Transcript 4. Carbohydrates: simple and complex

Carbohydrates
And Type 2 Diabetes
1
Key Concepts and Facts
Simple sugars, starches, and dietary
fiber (cellulose)
 Poor diets are related to high sugar
intake
 Fiber benefits health
 Tooth decay is related to high sugar
intake

2
The Carbohydrates
The Major source of energy for people of the
world
 Main component of staples – bread, pasta,
rice, cassava, and beans
 We Americans consume 50% of total calories
as “carbs.” (Japanese, over 60%)
 Carbohydrate family has three types

– Simple sugars
– Complex carbohydrates (“starch”)
– Fiber (ie Cellulose)
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…………………………………………………………………BBC, 03/12/2007
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Cassava
Native to South America
Staple Food of
700 million people
Most important crop
in Africa
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Staple Foods

Food (200 calories) Protein(gm) Carb(gm) Fat(gm)


Whole wheat bread
Brown rice
Corn tortilla
Cassava
Potato (with skin)
Lentils
Pintos
Soybeans

Pork shoulder






(not a staple)
10
4
4
3
6.3
14
13
18
14
40
42
43
47
55
35
35
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Fiber(gm)
3
3
4
0.5
0.3
0
1
11
0
16
6
3
3
0.2
4
12
10
6
?
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Carbohydrate: Best Source of
Energy for the Body

The RDA:
– Minimum amount required to provide adequate
glucose for the brain
– Set at 130 g/day (~ 420 kcalories)

The Range of Healthy Intakes:
– Set at 45% to 65% of energy
***No more than 10% of energy should come
from added refined sugars
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Synthesis of Glucose and Starch
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4-16
Simple Sugar Facts
Simple sugars are small molecules
 Two types: monosaccharides and disaccharides
 Monosaccharides:

– Glucose (“blood sugar”)
– Fructose (“fruit sugar”)
– Galactose

Disaccharides consist of two linked molecules
– Sucrose is a glucose and a fructose
– Maltose is a glucose and a glucose
– Lactose is a glucose and a galactose
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Simple Carbohydrates
Monosaccharides
 Only glucose, fructose, and galactose are
absorbed into bloodstream

10

Disaccharides
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4-13
Synthesis of Sucrose
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Simple Sugar Facts
Disaccharides are broken into
monosaccharides during digestion
 Sucrose is 50% fructose, 50% glucose
 High-fructose corn syrup

– 55% fructose, 40% glucose
– Metabolically not substantially different
than sucrose, but much cheaper to produce
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Glucose
Used for energy
 Fructose and galactose converted to glucose
 The liver and muscles store glucose as the
polysaccharide glycogen
 Glycogen: chains of
linked glucose units

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When body needs energy, glycogen makes
glucose available
 Glucose can also be made from amino acids and
the glycerol of fats
 Cells require glucose as an energy source

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Thiamin, Riboflavin, & Niacin
B-1
B-2
B-3


These water-soluble
"B vitamins" are used
in reactions that
capture and release the
energy in
carbohydrates.
Each of these also has
its own unique
functions in the body.
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Where’s the Sugar?
Simple sugars
are in fruits and
some vegetables
 Except for dairy,
animal products
have no sugars
 Processed sugars

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
Americans consume 84
grams of added sugar per
day, about 17% of the
average caloric intake
– Recommended level is 10% or
less


Sugar consumption up 23%
in past 30 years
Biggest source for many is
soft drinks
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Added Sugars




Sugar is added to food during food processing or
preparation
Nutrition labels list total amount of sugar per serving
Nutrition labels today contain information on total
sugars per serving and do not distinguish between
sugars naturally present in foods and added sugars
Ingredient labels: All simple sugars must be lumped
together under “sweeteners” followed by a parenthetical
list itemizing each type in order of weight
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What’s So Bad about Sugar?





Foods with added sugars
are poor sources of
nutrients
Simple sugars provide only
calories
Many processed foods high
in sugars are also high in fat
Diets often insufficient in
vitamins and minerals when
high sugar intake
Sugar causes tooth decay
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Complex Carbohydrate Facts
Starches, glycogen, and cellulose are
complex carbohydrates - polysaccharides
 Grains, potatoes, dried beans, and corn
contain starch and cellulose, so are
complex carbohydrate sources
 Little glycogen in animal products
 Remember, all carbohydrates have 4
calories per gram

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Complex Carbohydrates

Oligosaccharides

Polysaccharides
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4-14
Carbohydrates: Polysaccharides
Starch, cellulose & glycogen
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Why Whole Grains?
More protein, vitamins and minerals than refined
grains
 More fiber than refined grain foods
 Reduce the risk of heart disease and some types
of cancer




Bran
Endosperm
Germ
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Dietary Fiber Facts




Fiber intake in U.S. below the amount
recommended
People can get recommended amount from wholegrain breads, high-fiber cereal, dried beans and
adequate vegetables and fruits daily
Amounts in food are the same cooked or raw
Fast foods are poor sources of fiber
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Types of Fiber
Classification of edible fibers is based on
chemical characteristics
 Natural foods contain insoluble and soluble
fibers
 Fiber is not digested by human digestive
enzymes
 Fibers are also classified as

