Transcript Carbohydrates-1

CARBOHYDRATES-1
Lect-2
Sara AL-Mosharruf
OBJECTIVES
 Introduction
 Carbohydrates
classification
 Carbohydrate sources
 Recommended intakes of carbohydrates
 Function of carbohydrate
 Digestion , absorption and
lect-3
metabolism of carbohydrate
 Glucose in the body
lect-2
INTRODUCTION
Carbohydrates play a major role in our life and
make us healthy.
 Every cells of human body needs energy to do its
work.

People don't eat glucose directly, they eat
carbohydrates.
 Then
their
bodies
convert
the
carbohydrates into glucose for energy and to
glycogen for reserve energy.
 Dietary carbohydrate provided the body's great
source of fuel for energy.



The carbohydrates are compounds made of carbon
(C), oxygen (O) and hydrogen (H).
These atoms can form specified number of
chemical bonds, carbon form four bonds, oxygen
forms two and hydrogen forms one.

C
CARBOHYDRATES classification
Carbohydrate
Simple
Monosaccharide
& disaccharide
Ex. Sugars
Complex
Polysaccharide
Ex. Starch &fibers
Carbohydrate
Monosaccharaide
Single sugars
Glucose
Fructose
Galactose
Disaccharide
Polysaccharide
Double sugars
Multiple sugars
Sucrose
lactose
Maltose
Starch
MONOSACCHARIDE
 Most
of the monosaccharides important in
nutrition are hexoses.
 Monosaccharides
are the simplest form of
carbohydrate that can not broke down to
smaller units.
 The
three monosaccharides are important in
nutrition, all have the same number and
kinds of atoms(C6H12O6), but in different
arrangement.
The three kinds of monosaccharaides have
a different sweetness.
Glucose on the tongue gives a mildly sweet,
Galactose hardly tastes sweet at all, but
 Fructose is intensely sweet.

GLUCOSE
The basic single sugar in body
metabolism is glucose .
 Supply the primary fuel for cells .
 It is not usually found as such in
the diet.
 The body supply comes mainly
from the digestion of starch.
 It is also know as blood sugar or
dextrose.
 Glucose is one of the two
sugars in every disaccharide and
the unit from which the polysaccharides
are made almost exclusively.

FRUCTOSE

Fructose is the sweetest of the sugars.
Has the same chemical formula of glucose
but with different structure.


Fructose occurs naturally in fruits and honey.
The amount of fructose in fruits depends on
the degree of ripeness.



As the fruit ripens, some of the stored starch turns to
sugars.
It is also called fruit sugar.
GALACTOSE

Galactose occurs naturally as a
single sugar in only few foods.
Galactose has the same number
and kinds of atoms as glucose and
fructose in yet another arrangement.

Galactose also is not usually found as such
in the diet. But rather as a part of disaccharide
”lactose=glucose+galactose”

Milk is the primary food source of galactose.
Comes mainly from digestion of milk sugars (lactose).

DISACCHARIDES
Disaccharides: pairs of monosaccharides linked
together.
• Glucose occurs in all three, and the second member of
the pair is either fructose, galactose, or another
glucose.
• The CHO and all other energy nutrients
are
put
together
by
a
reaction
called
condensation(links two monosaccharaides together
and gives out water).
and are taken apart by reaction called hydrolysis (is
to break a disaccharide into two, and a molecule of
water splits to provide the H & OH needed to complete
the resulting monosaccharide). The hydrolysis often
occurs during digestion.
•
SUCROSE

Sucrose=glucose + fructose

Occurs naturally in fruits ,vegetables and grains.

To make a table sugar, sucrose is refined from the juices of
sugarance and sugar beets, then granulated.

Is common table sugar, and from sugar cane, sugar beets.


