Lecture Presentation Outline

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Lecture Presentation Outline
I.
The Diabetes Epidemic
 Instructor Resources: Unit 13 Nutrition Scoreboard transparency master; Unit 13 PowerPoint
presentation on Multimedia Manager
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Diabetes is an epidemic
Related to the global increase in obesity
Diabetes affects 200 million worldwide
17 million in U.S.
II. Types of Diabetes
 Instructor Resources: transparency #39: Type 1 and Type 2 Diabetes
A. Three forms of diabetes: type 1, type 2, and gestational diabetes
1. Type 1
a. Insulin deficiency
b. Accounts for 10% of cases
c. Risk factors: viral infection early in life (or other triggers in genetically sensitive
individuals) that destroys part of the pancreas; young birth; age; certain medications
d. Treatment: insulin, diet, exercise
2. Type 2
a. Insulin deficiency possible in advanced stages of the disease
b. Accounts for 90% of cases
c. Risk factors: obesity (especially abdominal fatness); sedentary lifestyle; insulin resistance;
low weight for certain ethnicities; family history; older age
d. Treatment: weight loss (in most cases), increased physical activity, sometimes oral
medications and/or insulin
B. Type 2 is the most common
C. Both types are diagnosed when fasting levels of blood glucose are 126 mg/dl and higher and
generally take years to develop
D. In all cases, the central defect is elevated blood glucose level caused by an inadequate supply or
ineffective utilization of insulin
E. Characteristics of Insulin
1. Insulin is a hormone produced by pancreas
2. Reduces blood glucose levels
3. Facilitates passage of glucose into cells
a. Low insulin means cells starve
4. Cell membranes are sensitive to the action of insulin
a. Cells starve if membranes lose sensitivity
III.
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Effects of high glucose
Elevated blood levels of triglycerides
Increased blood pressure
Hardening of the arteries
A. Poorly controlled, untreated diabetes produces:
1. Blurred vision
2. Frequent urination
3. Weight loss
4. Increased susceptibility to infection
5. Delayed wound healing
6. Extreme hunger and thirst
B. Diabetes may contribute to:
1. Heart disease
2. Hypertension
3. Blindness
4. Kidney failure
5. Stroke
6. Loss of limbs due to poor circulation
IV. Type 2 Diabetes
A. Characteristics
1. Occurs in overweight and obese, inactive people
2. Mostly in people over 40
3. Increasingly common in children and adolescents
4. Genetic component
B. Prediabetes
1. Elevated fasting blood glucose levels below the cut-point used to diagnose type 2 diabetes
characterize prediabetes
2. 6% of U.S. adults, and 314 million people worldwide, are at risk of type 2 diabetes due to
prediabetes
3. Prediabetes increases odds of developing type 2 diabetes by 10% per year
C. Insulin resistance
1. Common risk factors for insulin resistance
a. Obesity
b. Low levels of physical activity
c. Genetic predisposition common risk factor for insulin resistance
2. Insulin lowers blood glucose by binding to cell membrane receptors
3. Receptors activated by insulin, allow glucose into cells
4. Cell membranes ‘resist’ the effects of insulin
a. Lowers the glucose transported into cells
b. Leads to elevated blood glucose
5. When blood glucose levels become high, pancreas secretes more insulin
a. Higher insulin keeps glucose levels under control for years
b. Pancreas becomes exhausted from over-work
6. Insulin production slows or stops and glucose accumulates in blood
7. When fasting blood glucose levels reach 126 mg/dl or higher, type 2 diabetes is underway
D. Metabolic Syndrome
1. Obese hypertensive people and type 2 diabetes = high risk of heart disease
2. Insulin resistance leads to cluster of symptoms
a. High central body fat
b. High blood insulin
c. High blood pressure
d. Elevated blood triglycerides
e. Low levels of HDL cholesterol
f. High blood glucose
3. Diagnosis made when three abnormalities identified
a. If 4 or 5 abnormalities heart disease risk goes up 4-fold
b. Diabetes risk increased 25-fold
4. 25% of men and women in U.S. have metabolic syndrome
E. Managing Type 2 Diabetes with Diet and Exercise
1. Weight loss alone significantly improves blood glucose control
2. Proper diets are crucial
a. Complex carbohydrates including whole grain breads and cereals, and other high fiber
foods, vegetables, fruits, low-fat milk and meats, and fish
b. Unsaturated fats
c. Regular meals and snacks
d. Chromium supplements (sometimes helpful)
3. Dietary management
a. For heart disease risk reduction
b. Blood glucose control
c. Monounsaturated fats, such as vegetable oils, nuts, seeds, and lean meats, and sea foods
are recommended
4. Oral medications decrease insulin resistance and blood lipids
5. Insulin, if needed
F. Glycemic Index and Glycemic Load
 Instructor Resources: Activity 13-1: Recipes for Diabetes Management
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Foods that increase blood glucose require more insulin to move glucose into cells
Carbohydrate-containing foods that affect blood glucose given glycemic index value
Low glycemic index foods decrease triglyceride levels and insulin need in adults with insulin
resistant type 2 diabetes
Glycemic Index
a. Elevation in blood glucose caused by food that provides 50 grams of carbohydrate,
compared to rise in blood glucose level from consuming 50 grams glucose (another
standard is white bread).
b. Adjusting food choices toward low glycemic index foods is helpful for people to prevent
or control type 2 diabetes, or diminish the effects of insulin resistance.
