fiber

Question 1

Pompe Disease

Answer 1

Autosomal recessive inheritance
• Due to an inborn lack of -1,4 glucosidase
(acid maltase), an enzyme which cleaves
1,4 and 1,6 -glycosidic linkages.
• Absence of this enzyme leads to an
accumulation of glycogen in lysosomes.
Organs affected by accumulation of glycogen
– skeletal muscles (mostly), CNS, heart, liver,
• leading to:
– bulky muscles including macroglossia (enlarged
tongue) and cardiomegaly (enlarged heart)
– hypotonia (loss of muscle tone) and muscle
weakness, including congestive heart failure
(from heart muscle weakness)

Question 2

McArdle Disease

Cori’s type V glycogenosis

Answer 2

Results from a defect in muscle glycogen phosphorylaseB
.
• More than 30 known mutations can produce the same
clinical picture (phenotype).
• In about half of patients, there is a single base change
(R49X) in which the codon for Arg becomes a stop codon,
resulting in a partially completed non-functional protein.
• The remaining mutations are a mixture of nonsense (stop
codons) and missense (changed amino acid) mutations
that result in incorrect folding and/or loss of catalytic
activity
Glycogen phosphorylase activity is lost.
Notice the difference between normal pattern dark
staining for phosphorylase (figure A) compared to the
lack of dark staining (except in a few blood vessels) in a
patient with McArdle disease (figure B).
Occasional vacuoles are filled with glycogen (asterisks
in figure C) since glycogen can not be broken down to
glucose.
During normal exercise, O2 can not be transported
to muscles cells fast enough. Thus, a stored
reserve of glucose (glycogen) is used as fuel.
• Since glycogen can not be broken down to glucose
in patients with McArdle disease, lactate does not
build up.
• After several minutes of exercise, patients
experience severe muscle pain, probably from
increased ADP.

Question 3

symptoms of mcardle disease

Answer 3

Symptoms:
- muscular pain
- fatigability
- muscle cramping following exercise, which
disappears with rest
- later in life - severe cramps and myoglobinuria
after exercise.
- kidney failure can be associated with
rhabdomyolysis (muscle breakdown)

limited ability to perform strenous exercise due to painful cramps

Question 4

what is fiber- health Canada

Answer 4

Health Canada Definition:
• non-digestible carbohydrate and lignin
(of plant origin)

Question 5

us/ cdn institute of medicine

Answer 5

U.S./Cdn Definition Institute of Medicine
‘Dietary Reference Intakes’ (2002):
Dietary Fiber: non-digestible carbohydrate and lignin that are
intrinsic and intact in plants.
Functional Fiber: isolated, non-digestible carbohydrate
that have beneficial effects in humans.
Total Fiber: sum of Dietary and Functional Fiber.

Question 6

functional fiber

Answer 6

Functional Fiber: isolated, non-digestible carbohydrate

that have beneficial effects in humans.

Question 7

dietary fiber

Answer 7

Dietary Fiber: non-digestible carbohydrate and lignin that are
intrinsic and intact in plants.

Question 8

fiber classification

Answer 8

soluble (viscos) and insoluble (non-viscous fiber)

Question 9

insoluble fiber

Answer 9

cellulose (β-[1,4]-linked glucose) wheat bran
some hemicelluloses (glucose, arabinose, mannose, xylose)
vegetables and fruit (associated with cellulose)
lignin (polyphenolics) all plant foods (‘woody’ plant cell walls)

Question 10

soluble fiber

Answer 10

some hemicelluloses (glucose, arabinose, mannose, xylose)
vegetables and fruit (associated with cellulose)
pectin (galacturonic acid and rhamnose) fruits and vegetables
gums (galactomannans–highly viscous) seeds
β-glucans (highly branched β-linked glucose) oats, barley

Question 11

effects of insoluble fiber

Answer 11

Slowly fermented - fecal bulking [laxation, colonic health, ulcerative
colitis, colon cancer]
e.g., wheat bran: fecal bulking 5.7 g / g bran
bulks it by 6 times

