Chapter 4: Carbohydrates: Sugars, Starches and Fibers
Fermentable
The extent to which bacteria in the GI tract can break down fibers to fragments that the body can use
Type 1 Diabetes
The less common type of diabetes in which the pancreas produces little or no insulin - referred to as childhood-onset diabetes because it is often precipitated by genetic issues that are present in birth -given to young children
Gluconeogenesis
The making of glucose from a noncarbohydrate source, converts protein to glucose
Type 2 Diabetes
The more common type of diabetes when the pancreas secretes insulin but it's not enough and it's not affective -preventable -common in overweight or obese children & adults
glycogenolysis
The process of converting excess glucose into glycogen in your liver and muscle.
endosperm
The starchy part of the grain kernel.
How many grams a day of carbohydrates do you need to prevent ketosis?
50-100 grams a day of carbohydrates
Maltose
A disaccharide composed of two glucose units; sometimes known as malt sugar present in barley and malted grains (glucose + glucose)
fiber
A form of complex carbohydrates from plants that humans cannot digest A nondigestible polysaccharide.
Epinephrine
A hormone of the adrenal gland that modulates the stress response -aka adrenaline -signals the liver cells to release glucose - "fight-or-flight" hormone -used when stress, bleeding, low blood glucose levels trigger its release
Glycemic Index
A method of classifying foods according to their potential for raising blood glucose -, how quickly the glucose is absorbed after a person eats, how high the blood glucose rises, and how quickly it returns to normal. - selecting foods with a low glycemic index is a practical way to improve glucose control and lower the risk of diabetes.
Galactose
A monosaccharide; part of the disaccharide lactose least sweet of the sugars found in few food (sugar beets, some dairy)
3 types of alternative sweeteners
artificial sweeteners, other high-intensity sweeteners, and sugar alcohols.
Dietary fiber is found is good amounts in four of the following foods except one. What food has the lowest amount of dietary fiber? a. apples b. chicken breasts c. whole-wheat crackers d. carrots e. beans
b
Which of these items is not an "added sugar"? a. nectar b. cinnamon c. corn syrup d. molasses e. tagatose
b
Insulin moves glucose from _____ into _______
blood , cells
A typical serving of fruits contains an average of about _____. a. 20 grams of carbohydrates b. 30 grams of carbohydrates c. 15 grams of carbohydrates d. 10 grams of carbohydrates e. 6 grams of carbohydrates
c
Total fiber refers to the sum of ________ . a. dietary and viscous fibers b. functional and viscous fibers c. dietary and functional fibers d. insoluble fibers and starch e. starch and cellulose
c. dietary and functional fibers
all carbohydrates are composed of
carbon, hydrogen, oxygen
Which of the following statements is not true about carbohydrate structures? . Lactose is a disaccharide composed of glucose linked to galactose. b. Complex carbohydrates are polysaccharides consisting of many glucose units joined together. c. Simple carbohydrates include monosaccharides and disaccharides. d. Sucrose is a disaccharide composed of glucose linked to galactose. e. Maltose is a disaccharide composed of glucose linked to glucose.
d Sucrose is a disaccharide composed of glucose linked to fructose, not galactose.
Low FODMAP diets often are used to treat which condition? a. hypoglycemia b. lactose intolerance c. type 1 diabetes d. irritable bowel syndrome e. type 2 diabete
d triggering digestive symptoms like bloating, gas and stomach pai
Which of the following compounds is produced by the liver during the breakdown of fat when carbohydrates are not available? a. insulin b. gastric acids c. glucagon d. beta cells e. ketone bodies
e
legumes is example of what type of carbohydrate and why? good or bad source of fiber?
example of a complex carbohydrate that will increase blood sugar levels slowly because it is comprised of polysaccharides good source of fiber
Most lactose-intolerant people cannot consume any products that might contain lactose. true or false
false
People on strict lactose-free diets need to read labels and avoid foods with four of the following ingredients except one. Which is an acceptable food for this diet? a. whey b. gluten c. milk solids d. milk e. casein
gluten
What is the process of the liver storing glucose as glycogen known as...?
glycogenesis
The pancreas secretes _____ and ______
insulin and glucagon
what 2 hormones regulate Blood glucose homeostasis or brings glucose from storage?
insulin, which moves glucose from the blood into the cells, and glucagon, which brings glucose out of storage when needed.
honey is example of what type of carbohydrate and why? good or bad source of fiber?
is an example of a simple carbohydrate that will increase blood sugar levels quickly because it is comprised of monosaccharides poor source of fiber
What are two roles of fiber in the stomach...?
