Carbohydrate Storage
and Disorders
By Jennifer Turley
and Joan Thompson
© 2013 Cengage
Presentation Overview
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STORAGE
DISORDERS
Blood Sugar (glucose) • Lactose Intolerance &
Starch vs. Glycogen
Lactose Mal-digestion
Glycogen in detail
• Hypoglycemia
Blood sugar regulation • Diabetes
• Insulin & Glucagon
What is Glucose Used for?
• Immediate carbohydrate energy &/or glycogen
storage (Liver & Muscle).
• Brain, central nervous system (CNS), & red
blood cell (RBC) function (liver glycogen).
– Requires a minimum of 100-150 grams carbohydrate day
(continuous).
• Muscle functioning (muscle glycogen).
• Fat synthesis (excess energy intake).
What is Glycogen?
• The storage form of glucose, “animal starch”.
• Made from dietary carbohydrate sources.
– All carbohydrate is converted to glucose then
stored as glycogen or used immediately.
Diets should be planned to meet the 45-65%
of Calories AMDR & minimally the DRI for
carbohydrate (130 gm/day for adults).
Where is Glycogen Stored?
• The Liver (100 grams; 400 Calories).
– Is used for blood sugar (glucose) regulation.
• The Muscle (1-4 grams/100 grams of muscle).
– The level increases with high carbohydrate diets &
exercise.
– Is used for the working muscle.
How Does the Body
Regulate Blood Sugar?
• By hormones that are produced in the
pancreas.
• The hormones effect the liver & muscle cells.
– Insulin: decreases blood sugar levels.
– Glucagon: increases blood sugar level.
Blood Sugar Regulation
Blood Sugar Regulation
Carbohydrate Related
Disorders
• Lactose Intolerance &
Lactose Mal-digestion
• Hypoglycemia
• Diabetes
Lactose Intolerance
Physiology:
• Lactase deficiency (completely missing in
“intolerance” while low activity/levels in “mal-digestion”)
is strongly tied to evolution with several gene
mutations identified.
• Symptoms: Gas, bloating, cramps, diarrhea.
Lactose
Intolerance
Dairy Products and
Lactose Intolerance
• Use a product like lactaid
• Consume yogurt with live
cultures
• Consume aged cheese
OR
• Avoid dairy products
Allergy vs. Intolerance
• Lactose intolerance & mal-digestion are
due to an inability to digest milk sugar
(lactose) not an allergic reaction to milk
protein (casein).
• An allergy elicits an immune reaction &
involves antigens & antibodies.
– Antibody: Protein structures produced by
immune cells that inactivate antigens
(allergens).
– Antigen (allergen): Foreign protein
substances that elicit an immune reaction.
• Allergic responses cause the formation
of mucous in the respiratory tract, GI
distress &/or hives.
Antibody and
Allergen in an
Allergic Immune
Response
Hypoglycemia
low blood sugar
• Reactive: Blood sugar levels drop after eating sugar.
– Too much insulin is secreted in response to sugar
consumption. Hyperinsulinemia.
• Spontaneous: Liver stores of glycogen are depleted, the
ability to maintain blood sugar is diminished.
– Happens to everyone in between meals or when food has
not been consumed. 4-6 hours during the day, 10-12 hours
with sleep.
• Drug Induced: Low blood sugar from a drug reaction.
– Improper insulin or oral hypoglycemic drug use with
diabetes.
– Anti-inflammatory and thyroid medications are
known to cause hypoglycemia.
Diabetes
A chronic disease
• Is characterized by hyperglycemia (high blood
sugar).
• Affects >20 million Americans, many unaware.
• Increases heart disease, stroke, kidney disease,
retinopathy, and neuropathy.
• Decreases life expectancy.
• Occurs as type 1 or type 2
diabetes.
Type 1
Less common
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~5% of cases
Juvenile onset
Is more difficult to control
Insulin administration is essential in the control
of blood sugar (Insulin-dependent diabetes)
• Is due to a genetic and/or viral factor causing
auto immunity directed against the pancreatic
beta cells
Physiology of Type 1 Diabetes
Blood
Stream
1. Antibodies attack the
insulin producing
cells of the pancreas.
2. No insulin is made.
3. Blood glucose/sugar
levels are high.