– dietary fiber (naturally in the food)
– functional fiber (extracted, then added)
– total fiber
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Types of Fiber

Soluble Fiber
–
–
–
–
Slows glucose absorption
Reduces fat and cholesterol absorption
Combines chemically with water
Natural sources: oats, barley, fruits,
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Insoluble Fiber
Increases stool bulk, softens stool and
shortens transit time through the intestinal
tract
 Sources include

–
–
–
–
–
Whole grain foods
Wheat and corn bran
Seeds and nuts
Potato skins
Zucchini, cauliflower and green beans
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Types of Fiber


Functional fibers (processed fibers)
most are soluble fibers
– reduce post-meal rises in blood glucose levels
– prevent constipation
– may decrease symptoms of irritable bowel
syndrome
– decrease fat and cholesterol absorption

Psyllium, pectin, gels, and seed and plant gums,
are functional fibers
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Fiber: Add it Up





What can you eat in
One day to consume
Recommended fiber?
Men:
38 gm
Women: 25 gm
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Be Cautious
When too much fiber is added too quickly
 High fiber diets can cause diarrhea,
bloating, and gas
 Bacteria in intestines use fiber and excrete
gas
 Adding fiber gradually prevents side effects
 Fluid intake should increase with dietary
fiber

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Type 2 Diabetes
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The Diabetes Epidemic




Diabetes is a growing
epidemic
Related to the global
increase in obesity
Diabetes affects over
400 million worldwide
30 million in U.S.
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Key Concepts and Facts




Diabetes is related to abnormal utilization of
glucose by the body.
The three main forms of diabetes are type 1,
type 2, and gestational diabetes.
Rates of type 2 diabetes increase as obesity
does.
Weight loss and physical activity can prevent
or delay the onset of type 2 diabetes in many
people.
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Sugar Intake and Diabetes
Moderate intake of simple sugars does not
cause diabetes
 Diabetics do not need a "No Sugar" diet

– They need a low sugar diet.

Intake of total carbohydrates must be
controlled –not eliminated
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Diabetes Diagnosis



Type 2 is the most common
A fasting blood sugar level from 100 to 125
mg/dL is considered prediabetes.
If it's 126 mg/dL or higher on two separate
tests, you have diabetes
elevated blood glucose level= high blood sugar
due to inadequate supply or
ineffective utilization of insulin
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Other Diagnosis Methods
Random Plasma Glucose Test: blood
glucose of greater than 200 mg/dl
 The A1C test is a blood test that provides
your average levels of blood glucose over
the past 3 months.

Prediabetes
5.7% to 6.4%
Diabetes
6.5% or higher
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Electron microscopy image
Insulin
A Hormone
 Produced by pancreas
 Reduces blood glucose levels
 Facilitates passage of glucose into
cells
 Low insulin means cells starve
 Cell membranes are sensitive to the
action of insulin

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Type 2 Diabetes
Occurs mainly in overweight
and obese, inactive people
 10% of Americans
 Over 25% in adults over 65
 But becoming more common in
young adults, children and teens
 More significant genetic
component than Type 1

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Acanthosis
Nigricans
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Symptoms of Diabetes
Blurred vision
 Frequent urination
 Weight loss
 Extreme hunger and thirst
 Increased fatigue
 Irritability
 Type 1: Very high blood sugar
► coma ► death

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Effects of high glucose
elevated blood levels of triglycerides
 increased blood pressure
 hardening of the arteries
 Type 2: high insulin production
► can exhaust pancreas
Medications stimulate pancreas to produce
more insulin
Eventually probably will need insulin injections

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Prediabetes and Insulin Resistance
Elevated fasting blood glucose levels
between 110 and 126 mg/dl
characterize prediabetes


Prediabetes increases odds of
developing type 2 diabetes by 10% per
year
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Insulin resistance
 Common
risk
factors for insulin
resistance
– Obesity
– Low levels of
physical activity
– Genetic
predisposition
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Insulin resistance
Insulin lowers blood glucose by binding to
cell membrane receptors
 Receptors activated by insulin, allow
glucose into cells
 Cell membranes ‘resist’ the effects of
insulin
 Lowers the glucose transported into cells
 Leads to elevated blood glucose

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Insulin resistance





When blood glucose levels become high,
pancreas secretes more insulin
Higher insulin keeps glucose levels under
control for years
Pancreas becomes exhausted from over-work
Insulin production slows and glucose
accumulates in blood
When fasting blood glucose levels reach 126
mg/dl or higher, this is Type 2 diabetes
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Metabolic Syndrome
13% of Americans age 20-39 have
metabolic syndrome
 25% of US adult population have metabolic
syndrome
 Diabetes risk increased 25-fold
 Metabolic syndrome precedes diabetes
 Last chance to avoid/postpone diabetes