it delays gastric emptying & creates a feeling of satiety (sah-TIE-eh-tee)
What is the role of the pancreas in breaking down carbohydrates?
it produces pancreatic amylase that is released into the small intestine via the pancreatic duct
What role does epinephrine have in blood glucose levels?
it stimulates glycogenolysis and increases blood glucose levels
Why can it be bad for the body to use fat as energy...?
ketone bodies form and cause ketosis
in carb digestion, what final three enzymes break carbohydrate disaccharides into monosaccharides...?
lactase, maltase, & sucrase
Fructose and galactose are mostly metabolized in which organ? a. kidney b. small intestine c. liver d. stomach e. gallbladder
liver
What causes lactose intolerance?
low levels of the enzyme lactase. - Lactase activity declines with age, diseases, drug use -remains undigested in intestine, which attracts water
3 disaccharide enzymes
maltase, lactase, sucrase
How are carbohydrates broken down in the mouth?
mastication mixes food with saliva. Salivary amylase enzyme breaks down amylose and amylopectin into smaller chains of carbohydrates.
What role does the small intestine play in the digestion/absorption of carbohydrates?
most carbohydrate digestion occur here Pancreatic amylase breaks down the amylose and amylopectin and small chains of carbohydrates into maltose, a disaccharide. *Brush border enzymes break down all disaccharides into the monosaccharides glucose, fructose, and galactose, which are absorbed into the bloodstream.
how much and who in the population is affected by Lactose Intolerance? symptoms
Affects 70% population Elderly, Asians, African Americans, Scandinavians & Northern Europeans Symptoms: gas, cramps, diarrhea, bloating, abdominal pain
Hypoglycemia
An abnormally low blood glucose sugar / concentration -blood glucose rises after eating and then gradually falls back into the normal range
Amylase
An enzyme that hydrolyzes amyloe
Ketosis and what does it disturb?
An undesirably high concentration of ketone bodies in blood and urine, disturbs acid-base balance
Carbohydrates
Compounds composed of carbon, oxygen and hydrogen arranged as monosaccharides or multiples of monosaccharides; most have a ratio of one carbon molecule to one water molecule
Polysaccharides
Compounds composed of many monosaccharides linked together 3 types: glycogen, starches, and fibers.
What links two monosaccharides together?
Condensation
What breaks down carbohydrates, specifically starch, in the mouth...?
salivary amylase
Where does nutrient absorption of Glucose and galactose take place and how?
small intestine by Active Transport
Ketone bodies are an alternative food source during _______
starvation
saccharide means
sugar
added sugar
sugars added to foods during processing or preparation
Lactase
Enzyme that hydrolyzes lactose
Maltase
Enzyme that hydrolyzes maltose
Sucrase
Enzyme that hydrolyzes sucrose
What role does the liver play in the digestion/absorption of carbohydrates?
Glucose is taken up by it from the blood. Most glucose is returned to the blood to be picked up and used by the body cells, or the body can use glucose for energy, convert it to glycogen, or store it as fat.
Stevia is an ________ and generally recognized as ____
Herbal product , safe
What breaks a disaccharide in two?
Hydrolysis
When is lactase the highest?
Immediately after birth It declines with age
germ
In grains, the seed of the grain kernel.
What does pancreatic amylase do and where?
In the small intestine, it breaks down remaining starch into maltose
how to treat lactose intolerance
Individualize diet Gradually add dairy products to your diet Use of fluid milk restricted Moderate use yogurt, cheese. Eat dairy foods with a meal or snack Acidophilus milk, Lactaid Milk and Lactaid milk products or soy milk Eat smaller amounts throughout day rather than large amount at one time Consume lactase pills with lactose-laden meals or snacks
what are the carbohydrates in the carbohydrates family?
Monosaccharides: single sugars Disaccharides: pairs of monosaccharides Polysaccharides: chains of monosaccharides
Sugars
Simple carbohydrates composed of monosaccharides or disaccharides
grains
1 ounce of this provides about 15 g of carbohydrates
when is insulin and glucagon released?