4. Liver & muscle cells
cannot take up
glucose because
there is no insulin to
bind the cell
receptor.
Physiology of Type 1 Diabetes
Blood
Stream
Insulin is injected
into soft tissue &
works its way into
the blood stream
5. Insulin is injected.
6. The insulin receptor on
liver and muscle cells
bind to insulin &
take up glucose.
7. Blood sugar levels decline.
Type 2
Very common
• ~95% of cases
• Typically adult onset
• May be controlled with lifestyle changes
& oral hypoglycemic agents
• Is caused by insulin resistance (decreased
insulin receptor response)
• Is predisposed by obesity & genetics.
Physiology of Type 2 Diabetes
Blood
Stream
1. The pancreas produces
insulin.
2. Blood glucose/sugar
levels are high.
3. The insulin receptor
on the liver and muscle
cells are insensitive to
the insulin.
Physiology of Type 2 Diabetes
Drug pill is taken
orally & works it’s
way into the blood
stream
Blood
Stream
Drug
1. Oral Hypoglycemic
drugs are used to make
the cells respond to the
insulin.
2. Blood sugar levels decline.
Indications of Diabetes
• Fasting glucose level ≥ 126 mg/dl.
• 2 hour post prandial (fed) blood glucose
level ≥ 200 mg/dl.
Normal Blood Glucose is 70-99 mg/dl
Pre-Diabetes is 100-125 mg/dl
Glucose Tolerance Test
Measures Carbohydrate Metabolism
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Normal diet for 3 days prior to test.
Baseline fasting blood sugar level. (Levels ≥126 mg/dl indicate diabetes).
Glucose load. 1 gm carbohydrate /Kg body weight or a max of 100 gm
for adults.
Monitor blood sugar every half hour for six hours.
Overweight
Contributes to
Hyperglycemia
type 2 diabetes
Case Studies: Dick & Jane
DICK
JANE
300
250
200
Dick's Blood
Sugar (mg/dl)
Dick's Weight (lbs)
150
100
50
0
-12
-9
-6
-3
0
months
Dick’s blood sugar dropped from >600
mg/dl to 90-100 mg/dl over 12 months
with weight loss from 262 to 233 lbs.
months
Jane’s blood sugar went up from 128 mg/dl to
240 mg/dl after gaining an extra 10lbs. Over 24
months she gradually lost 100 lbs and brought
her blood sugar to normal.
Food Composition
The Glycemic Response/Index
• Simple sugars & foods with a high
glycemic index burn up fast & elicit an
insulin response.
• Complex carbohydrates sustain energy
better.
What is the
Glycemic Response/Index?
• The rise in blood sugar in response to
food as compared to glucose.
• Glucose is assigned 100.
• The Glycemic Index of a food can be
useful to anyone concerned with
blood sugar control.
Glycemic Response of Foods
• Those with diabetes should eat foods
that have a lower glycemic response or
slower entrance of glucose into the blood
stream.
• Foods with high protein, fat, & fiber lower
the glycemic response.
Glycemic Index of Foods
Summary
• Glucose is required by the brain, RBCs & CNS
for energy (ATP).
• Carbohydrate is the preferred energy source
of the body.
• All carbohydrate is converted to glucose for
energy.
• Excess carbohydrate is stored as glycogen.
(liver & muscle)
• If glycogen stores are full, excess
carbohydrate is stored as fat.
Summary
• Liver glycogen maintains blood sugar
for brain, RBCs & CNS function.
• Muscle glycogen maintains the
working muscle in high intensity
exercise.
• The hormones insulin & glucagon
regulate blood sugar levels.
• Insulin decreases while glucagon
increases blood sugar.
Summary
• Lactose intolerance occurs when the enzyme
lactase is missing.
• Milk allergy involves immunity.
• Hypoglycemia is low blood sugar. Can be
reactive, spontaneous, or drug induced.
• Hyperglycemia is a sign of diabetes.
Summary
• Diabetes occurs as type 1 & type 2.
• Unmanaged diabetes has health implications.
• Individuals with diabetes should consider the
glycemic response of foods for diet planning.
• Selecting low glycemic index foods is useful in
controlling blood sugar rises.
References for this presentation are the same as
those for this topic found in module 3 of the textbook