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Chapter 18 – Diet and Health
Learning Objectives
After completing Chapter 18, the student will be able to:
1. Describe the immune system and the cells that compose it.
2. Identify nutrients that are known to enhance immunity.
3. Discuss the role of nutrition and lifestyle in the development of chronic disease.
4. Describe cardiovascular diseases and risk factors in the development of each.
Assignments and Other Instructional Materials
The following ready-to-use assignments are available in this chapter of the instructor’s manual:
• New! Case study
• Worksheet 18-1: Therapeutic Diets1
Other instructional materials in this chapter of the instructor’s manual include:
• Answer key for How To (pp. 616, 617) activities
• Classroom activities
• Worksheet answer keys (as appropriate)
Lecture Presentation Outline4
“Of special interest to…” symbol key: = Hot Topic = Personal Health
= Health Care Professionals = Science Majors
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Key to instructor resource annotations (shown to the right of or below outline topics):
PL = Available on Power Lecture DVD-ROM (ISBN 0538797592): V = video
Introductory/whole chapter resources: PL figure JPEGs; Test Bank; WS 18-1, 18-2, CA 18-1, 18-2
I. Nutrition and Infectious Diseases
Personal strategies to prevent infectious disease are important. Nutrition intervention can help prevent
malnutrition and minimize the wasting that accompanies AIDS.
A. The Immune System Website HN 18-1
1. Organs of the immune system fight antigens
2. Phagocytes
a. Engulf and digest invaders; a process is called phagocytosis.
b. Secrete special proteins called cytokines that activate a metabolic and immune response.
3. Lymphocytes: B-cells
4. Lymphocytes: T-cells
a. Release powerful chemicals to destroy foreign particles.
d. Participate in the rejection of transplanted tissue.
B. Nutrition and Immunity 10e TRA 164; Website HN 18-2
1. Malnutrition compromises immunity.
C. HIV and AIDS Website HN 18–3, 18-4
1. HIV (human immunodeficiency virus) is the infection that attacks the immune system and disables
the body’s defenses.
D. Inflammation and Chronic Disease
1. Inflammation occurs in response to infection or injury.
II. Nutrition and Chronic Diseases 12e TRA 24, 25; 10e TRA 166; IM CI 18.1
Four of the top ten causes of death are related to diet. There are also genetic and lifestyle risk factors that are
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III. Cardiovascular Disease (CVD)
Atherosclerotic plaques can raise blood pressure, cause abnormal blood clotting, and cause heart attacks and
A. How Atherosclerosis Develops 10e TRA 168
1. Atheromatous plaque builds on artery walls and leads to inflammation.
2. Inflammation
a. Cells lining the blood vessels incur damage.
b. Inflammatory response using macrophages that become the cells of plaque.
3. Plaques – Fibrous coating can be torn away with a surge in blood pressure.
4. Blood Clots
a. Platelets cover the damaged area and form a clot.
b. Thrombosis is a blood clot that sticks to an artery and grows large enough to restrict or close off a
5. Blood Pressure and Atherosclerosis
a. Arteries are narrowed due to plaque, clots, or both.
b. The heart must generate more pressure to deliver blood to the tissues.
c. Higher blood pressure results in further damages.
6. The Result: Heart Attacks and Strokes
a. Angina – pain or pressure feeling around the area of the heart.
B. Risk Factors for Coronary Heart Disease IM WS 18–3, CA 18–3, CI 18.3
1. Diet and physical activity are modifiable risk factors.
2. Age, Gender, and Family History
a. Cannot change these factors.
3. High LDL and Low HDL Cholesterol
a. LDL
1. Excess LDL (low-density lipoproteins) become available for oxidation, high risk.
2. Risk factors for LDL cholesterol
a. Desirable: 100 mg/dL.
b. HDL
1. HDL (high-density lipoproteins) represent cholesterol being carried back to the liver,
reduced risk.
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c. High: 40 mg/dL.
c. Total cholesterol
4. High Blood Pressure (Hypertension)
a. Injures artery walls and accelerates plaque formation, which in turn increases blood pressure.
b. Blood pressure (systolic and/or diastolic pressure)
1. Desirable: 120/80.
5. Diabetes
a. Risk similar to people with established CHD.
b. CHD risk equivalents.
6. Obesity and Physical Inactivity
a. Obesity, especially abdominal obesity, and physical inactivity increase risk.
b. Body mass index
1. Desirable: 18.5-24.9.
7. Cigarette Smoking
a. Powerful factor for increased risk.
b. Increases blood pressure and the workload of the heart.
8. Atherogenic Diet
a. A diet high in saturated fats, trans fats, and cholesterol and low in fruits and vegetables elevates
9. Other Risk Factors
a. Emerging risk factors and predictions.
b. Elevated triglycerides are a marker for other risk factors and being studied in relation to CHD.