Blood sugar is high Blood sugar is low
Resistant starches
Starches that escape from digestion and absorbtion in the small intestine of healthy people
High-Intensity Sweeteners
Stevia leaves and monk fruit
Artificial sweeteners
Sugar substitutes that provide negligible, if any, energy give foods a sweet flavor without adding extra kcalories; they are sometimes called nonnutritive sweeteners
Health Effects of Added Sugar
sugars and syrups that are added to food during processing or preparation Sugar & obesity. - 1/2 of all added sugar from soft drinks & fruit drinks (2013) - Americans average 475 kcal/day added sugar (30 tsp) 2. Sugar & heart disease. - High sugar intake associated with higher TG levels and lower HDL 3. Sugar & diabetes. - May increase risk. - 300,000 drinking 1-2 sodas/day = 26% more likely diabetes, 2010 study. 4. Sugar contributes to dental caries. - How often and how much 5. Sugar contributes empty kcalories to the diet
How are carbohydrates broken down in the stomach?
the HCL acidity of the stomach inactivates the salivary amylase enzyme; thus very little digestion of carbohydrates occurs in the stomach
Glucagon
-- Glucagon is a hormone secreted by the pancreas when blood glucose falls. A hormone secreted by pancreas in response to low blood glucose concentration; - signals the liver cells to break down a polysaccharide molecule called glycogen into smaller molecules of glucose, which increases the level of glucose in the blood. alpha pancreatic cell
Insulin
-Insulin is a hormone secreted by the pancreas as blood glucose rises. A hormone released by the pancreas in response to elevated/high blood glucose concentration; controls the transport of glucose from the bloodstream into the muscle and fat cells -signals the cells of the body to absorb and store glucose, which decreases the level of glucose in the blood. -Directs conversion of glucose in excess of immediate energy needs into glycogen (glycogenesis) in liver and muscle cells (limited capacity) -will Decreases blood glucose beta pancreatic cell
Glycogen
-The storage form of glucose in humans and animals. stored in the liver and muscles An animal polysaccharide composed of glucose; a storage form of glucose manufactured and stored in the liver and muscles; not a significant food source of carbohydrate and is not counted as a dietary carbohydrate in foods contains hundreds of glucose units in highly branched chains
Disaccharides
-all disaccharides are pairs of monosaccharides two sugar units -glucose is present in all disaccharides -3 major disaccharides: sucrose, maltose, lactose
Glucose
-monosaccharide -blood sugar -main energy source for the body -part of every disaccharide
Monosaccharides , 3 examples
-single sugars / simple carbs, one unit. single ring C6H12O6 a. Glucose b. Galactose c. Fructose
Negative Health Effects of Fiber
1. Bulk effect may prevent adequate kcalorie intake 2. Abdominal discomfort 3. May interfere with mineral absorption
Functions of Carbohydrates
1. Primary energy source. 4/kcal/g 2. Secondary energy storage - glycogen. 3. Helps prevent ketosis from incomplete fat oxidation. 4. Spares protein for energy use 5. Maintains glucose homeostasis 6. Excess stored at fat. 7. Fiber promotes healthy digestive system function.
How much fiber to most americans get daily?
15 grams per day
About 15 percent of the average daily energy intake comes from concentrated sugars that have been refined and added to foods.
15%
The Dietary Guidelines for Americans recommends that consumers limit their daily intake of added sugars to 10 percent or less of total kcalories. On a 2000-calorie diet, how many calories from added sugar would this be?
200
What is the dietary reference intake for carbohydrates?
45 to 65 percent of energy requirement
What are complex carbohydrates? and what are they know as
A category of carbohydrates that contains many sugar units combined. much larger molecules comprised of hundreds to thousands of monosaccharides. - Since organisms need to break polysaccharides down into monosaccharides before they can enter the bloodstream, digestion and absorption are much slower, which delays the entry of sugar into the blood polysaccharides exs: - Starches - Glycogen - Fiber, cellulose
Hydrolysis
A chemical reaction in which one molecule is split into two molecules, with hydrogen added to one and a hydroxyl group to the other -breaks a disaccharide in two
Condensation
A chemical reaction in which water is released as two molecules combine to form one larger product -links two monosaccharides together
Diabetes
A chronic disorder of carbohydrate metabolism, usually resulting from insufficient or ineffective insulin
Lactose intolerance
A condition that results from the inability to digest the milk sugar lactose; characterized by bloating, gas, abdominal discomfort and diarrhea; differs from a milk allergy
Sucrose
A disaccharide composed of glucose and fructose; Sucrose is the sweetest of the disaccharides present in many fruits and some vegetables and grains commonly known as table sugar, beet sugar, or cane sugar (glucose + fructose)
Lactose
A disaccharide composed of glucose and galactose; commonly known as milk sugar main carbohydrate in milk (glucose + galactose)
Viscous
A gel-like consistency
Lactase deficiency
A lack of the enzyme required to digest the disaccharide lactose into its component monosaccharides
Fructose
A monosaccharide; sometimes known as fruit sugar or levulose -found abundantly in fruits, honey, and saps -sweetest of the sugars
Phytic acid
A non-nutrient component of plant seeds; also called phytate; Phytic acid occurs in the husks of grains, legumes, and seeds and is capable of binding materials in insoluble complexes in the intestine, which the body excretes unused
Where does nutrient absorption of fructose take place and how?