Depending to the extent to which it is refined ,the product
becomes the familiar brown, white, and powdered sugars
available in the grocery stores.
Sucrose is readily hydrolyzed by acids and by enzyme
sucrase in the small intestine into glucose and fructose.
LACTOSE
Lactose= glucose+ galactose
The principle CHO of milk .
Known as milk sugar.
The sugars derived primarily from plants, except for
lactose and its components galactose, which come from
milk and milk products.
Lactose is the only common sugar not found in plants.
It is less soluble and less sweet than sucrose.
Remains in the intestine longer than other sugar
encourage the growth of certain useful bacteria.
It is readily hydrolyses by enzyme lactase into
glucose and galactose.
MALTOSE
Maltose= glucose + glucose
The two single sugar units that composed maltose
are both glucose.
It is not usually found as such in the diet.
Maltose is
produce whenever starch is break down-it is derived
in the body from the intermediate
digestive
breakdown of starch.
occurs during the fermentation process that yields
alcohol.
 only a minor constituent of few food, most notably
barely.
POLYSACCHARIDES
Composed of many single sugar units linked
together.
• The important polysaccharides in nutrition
include starch, glycogen and dietary fiber.
•
STARCH
Starch: is long branches and unbranched chains of
hundred or thousands of glucose molecules linked
together.
 Is insoluble polysaccharide.
 Is the most dietary carbohydrates worldwide found in
grains(rice and wheat), legumes(peas and beans) and
tubers (potatoes and yams).
 When the plant is eaten, the body hydrolyzes the starch
to glucose.
 Moist and heat causes grains to swell, cell may disrupt
and the starch becomes soluble. Cooking renders the
starch to become soluble and more accessible to digestive
enzymes.
 Starch grains contains two polysaccharide derived from
glucose(amylose and amylopectin).




Because starch are more complex than simple
sugars, they breakdown more slowly and
supply energy over longer period of time.
Dextrin's are degradation product of starch in
which glucose chains have been broken down to
smaller units by partial hydrolysis.
The human body stores glucose as glycogen
But plant cells store glucose as starch.
GLYCOGEN

Is found only to a limited extent in meats and not at all in
plants.

The human body stores much of its glucose as glycogen and
it is found in the liver and muscles.

In storage many glucose molecules linked together in highly
branched chains. This arrangement permits rapid hydrolysis.


When the hormonal message arrives at the storage sites,
enzymes respond by attacking glycogen simultaneously,
making a surge of glucose available.
These small stores of glycogen help sustain normal blood
sugar during fasting and provide immediate fuel for
muscle action.
DIETARY FIBER
Dietary fibers are the structural parts of plants and thus
are found in all plants derived foods-vegetables, fruits,
whole grains ,and legumes.
Most dietary fibers are polysaccharides.
Fibers differ from starches in that the bonds between
their monosaccharaides cannot be broken down by
human digestive enzymes. (Non starch polysaccharide).
Fibers pass through the body and they contribute no
monosaccharide, and therefore little or no energy.
The bacteria of the gastrointestinal tract can break some
fibers down, this is important to digestion and health.
Dietary fibers into two groups

•
•
•
•
•
Soluble fiber:
Indigestible food components that dissolve in
water to form a gel(viscous).
Are easily digested by bacteria in the
colon(fermentable).
Commonly found in oats, barely, legumes, and
citrus fruit.
They are mostly associated with protecting
against heart disease and diabetes by lowering
blood cholesterol and glucose level,repectively.
An example is pectin from fruit, which is used to
thicken jellies.