1. Desirable levels of fasting triglycerides: 150 mg/dL.
c. Diabetes and overweight.
10. Metabolic Syndrome – also called Syndrome X or insulin resistance syndrome.
a. Insulin resistance is a risk factor.
b. Any three of the following factors
1. Abdominal obesity
a. Men: Waist circumference 40 inches.
C. Recommendations for Reducing Coronary Heart Disease Risk
1. Cholesterol Screening – at least two times at least one week apart.
2. Lifestyle Changes PL V “Heart–Healthy Habits for Women,” “Cholesterol-Lowering Diet”
a. Balance energy intake with energy needs.
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d. Limit foods with a high content of cholesterol ( 300 mg/day).
e. Choose foods high in soluble fiber: vegetables, fruits, and whole grains.
f. Choose high-potassium, low-sodium foods.
g. Limit sodium to 2,300 mg/day.
IV. Hypertension
Hypertension with accompanying atherosclerosis can cause heart attacks and strokes. Weight control is the most
effective dietary strategy for treating hypertension.
A. How Hypertension Develops 11e TRA 29
1. Blood flow to the kidneys is reduced so the kidneys expand blood volume and constrict peripheral
B. Risk Factors for Hypertension
1. Age – risk increases with age.
C. Treatment of Hypertension IM CI 18.4
1. Weight control is the one of the most effective treatments.
2. Physical activity will help – moderate aerobic for 30-60 minutes most days.
3. The DASH Diet – Dietary Approaches to Stop Hypertension Website HN 12–1, IM CA 18-4
a. Grains: 6-8 ounces.
4. Salt/Sodium Intake
5. Drug Therapy
a. Diuretics and antihypertensive agents.
b. Watch potassium.
V. Diabetes Mellitus 11e TRA 30
Diabetes is characterized by high blood glucose (hyperglycemia) and either insufficient insulin, ineffective
insulin, or both. Diabetes treatment involves the coordination of diet and/or drugs and physical activity to
control blood glucose fluctuations and control or lose weight.
A. How Diabetes Develops PL V “Diabetes Prevention”; 11e TRA 31
1. Impaired glucose tolerance or prediabetes.
2. Type 1 Diabetes
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3. Type 2 Diabetes
a. 90-95% prevalence in diabetic population.
b. Occurring in children and adults.
B. Complications of Diabetes 11e TRA 32
1. Diseases of the Large Blood Vessels
a. Atherosclerosis tends to develop early and is more severe.
b. Long-term, intensive intervention targeting multiple factors can reduce risk.
C. Recommendations for Diabetes IM CI 18.5
1. Total Carbohydrate Intake
a. Consistent intake helps to regulate blood sugar.
b. Too little carbohydrate consumption can lead to hypoglycemia.
2. Carbohydrate Sources
3. Dietary Fat
4. Protein
5. Alcohol
6. Recommendations for Type 1 Diabetes
a. Adjust insulin doses.
b. Optimal nutrition status.
1. Control blood glucose with consistent carbohydrate intake at meals and snacks.
2. Achieve desirable blood lipids.
VI. Cancer
Cancer is the growth of malignant tissue. Dietary factors that initiate cancer development include alcohol and
heavily smoked foods. Dietary factors that promote cancer once it has started include saturated fat and trans fat.
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Dietary factors that serve as antipromoters—that is, protect against the development of cancer—include fiber,
antioxidant nutrients, and phytochemicals. Eating a variety of healthful foods and adapting a physically active
lifestyle is the best advice to lower cancer risk.
A. How Cancer Develops 10e TRA 172
1. Carcinogenesis is the development of cancer from mutated cells and can result in the formation of an
abnormal mass, or tumor.
2. Classifications of cancers
a. Adenomas – glandular tissues.
3. Tumors can metastasize, or spread to other areas of the body.
4. Carcinogens are substances an individual is exposed to that can lead to cancer.
5. Environmental Factors
6. Dietary Factors—Cancer Initiators
a. Additives and pesticides.
b. Minimize carcinogens when cooking – use foil on grill, do not burn foods, and marinate meat
beforehand.
7. Dietary Factors—Cancer Promoters
a. High-fat diets correlate with high cancer rates in animals.
b. Omega-3 fatty acids may be protective.
8. Dietary Factors—Antipromoters
a. Fruits and vegetables and low incidence of cancer.
B. Recommendations for reducing cancer risk PL V “Nutrition and Cancer”; IM CI 18.2
1. Maintain a healthy body weight.
2. Be physically active.
3. Limit consumption of energy-dense foods.
VII. Recommendations for Chronic Diseases 11e TRA 33; 12e TRA 26; IM CA 18-5
A. Recommendations for the Population – making dietary changes to forestall or prevent disease is the
preventive or population approach.