Facilitated Diffusion
True or False Lactose intolerance is the same as a milk allergy
False Lactose intolerance is different than a milk allergy
What foods take the longest and shortest time to digest?
Fats are the most difficult and take the greatest amount of time to digest. Simple carbohydrates are the fastest to be digested.
Positive Health Effects of Fiber
May protect against heart disease/stoke a. Blood pressure b. Improve lipid profiles ( cholesterol) c. inflammation 2. Weight management 3. May prevent colon cancer. 4. Helps control glycemic response. 5. Decrease in diverticular disease & decline in hemorrhoids.
Soluble fibers
Nonstarch polysaccharides that dissolve in water to form a gel -found in oats, barley, legumes, and citrus fruits (apples, citrus, grapes) -fermented by intestinal bacteria.
Insoluble fibers
Nonstarch polysaccharides that do not dissolve in water -not fermented by intestinal bacteria. -promote bowel movements, alleviate constipation -found in whole grains (bran) and vegetables -wheat brand, whole-grain cereal, vegetables, corn bran
Dietary fibers
Nonstarch polysaccharides that the body cannot digest and use for energy -found in all plant derived foods-vegetables, fruits, whole grains, and legumes. -most are polysaccharides
_______(organ) secretes _______(hormone) to make sure _______ goes into cells and that _______ goes into liver. If there is still more ______ after it's been stored, the excess will be converted to ____ and stored for later.
Pancreas Insulin Glucose Glycogen Glucose Fat
Starches
Plant polysaccharides composed of many glucose molecules lined together in branched chains (amylopectin) or unbranched chains (amylose). -plant cells store glucose as starches - Grains are the richest food source of starch
Sugar alcohols
Sugarlike compounds that can be derived from fruits or commercially produced from dextrose; absorbed more slowly than other sugars and metabolized differently in the human body; - not readily utilized by ordinary mouth bacteria -sugar-free" or reduced-kcalorie products referred as nutritive sweeteners. -provides kclaories
Nutritive sweetener
Sweeteners that yield energy
Nonnutritive sweeteners
Sweeteners that yield no energy (or insignificant energy)
What is the recommended dietary allowance RDA for carbohydrates?
The DRI says 130 grams per day for brain function
How much fiber is recommended
The DRI says 14 grams per 1000 calories to promote heart health so 28 grams of fiber for 2000 diet -% DV = 25 g - AI 38 g for men; AI 25 g for women -Three or more servings whole grain
Protein-sparing action
The action of carbohydrate in providing energy that allows protein to be used for other purposes
Acid-base balance
The equilibrium in the body between acid and bace concentrations
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 effect
Glycemic response
The extent to which a food raises the blood glucose concentration and elicits an insulin response -refers to how quickly glucose is absorbed after a person eats, how high blood glucose rises, and how quickly it returns to normal.
Satiety
The feeling of fullness and satisfaction that occurs after a meal and inhibits eating until the next meal
bran
The indigestible outer shell of the grain kernel.
What are "simple carbohydrates"...? and what are they know as
a category of carbohydrates that contain a single sugar unit one or two sugar molecules. Because of this, they are digested and absorbed rapidly, thus entering the bloodstream and increasing blood sugar levels quickly. Foods that contain many simple sugars are generally those devoid of complex molecules, such as fiber or starch. An example of a simple carbohydrate is honey. monosaccharides and disaccharides ; sugars
salivary amylase
a digestive enzyme that begins breaking down carbohydrate (starch) in the mouth; other important enzymes during carb digestion include panreatic amylase, maltase, sucrase, and lactase
How is glycogen typically stored in the body? a. 100 percent in muscle cells b. 1/2 in the muscle cells, 1/4 in the peripheral tissues, and 1/4 in the stomach c. 1/2 in the liver and 1/2 in the muscle cells d. 1/4 in the liver and 3/4 in the muscle cells e. 3/4 in muscle tissue and 1/4 in brain tissu
d. 1/4 in the liver and 3/4 in the muscle cells
Storage forms of glucose in living things include _____.
e. glycogen and starch
The action of bacterial enzymes on fiber in the large intestine results in the _____. a. release of small amounts of polysaccharides b. delay of gastric emptying c. release of acid secretions d. release of amylase e. release of short-chain fatty acids
e. release of short-chain fatty acids
What three things can the liver do with glucose...?
use it, store it as glycogen, or store it as fat
Ketone bodies
when there is no glucose available in the cells, because fat can't be broken down completely produced in the liver
What leads to the productions of ketone bodies?
when there is no glucose, because fat can't be broken down completely