•
•
•
•
Insoluble fiber:
Indigestible food components that do not dissolve
in water.
Don't form gels (nonviscous),and are less readily
fermented.
Found mainly in whole grains(bran),vegetables.
It promotes bowel movements and alleviate
constipation.
Types of fibers:
1- Cellulose: cellulose is the primary constituent of
plant cell wall . Occurs in all vegetables, fruits and
legumes.
2- Non-cellulose polysaccharides: such as pectin,
gums and mucilage.
3- Lignin: woody parts of vegetables such as
carrots and the small seeds of fruits (strawberries).
Total Fibers can be the sum of Dietary fibers
and Functional fibers .
Dietary fibers (all the previous).
Functional fibers : fibers usually occurs naturally
in plants when these fibers have been extracted
from plants or manufactured and then added to
foods or used in supplements.
Resistant starches:
 A few starches are classified as dietary fibers.
known as resistant starches, these starches
escape digestion and absorption in the small
intestine.
 Starch may resist digestion for several reasons,
including the individual efficiency in digesting
starches and the food physical properties.
 Resistant starch is common in whole legumes,
raw potatoes, and unripe banana.
Phytic acid
 It is not classified as dietary fiber, is often found
accompanying them in the same foods.
 The researchers have been unable to determine
whether it is dietary fiber, the phytic acid or
both, that binds with minerals, preventing their
absorption.
 This
binding presents a risk of mineral
deficiencies, but the risk is minimal when total
fiber intake is reasonable and mineral intake is
adequate.
Clinical importance of fibers:
1-Constipation
2-Colon cancer
3-Obesity
4-Hypoglycemia
5-Hyperglycemia
6-Diverticulosis
High fiber diet:
•
Is the dietary fibers exceed 40 gm/day.
•
Food sources: fruits, vegetables, bread & cereals.
Disadvantage of increasing fiber in the diet are:
1-Abdominal fullness
2-Increasing flatulence
3-Nausea and vomiting.
4-Gases
5-May interfere with mineral absorption.
6-More seriously can obstruct the GI tract.
•
CARBOHYDRATE
SOURCES
Table (1): Carbohydrate sources
Chemical class name
Class members
Sources
• Polysaccharides
(Multiple sugar or complex
carbohydrates)
• Starch
Grains and grains
products
Cereal, bread, pasta, rice,
corn, legumes, potatoes
and other vegetables.
•Glycogen
•Animal tissues, liver and
muscle meats.
•Dietary fiber
Whole grains, fruits,
Vegetables, seeds, nuts.
Chemical class name
Class members
Sources
Disaccharides ( Double
sugars, simple
carbohydrates)
•Sucrose
•Table sugar, sugar cane,
sugar beets, molasses.
• Lactose
•Milk.
• maltose
• Barley
•Glucose
Sweetener in food
products
Starch digestion, final
Corn syrup.
•Fructose
Fruits, honey.
• Galctose
Lactose (milk).
• Monosaccharide (single
sugars, simple
carbohydrate)
Recommended intakes of
carbohydrates
Dietary recommendations suggest that, CHO provide
more than half (55 to 60 %) of energy requirement.
 5-9 servings daily of combinations of fruits and
vegetables.
 6-11 servings daily of combination of breads, cereals
and legumes.
 The FDA (The Food and Drug Administration) set a
daily value on food for fibers at 25 gram fiber daily.
 The American Dietetic Association suggests that
20 - 25 grams of dietary fibers daily.


A high fiber diet is more than 40 gm/day.
CARBOHYDRATES-2
Lect-3
Sara AL-Mosharruf
OBJECTIVES
 Introduction
 Carbohydrates
classification
 Carbohydrate sources
 Recommended intakes of carbohydrates
 Function of carbohydrate
 Digestion , absorption and
lect-3
metabolism of carbohydrate
 Glucose in the body
lect-2
FUNCTIONS OF CARBOHYDRATES
1- Basic fuel supply



The main function of carbohydrate is to provide the
primary fuel.
Carbohydrates burn in the body at a rate of 4
kcal/gm.
Carbohydrates furnish readily available energy that
needed not only for physical activities but also for all
the work of the body cells.
2- Reserve fuel supply


The human body reserves carbohydrate as
glycogen (in liver an muscles).
Maintain a normal blood glucose level and to
prevent a breakdown of fat and protein in tissue.
People must eat carbohydrate foods regularly and
fairly frequent intervals to meet energy demand.

3- Special tissue functions

•
•
Liver:
glycogen reserves in the liver and muscle provide
constant exchange with the body's overall energy
balance system.
Reserves glycogen especially in the liver protect cell
from depressed metabolic function and resulting
injury.


•
•
Protein: in case of insufficient carbohydrate, the
human body use the protein as a fuel supply
which prevent protein to be used for its major
role in tissue growth and maintenance.
Fat:
Insufficient carbohydrate for energy, rapid
breakdown of fat would produce excess materials
called ketones, which result from incomplete fat
oxidation in the cell.
These ketones are acids, and can become serious.
4- Central nervous system
•
The brain has no stored supply of glucose,
therefore, it is dependent on a minute-to-minute
supply of glucose from the blood.
Sustained and profound shock from blood sugar
may cause brain damage.
•
5- Fibers
A. Cellulose
• Cellulose it remains undigested in the
gastrointestinal tract.
• And provide important bulk to the diet.
• This bulk helps
1 move the food mass along.
2 stimulate normal muscle action in the
intestine.
3and forms the feces for elimination of waste
products.
B. Noncellulose polysaccharides

Absorb water and swell to large bulk.

Slow the emptying of the food from the stomach .

Bind bile acids including cholesterol in the intestine.

Prevent spastic colon pressure by providing bulk for
normal muscle action.