c. Glycemic index is based on 50 grams of carbohydrate
d. Foods with low carbohydrate: glycemic index applies only to large amount
1. You would have to eat 7 raw carrots to ingest 50 grams of carbohydrate.
Glycemic Load
a. A new Index - The blood glucose-raising potential of a specific amount of food
b. Glycemic load calculated by multiplying grams of carbohydrate in an amount of food
times the food’s glycemic index, then dividing by 100
c. A raw carrot has 7 grams of carbohydrate and a glycemic index of 47. Its glycemic load
would be calculated as:
1. 7 X 47 = 329
2. 329/100 = 3.29
3. Glycemic load = 3.29
6. Glycemic Index is called GI
a. Blood glucose-raising effect of a raw carrot isn’t much
b. 4 slices (4 oz) of French bread glycemic load is 49.4
c. That level raises blood glucose and insulin levels far more than a carrot
7. Low GI Foods
a. Low GI foods for dietary management of type 2 and gestational diabetes not a primary
recommendation in the U.S.!
b. Consumption of low GI foods is useful part of management of insulin resistance and
metabolic syndrome, but secondary aid to blood glucose control among diabetics
G. Sugar Intake and Diabetes
1. High intakes of simple sugars does not cause diabetes
2. Sugar does not have to be eliminated from diet of people with diabetes
3. Intake of total carbohydrates is most strongly related to blood glucose levels
4. High-sugar diets increase blood triglycerides levels
H. Prevention of Type 2 Diabetes
 Instructor Resources: Activity 13-2: Assessing Diabetes Risk
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Weight loss and exercise
a. Prediabetics reduced risk of type 2 diabetes over 50%
b. Lost body weight of 7%
c. Only 150 minutes a week of exercise
Diets rich in whole grain and high fiber foods are protective against the development of type
2 diabetes and appear to aid weight loss
Type 1 Diabetes
Type 1 diabetes results from a deficiency of insulin
Accounts for about 10% of all cases
Diagnosis of type 1 peaks around the ages of 11 to 12 years and usually occurs before age 40
A. Type 1 diabetics measure blood glucose levels several times daily
1. Adjust insulin dose according to the results
2. Insulin pumps release insulin in response to blood glucose level
3. Pumps improve blood glucose control
B. Even small weight loss benefits blood glucose control in overweight and obese individuals with
type 1 diabetes
C. Insulin deficiency from viral infection or allergic reaction
1. Destroys the portion of pancreas that produces insulin
2. Medications for high blood pressure, arthritis, etc. may contribute to type 1 diabetes
3. Breastfeeding for first four months may confer protection against type 1 diabetes
4. Environmental factors more important than genetic background in Type 1 diabetes
a. Incidence of Type 1 varies 36-fold among countries, suggesting environmental factors
play a key role in development
VI. Gestational Diabetes
 3 to 6% of women develop gestational diabetes
A. Incidence varies by age, body weight, and ethnicity
1. Native and African Americans, obese women, women over 35 years, and women with low
physical activity have greater risk
2. Infants of women with diabetes fat at birth, have blood glucose control problems after
delivery
a. At greater risk for diabetes later in life
b. 6 to 20% will have a physical abnormality that may threaten survival or a high quality of
life
B. Women with gestational diabetes are insulin resistant
1. Control blood glucose levels with an individualized diet and exercise plan
2. Some women require daily insulin injections for blood glucose control
C. Gestational diabetes disappears after delivery
1. But non-insulin-dependent diabetes may appear later in life
2. Exercise, maintenance of normal weight, and consumption of a healthy diet reduce the risk
that diabetes will return
VII. Hypoglycemia
 Instructor Resources: CNN Today Nutrition Vol. 2: Feed Your Mind (1:02)
A. Characteristics
1. Due to abnormally low blood glucose levels
2. Rare disorder, not often diagnosed
a. Diagnosis is difficult
b. Blood tests for glucose must be conducted when the symptoms are present
3. Incidence % of hypoglycemia not known
B. Caused by excessive insulin in the blood
C. Oversupply caused by:
1. Tumors that secrete insulin
2. Other health problems
3. High alcohol intake on an empty stomach
4. In diabetes by insulin dose too high
5. Hypoglycemia occurs during prolonged starvation, but blood glucose levels become very
low only when starvation threatens life
D. Symptoms include:
1. Weakness
2. Sweating
3. Nervousness
4. Confusion
5. Irritability
6. Symptoms appear before levels are clinically abnormal, responses vary to low-normal
glucose level
7. Symptoms disappear 5 - 15 minutes after candy, orange juice or similar food is consumed
8. Increased glucose levels must be maintained after drop in glucose level is corrected
E. High sugar intakes do not cause hypoglycemia
F. People who have this disorder should consult a physician and have blood glucose level checked
when the symptoms normally occur
G. Standard diet therapy for hypoglycemia is five to six small meals from a variety of complex
carbohydrate and high-protein foods
1. Avoid alcohol and snacks high in simple sugars
VIII. Diabetes in the Future
A. Rise in type 2 diabetes not inevitable
1. Could be lowered by environmental and lifestyle changes to reduce risk for, and incidence of,
overweight and obesity
2. Education on connection between diabetes and body weight may help
B. Hoped-for future of diabetes is to negate dire forecasts of the experts
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