, and lactose
Fiber: Soluble
-Partially dissolves in water -E.g., gums, pectins, some hemicellulose, and mucilages
Monosaccharides: Galactose
-Product of digestion of milk -Not found naturally -Source: Lactose- mild sugar
Digestion and Absorption: Monosaccharides
-Simple sugars absorbed directly into bloodstream -Carried to liver -Fructose and galactose changed to glucose -Glucose carried to cells
Disaccharides: Lactose
-Sugar found in milk -Distinct from other sugars -Not found in plants -Helps body absorb calcium -Not as sweet as monosaccharides or other disaccharides Lactose intolerance common -boating, abdominal cramps, diarrhea, gas
insoluble cellulose
-found in fruit and veggie skins -leaves -stems -promotes bowel regularity
Monosaccharides
-simple sugars -Simplest form of carbohydrates -Absorbed directly into bloodstream from small intestine -Glucose, fructose, and galactose cannot be reduced further
Ketoacidosis
When ketones are formed they accumulate in the blood, when this happens, we have a imbalance of acid and bases.
enriched grains
are when the vitamins are added back after being lost in processing
how many grams of carbs are you suppose to get a day
at least 50-100
soluble cellulose
beans -citris fruits -oat bran -helps decrease cholesterol -helps regulate blood sugar -lose weight
Symptoms of Lactose intolerance are
boating, abdominal cramps, diarrhea, gas
sources of polysaccharides starch
cereals, grains, potatos, corn, beans and yam
Major symptoms are of Ketoacidosis
coma and death
Carbs are the primary source of ________ for body.
energy
Ketones produced as byproduct of
fat metabolism
Minor symptoms are of Ketoacidosis
fatigue, nausea, lack of appetite
Cereal grains:
rice, wheat, pastas
Carbs should be _____% of our calories a day
50
Primary function of proteins:
Build and repair tissues
Waste Product of carbohydrates metabolism is
C02 and water
Fiber: Indigestible
Cannot be broken down by digestive enzymes
Named for chemical elements that compose them
Carbon (C) Hydrogen (H) Oxygen (O)
Principal sources of carbohydrates are plant foods
Cereal grains: Vegetables Fruits Sugars
Polysaccharides
Complex carbohydrates
1/2 day supply of energy is stored as
Glycogen
Carbohydrates stored for is
Glycogen
Impaired or absent insulin secretion results in high blood glucose level
Hyperglycemia
Low blood glucose level of < 70 mg per deciliter (dL) may occur with too much insulin or insufficient food intake
Hypoglycemia
Carbohydrates
Least expensive most abundant of energy nutrients Grow easily in most climates Easily digested
Fibers
Lower blood glucose levels May prevent some colon cancers Help prevent constipation, hemorrhoids, and diverticular disease by softening stool
Polysaccharides: Glycogen
-Also known as animal starch -Storage form of glucose in body -Hormone glucagon helps liver convert to glucose as needed -1/2 day supply of engery is stored as
Dietary fiber intake
20-35 g per day
Each gram of CHO provides __ calories
4
Classification of Carbs
Monosaccharides Disaccharides Polysaccharides
Functions of Carbohydrates are
Provide energy Spare protein Maintain normal fat metabolism Provide fiber
sources of polysaccharides glycogen
glucose stored in liver and muscle
Dietary fiber found in
grains, vegetables, and fruits
Vegetables
green leafy veggies, potatos, peas, lyma beans, beets
Fortified grains
is adding nutrients that have never been apart of the grain.
glucose + galactose =
lactose
Half-day's supply of carbohydrates stored in _____ and _______ for use as needed
liver and muscles
glucose + glucose =
maltose
Only substantial animal source
milk
glucose + fructose =
sucrose
If you increase fiber you must increase
water
sources of polysaccharides cellulose
wheat bran, whole grain cereals, fruits and green leafy veggie
hemicellulose
whole grain cereals
sources of polysaccharides hemicellulose
whole grains
lignins
woody parts of veggies, carrots and strawberry seeds