Provide fermentation material for colon bacteria to
work on.
TABLE (2): SHOWN THAT, SUMMARY OF DIETARY
FIBER CLASSES
• Cellulose
•Noncellulose
polysaccharides
1- Gums, mucilage
and Seeds.
2- Algal polysaccharides
3- Pectin substances
Source
function
Main cell wall
constituent of
plants.
• Holds water.
• Reduces elevated
colonic intraluminal
pressure.
• Binds zinc.
• Secretions of
plants
• Algae.
• Intercellular
cement plant
material
• Slow gastric
emptying.
• Provides fermentable
material for colonic
bacteria with
production of gas and
volatile fatty
acids.
• Binds bile acids and
cholesterol
Source
4-Hemicellulose
•
Lignine
function
• Cell wall plant • Holds water and
Material.
increase stool bulk.
• reduces elevated
colonic pressure.
• binds bile acids
•Woody part of
plants
• Anioxidant.
• Binds bile acids,
cholesterol and metals.
DIGESTION ,
ABSORPTION AND
METABOLISM OF CARBOHYDRATE
The goal is to break sugar and starches into
small molecules-chiefly glucose-that the body can
absorb and use.
 A large starch molecule require extensive
breakdown.
The disaccharide needs only to be broken once.
And the monosaccharide not at all.
 The initial splitting begins in the mouth, and the
final splitting and absorption occur in small
intestine, and the conversion to common energy
(glucose) takes place in the liver.

CARBOHYDRATE DIGESTION
In the mouth:
Mastication: the process by which food is
crushed and ground by teeth .The chewing of
high-fiber food slows eating and stimulate the
flow of saliva.
Starch: salivary glands secretes
saliva into the mouth to moisten the food.
The salivary enzyme amylase begins
digestion.
Starch Amylase
small polyshcarrides,
maltose(disacharride)
Fibers: the mechanical action of the
mouth crushes and tears fiber in food
and mixes it with saliva to moisten
it for swallowing.
In the stomach:
Peristalsis: wave like muscular contraction.
The swallowed bolus(a portion of food swallowed at
one time) mixes with stomach acids and protein
digesting enzymes, which inactivate salivary amylase.
Starch: stomach acid inactivates salivary enzymes,
halting starch digestion.
To small extent ,the stomach acid continue breaking the
starch, but it juices contain no enzymes to digest CHO.
Fibers: is not digested in stomach and delays gastric
emptying thereby provide feeling of
fullness and
satiety.
In the small intestine :
In it most of the work of CHO digestion .
Starch: the pancreas produces an amylase that is
released through pancreatic duct into the small intestine.
The major CHO-digesting enzyme is the pancreatic
amylase which will continue breaking polysaccharides.
Starch
pancreatic amylase small polysaccharides,
maltoses
the pancreatic amylase in the duodenum breaks down
all small polysaccharides into disaccharides.
The final step takes place in the outer membrane of the
intestinal cells. The disaccharide digestion begins at this
point. There specific enzymes secreted from the intestinal
glands breaks down specific disaccharides.
The disaccharide enzymes on the surface of the small
intestinal cells hydrolyze the disaccharides into
monosaccharaides
Maltose maltase
Glucose +Glucose
Sucrose sucrase
Fructose+Glucose
Lactose lactase
Galactose+Glucose
==>intestinal cells absorb these monosaccharaides.
Fibers: is not digested ,and delays the absorption of other
nutrients.
Large intestine:
• Within 1-4 hours after a meal, all of the sugars and most of the
starches have been digested.
• Only fibers remain in the digestive tract.
• Fibers in large I. attracts water, which softens the stool for passage
without straining.
• Also, bacteria in the GI tract ferment some fibers.
• Most fiber passes intact through digestive tract to the large intestine.
Here, bacterial enzyme digest fiber.
Some fibers Bacterial Enzymes
short-chain
fatty acids, gas & water
• Colon uses these small fat molecules for energy. Metabolism of short
chain fatty acids occurs in the cells of liver. fiber therefore can
contribute some energy. Depending on the extent to which they are
broken down by bacteria an d the fatty acids are absorbed.
• Fiber holds water ,regulate bowel activity, and bind substances such
as bile ,cholesterol, and some minerals, carrying them out of the body.
CARBOHYDRATE ABSORPTION




Peristaltic movement moves the monosaccharaides into
the jejunum where digestion is completed and absorption
begins.
Absorption is increases as a result of the intestinal
villi(small mucus projections lining the small intestine).
Each villi contain blood capillary into which
the
monosaccharaides passes via diffusion or active transport.
Glucose is unique that it can be absorbed to some extent
through the lining of mouth, but for most part nutrient
absorption takes place in the small intestine.
Glucose and galactose traverse the cell lining the small
I. by active transport.