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Health Consequences of Diabetes

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Heart Disease
Hypertension
Blindness
Kidney failure
Stroke
Loss of limbs due to poor circulation
Men: erectile dysfunction
Women: high risk pregnancies
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The Diabetes Prevention
Program
A Randomized Clinical Trial
to Prevent Type 2 Diabetes
in Persons at High Risk
The DPP Research Group
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Study Interventions
Eligible participants
Randomized
Standard lifestyle recommendations
Intensive
Lifestyle
(n = 1079)
Metformin
(n = 1073)
Placebo
(n = 1082)
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Lifestyle Intervention
An intensive program with the following
specific goals:
• > 7% loss of body weight and maintenance of
weight loss
– Dietary fat goal -- <25% of calories from
–fat
– Calorie intake goal -- 1200-1800 kcal/day
• > 150 minutes per week of physical activity
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Incidence of Diabetes
Percent developing diabetes
Placebo (n=1082)
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Cumulative incidence (%)
All participants
Metformin (n=1073, p<0.001 vs. Placebo)
Lifestyle
(n=1079,
vs.
Metformin
, Plac )
Lifestyle
(n=1079, p<0.001
p<0.001 vs.
Met
, p<0.001 vs.
Metformin (n=1073,
p<0.001vs.
vs. Plac)
p<0.001
Placebo)
Placebo (n=1082)
Risk reduction
3031% by metformin
58% by lifestyle
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10
0
0
1
2
3
4
Years from randomization
The DPP Research Group, NEJM 346:393-403, 2002
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This Study: Preventing
Type 2 Diabetes
•Attain or maintain ideal body weight or
• Lose >7-10% of body weight
• Dietary goals -- <25% of calories
from fat
Stress complex carbohydrates
Calorie intake goal -- 1200-1800 kcal/day
•> 150 minutes per week of physical activity
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About 90% of Type 2 Diabetes
Can be Prevented
If You Smoke, Try to Quit
 Maintain normal weight or lose weight if
needed
 Exercise such as brisk walking 5 hours/week
 Drink water, coffee, or tea (no sugar)

– Avoid sugary drinks, incl. fruit juices and blends
– Equiv. of 12 oz diet soda or 4 packs of splenda ok
– OR 30 packs of splenda (FDA guideline)
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About 90% of Type 2 Diabetes
Can be Prevented, 2
Choose whole grains naturally high in fiber
 Choose good fats instead of bad fats.
 Limit red meat to less than one daily 3-ounce
serving of red meat
 Avoid processed meat like bacon & hotdogs
 Moderate alcohol consumption may decrease
the risk of type 2 diabetes (1 drink a day for
women)
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
How can someone with Type 2 Diabetes
avoid more health problems?



The same diet that prevents Type 2 diabetes will
help keep the diabetic healthier
AND
Carbohydrate-counting diet
– Regular small-to-moderate size meals and snacks
– Oral medications or insulin, as prescribed
Message for people with diabetes:
1) Ask doctor for referral for diabetes classes
2) Don’t fight going on insulin!
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How Do We Choose Meals
Using Carb Choices?
1 serving, or choice =
about 15 grams carbohydrate
Most women need 2 or 3 carb
servings per meal
Most men need 3 or 4 carbs per meal.
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Count the carbohydrates in these meals
Regular
Soda
Tea with
Splenda
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2. Can you count the
carbohydrates in these meals?
Which meal is better? Why?
3-4
carbs
Tea with
Splenda
1 carb per
4 oz.= 3
0
2
1/2
2
2
carb
s
1
1
60
Total: 11 carbs
3-4
carbs
Total 4 carbs
Tea with
Splenda
1 carb per
4 oz.= 3
0
2
1/2
2
2
carb
s
1
1
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Casseroles

How many carb
choices are in one
serving of this
casserole?
•1 cup serving=
•2 carbs
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2.
Casseroles

What can you add to
make this a full meal?
1 carb plus
fat
1/2 c. =1
0
carbs
a side salad
works well
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Diabetes and Heart Disease

Diabetes, prediabetes
and/or metabolic
syndrome increase risk
of heart disease

Diabetics need to
follow a heart-healthy
diet and lifestyle.
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Curing Diabetes
Type 2 Diabetes:
Change our obesigenic environment
Make it easier to get nutritious foods
than junk foods
Build physical activity into our lifestyle
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Diabetes in the Future
Worldwide rise in type 2 diabetes is
predicted but not inevitable
 Could be lowered by environmental and
lifestyle changes to reduce overweight
and increase physical activity
 Education on connection between
diabetes and body weight may help
 Hoped-for future of diabetes is to negate
dire forecasts of the experts

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Carbs at the Beacon
67
p. 9
HOW many carbs??
How much fat? Good fat or bad fat?
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Burger Only:
Calories 438
Carbs 38 gram
Fat 20 grams
TOTAL
Calories 1208
(Notice, we still
 Carbs 132 grams (9 servings)
don't have a
beverage!)
 Fat 59 grams (mostly bad)

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