Question 12

soluble fiber

Answer 12

Fermented - produce short chain fatty acids
(butyrate, propionate, acetate) [colonic health, CHD?]
High Viscosity - increases bile acid excretion [CHD]
- slows carbohydrate absorption [diabetes, CHD]

Question 13

which fiber reduces cholestrol due to bile

Answer 13

soluble fiber- highly viscose

Question 14

which one decreases the glycemic index

Answer 14

the soluble fibers- slows absorption

Question 15

Glycemic Index / Glycemic Load

Answer 15

GI: the relative blood glucose response to
dietary CHO (compared to control food –
usually white bread or pure glucose)
• GL: takes into account the quality and
quality of CHO in a food. Calculated by
multiplying the glycemic index by the
amount of CHO in grams provided by a
food and dividing the total by 100

Question 16

why doesnt the red lone go down in soluble fiber

Answer 16

baby isnt responding to the insolin so its still being produced- still better than without the fiber

Question 17

Cardiovascular Disease, Canadian

Statistics (1999)

Answer 17

• Cardiovascular Deaths: 79,000 per year
• 35% of all deaths for men
• 38% of all deaths for women

• 48% of men & 43% of women have elevated
cholesterol
Health Agencies
First line of intervention to reduce cholesterol
and CHD risk is through lifestyle change
(diet, ↑physical activity, weight control)

Question 18

Cholesterol Reduction

Answer 18

↓ Cholesterol 1% = ↓ CHD 2%

Question 19

What is a Heart-Healthy Diet?Working Group on Hypercholesterolemia and Other
Dyslipidemias (Canadian):

Answer 19

Working Group on Hypercholesterolemia and Other
Dyslipidemias (Canadian):
• <30% total fat
• <10% saturated fat and trans fatty acids
• <300 mg/d dietary cholesterol
• 25-30 g/d fiber
• healthy whole foods (Canada’s Food Guide)
• whole grains (5-10 servings per day)
• fruit and vegetables (5-10 servings per day)
• low-fat milk products (2-4 servings per day)
• low-fat meat and alternatives (2-3 servings per day)

Question 20

“Portfolio Diet” – University of Toronto researchers- devines which fiber to have- the viscose fibers

Answer 20

Plant sterols (1.0 g/1000 kcal)
• Soy protein (22.5 g/1000 kcal)
• Viscous fibers (10 g/1000 kcal)
• Almonds (22.5 g/1000 kcal)

Question 21

National Cholesterol Education Program (Step III):

Answer 21

National Cholesterol Education Program (Step III):
• 25-35% total fat
• <7% saturated fat; <10% PUFA; <20% MUFA
• <200 mg dietary cholesterol
• 20-30 g/d fiber
• healthy whole foods (whole grains, fruit & vegetables)
• viscous (soluble) fiber (10-25 g/d)
• plant stanol/sterols (2 g/d

Question 22

What is a Heart-Healthy Diet?

American Heart Association:

Answer 22

• Balance calorie intake and physical activity to achieve or maintain a
healthy body weight
• Consume a diet rich in vegetables and fruits
• Choose whole-grain, high-fiber foods
• Consume fish, especially oily fish, at least twice a week
• Limit your intake of saturated fat to <7% of energy, trans fat to <1% of
energy, and cholesterol to <300 mg per day
• Minimize your intake of beverages and foods with added sugars
• Choose and prepare foods with little or no salt
• If you consume alcohol, do so in moderation

Question 23

Current FDA Health Claims

for CHD Risk Reduction

Answer 23

Vegetable Proteins
• Soy
Viscous Fibers Phytosterols
• Oat ß-glucan • Sterols
• Psyllium • Stanols
Nuts
 (under consideration)

Question 24

if you were 60kg and you only ate soy as a protein

Answer 24

10% decrease in t-chol, 13% decrease in LDL chol, 10% decrees in trig and a 2% increase in hdl

Question 25

what is in nuts that are so good for you

Answer 25

1. Viscous fibers = increase Bile acid loss
2. Soy Protein = decrease Cholesterol synthesis
   increase LDL receptor uptake
3. Phytosterols = decrease Cholesterol absorption

nuts contain alot of MUFA (increase in HDL and decrease in LDL)
its a vegetable (decrease LDL)
has vit e and phenolics (decrease )