o
o
Fructose is absorbed by facilitated diffusion, which slows
its entry and produces a smaller rise in blood glucose.
Likewise, unbranced chains of starch are digested slowly
and produce
a smaller rise in blood glucose than
branched chains, which have many more places for
enzymes to attack and release glucose rapidly.
As the blood from the intestine circulates through the liver,
cells there take up fructose and galactose and convert
them to other compounds ,most often to glucose .
Thus all disaccharides provide at least one glucose
molecule directly ,and they can provide another one
indirectly –through the conversion of fructose and galactose
to glucose.
LACTOSE INTOLERANCE
A condition that results from inability to digest
the milk sugar lactose, characterized by bloating,
gas, abdominal discomfort, and diarrhea.
 Lactose intolerance differs than milk allergy,
which is caused by an immune reaction to the
protein in milk.
 It is a common condition that occurs when there
is insuffient lactase to digest the disaccharide
lactose found in milk and milk products.
 Because treatment requires limiting milk intake,
other sources of riboflavin, vitamin D , and
calcium must ne included in diet.

GALACTOSEMIA
Galactosemia (is a rare genetic metabolic disorder that
affects an individual's ability to metabolize the sugar
galactose properly. Although the sugar lactose can
metabolize to galactose, galactosemia is not related to and
should not be confused with lactose intolerance .
 Lactose in food (such as dairy products) is broken down by
the enzyme lactase into glucose and galactose.
 In individuals with galactosemia, the enzymes needed for
further metabolism of galactose are severely diminished
or missing entirely, leading to toxic levels of galactose 1phosphate in various tissues as in the case of classic
galactosemia,
resulting in hepatomegaly (an enlarged liver), cirrhosis,
renal failure, cataracts, brain damage, and ovarian failure.

CARBOHYDRATE METABOLISM








Glucose plays a central role in CHO metabolism.
Metabolism: is the sum of various chemical processes in
a living organism by which energy is made available for
the functioning of the whole organism.
Also includes building and breaking tissues.
Products of metabolism is called metabolite.
The cell is the functional unit of life in the humans.
Energy metabolism occurs in all cells to sustain life
process.
With the help of enzymes, glucose is chemically broken
down to produce energy.
Excess glucose maybe converted to fat and held in
reserve in adipose tissue.

•
•
•
Storing glucose as glycogen
The liver stores about 1/3 of the body’s total
glycogen and release glucose into the blood
stream as needed.
After a meal ,blood glucose rises, and liver cells
link the excess glucose molecules by condensation
reaction into long, branching chains of glycogen.
When blood Glucose falls liver cells breaks
glycogen by hydrolysis reactions into single
molecules of glucose and release them into blood
stream.
•
•
•
•
Thus glucose available to supply energy for brain and other
tissues regard less if person eat recently.
Muscle cells can also store glucose as glycogen (the two other
thirds),but they hoard most of their supply, using it just for
themselves during exercise. The brain maintain a small
amount of glycogen, which is thought to provide an emergency
energy reserve during times of severe glucose deprivation.
The body can store glycogen for only enough for short period of
time(less than a day for rest and few hours for most during
exercise).
For its long term energy reserves, for use of weeks or days of
deprivation, the body uses its abundant, water free fuel, fat.




Using glucose for energy
Glucose fuels the work of most of the body’s cells.
The liver glycogen stores last only 4 hrs, not for
days.
To keep glucose meeting energy needs, person
has to eat CHO frequently.





Making glucose from protein
Glucose is the preferred energy source for brain
cells, other nerve cells, and developing RBC.
Body protein can be concerted to glucose to some
extent. But proteins has jobs of its own that no
other can do it.
Body fat cannot be converted to glucose.
Thus if a person does not replenish depleted
glycogen stores by eating CHO ,body proteins are
broken down to make glucose to fuel these special
cells.


The conversion of protein to glucose is called
gluconeogensis (making of new glucose).
Only adequate dietary CHO can prevent this use
of protein for energy ,and this role of CHO is
known as its protein sparing action.




Making ketone bodies from fat fragments
An inadequate supply of CHO can shift the body's
energy metabolism in a precarious direction.
With less CHO providing glucose to meet the
brain energy needs, fat takes an alternative
metabolic pathway; instead if entering the main
energy pathway, fat fragments combine with
each other, forming ketone bodies.
Ketone bodies provide an alternate fuel source
during starvation, but when their production
exceeds their use, they accumulate in blood
,causing ketosis. A condition that disturbs body
normal acid-base balance.







Using glucose to make fat
After meeting the energy needs and filling its glycogen
stores to capacity, the body must find a way to handle
any extra glucose.
At first, energy metabolism shifts to use more glucose
instead of fat.
If that is not enough to restore glucose balance, the liver
breaks glucose into smaller molecules and put them
together into the more permanent energy storage
compound-fat.
Thus when CHO is abundant, fat is either conserved or
created.
The fat then travels to the fatty tissues of the body for
storage .
Unlike the liver cells, which can store only enough
glycogen to meet less than a day’s energy needs, fat cells
can store seemingly unlimited quantities of fat.
Metabolism
of CHO
Catabolism
-Glycogenlysis: the
catabolism of glycogen
-Oxidation of glucose and
synthesis of ATP.
Anabolism
Glycogenesis: synthesis
of glycogen in liver and
muscle .
GLUCOSE
IN THE BODY
Every body cell depends on glucose for its energy
to some extent, but the cells of the brain and the
rest of the nervous system depends almost
exclusively on glucose for energy.
The activities of these cells never stop, and they
have limited ability to store glucose.
Day and night, they continually draw on the
supply of glucose in the fluid supplying them.
To maintain the supply, a steady stream of blood
moves past these cells bringing more glucose
from either the intestine (food) or the liver(via
glycogen breakdown or gluconeogensis).
Maintaining glucose homeostasis:
To function optimally, the body must maintain
blood glucose within limits that permits the cells
to nourish themselves.
If blood glucose falls below normal, a person
may become dizzy and weak
If it rises above normal, a person become fatigue.
Left untreated fluctuation to the extremes-either
high or low-can be fatal.
:
 The regulating hormones
 Blood glucose homeostasis is regulated primarily
by two hormones:
Insulin: which move glucose from blood into cells
and
Glucagon: which brings glucose out of storage
when necessary.
 After a meal, as blood glucose rises, special cells
of pancreas respond by creating insulin into
blood.
 In general the amount of insulin secreted
corresponds with the rise of glucose.
 As the circulating insulin contacts the receptors
on the body's other cells, the receptors respond by
ushering glucose from the blood into the cells.
 Most of the cells takes only the glucose they can
use for energy right away, but the liver and
muscle cells can assemble the small glucose units
into glycogen for storage. The liver cells can also
convert glucose to fat for export to other cells.
 Thus elevated blood glucose returns to normal as
excess glucose is stored as glycogen and fat.





When blood glucose falls(as occurs between
meals),other special cells of pancreas respond by
secreting glucagon into blood.
Glucagon raises blood glucose by signaling the
liver to break down its glycogen stores and
release glucose into blood for use by all other
body cells.
It elicits release of glucose from liver glycogen.
Another hormone that signals liver cells to
release glucose is epinephrine.
Epinephrine :Is a hormone of the adrenal gland
that modulate the stress response, formally
called adrenaline.
Balance within normal range: (blood glucosefasting):
Normal: 70-120 mg/dl
Prediabetes: 100- 125 mg/dl
Diabetes: more or equal 126 mg/dl

Falling outside the normal range:
In some people, blood glucose regulation fails,
which results in either: diabetes or hypoglycemia.
Diabetes: is a chronic disorder of CHO
metabolism, usually resulting from insuffient or
ineffective insulin.
Type 1 DM: the less common type of DM in which
pancreas fails to produce insulin. The exact cause
is unclear(genetic or virus..)
Type 2 DM: the more common type of DM in
which the cells fail to respond to insulin. Usually
occurs as a result of obesity.
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Hypoglycemia: an abnormally low blood glucose
concentration.
Symptoms: weakness, rapid heartbeat ,sweating,
anxiety, hunger and trembling.
Usually it is a consequence of poorly managed
DM.
It is caused by too much insulin, strenuous
physical activity, inadequate food intake, or
illness that causes blood glucose to plummet.
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The glycemic response: the extent to which a food
raises the blood glucose concentration and elicit
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.
Low glycemic response is desirable and high
glycemic response is less desirable.
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Glycemic index: a method classifying food
according to their potential for raising blood
glucose.
 What
are source of blood glucose?
Either from:
1CHO sources
1-dietary CHO(high %)
2-glycogen
3-lactic acid and pyruvic acid
2Non-CHO sources
1-protein
2-fats