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VIII. Highlight: Complementary and Alternative Medicine IM CA 18–6, CI Highlight
Alternative therapies come in many different practices and products. Benefits and risks may be great, small, or
nonexistent. Wise consumers and health care professionals accept the beneficial effects that have been
confirmed by research to be safe and effective. They reject those practices that cause harm. Making healthful
choices requires understanding and seeking out reliable sources of information.
A. Defining Complementary and Alternative Medicine
1. Complementary and alternative medicine: diverse medical and health care systems, practices, and
products that are not currently considered part of conventional medicine.
a. Acupuncture – uses long, thin needles to relieve pain or illness.
b. Aroma therapy – uses plant or flower oil extracts to enhance health.
c. Ayurveda – uses herbs, diet, meditation, message, and yoga to prevent and treat disease.
d. Bioelectromagnetic medical applications – uses electrical or magnetic energy to increase
healing.
2. Conventional medicine: diagnosis and treatment of diseases as practiced by medical doctors, doctors
of osteopathy, and allied health professionals.
3. Integrative medicine is an approach that combines conventional and complementary therapies.
B. Sound Research, Loud Controversy
1. Little research – folklore, tradition, and testimonials.
2. Placebo effect can bring about a healing effect in people who believe they are receiving treatment.
3. Risks versus Benefits 10e TRA 174
C. Nutrition-Related Alternative Therapies
1. Foods
a. Potential health benefits of soy in relation to heart disease are documented.
b. More research is needed on phytoestrogens of soy to manage symptoms of menopause.
2. Vitamin and Mineral Supplements
d. Herbal preparations can vary from batch to batch.
4. Herbal Precautions
a. “Natural” does not mean beneficial or safe.
b. Herbs are not drugs; they are dietary supplements.
c. Lack of information and discrepancies.
1. True identification of herbs.
2. Purity of herbal preparations.
D. Internet Precautions
1. Advertising and marketing of their own products.
2. Quotations from researchers and physicians may be taken out of context.
3. Increased access to products.
E. The Consumer’s Perspective
1. Seek alternative medicine because it is more in line with their beliefs about health and life.
Case Study5
Ellen is a 53-year-old married woman with multiple medical problems, including chronic back pain. She takes
medication for high blood pressure and hypercholesterolemia, both of which are currently under control. She also
takes pain medications every day and has difficulty walking, although she occasionally attends a water exercise class
at the local sports center. She is 5 feet 6 inches tall and weighs 236 pounds. She states she has been overweight most
of her life and confesses that food, especially sweet foods, are a comfort to her when she has physical or emotional
pain. Her diet history reveals an intake of 2 or 3 cans of ginger ale or root beer each day. Her usual meals with her
husband include meat or chicken (she does not like fish) and vegetables such as corn or potatoes. She snacks on
several types of frozen desserts between meals. She enjoys milk on occasion but admits it is not a part of her regular
diet. A recent visit to her doctor reveals a weight gain of 15 pounds over the past 6 months and an increase in her
fasting blood glucose level into the “pre–diabetes” range. She has no family history of diabetes. Her doctor has
recommended she lose weight and make lifestyle changes to prevent her from developing diabetes.
1. Using the information in Table 18–3, list the risk factors that are evident from Ellen’s history and the chronic
diseases that impact her life.
2. What advice would you give Ellen regarding her intake of sweetened beverages as it relates to her obesity and
blood glucose levels?
3. Using strategies suggested in Table 18–6 and the “How To” on page 617, suggest 2 or 3 dietary changes that
would help Ellen reduce her risk for heart disease.
4. What dietary plan would help Ellen control her blood pressure as well as her blood cholesterol levels? What are
the main features of this diet?
5. Prepare a sample one-day menu with 3 meals and 1 or 2 snacks for Ellen that includes the minimum servings of
each food group for the DASH Eating Plan as outlined in Table 18-8.
6. According to Table 18-12, what are the four dietary guidelines that are recommended to decrease the risks
associated with all the major chronic diseases?
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Answer Key:
1. Diet high in added sugars: obesity. Diet low in fruits, vegetables, and other foods rich in fiber and
phytochemicals: diabetes, atherosclerosis, obesity. Diet low in vitamins and minerals: hypertension,
Suggested Classroom Activities
Some instructors present information from this chapter throughout the course; others prefer to cover this chapter
separately. If you would like to spread this information throughout the course, you may want to present information
about heart disease when discussing Chapter 5 and information about AIDS and immunity when discussing Chapter
6.
Classroom Activity 18-1: Chapter Opening Quiz
Objective: Introduction to chapter Class size: Any
Instructions: As a way of introducing any new chapter, give a quiz to the class. This is a quiz designed to be
projected overhead. For details, please see Chapter 1, Classroom Activity 1–7.
Classroom Activity 18-3: Student Health Profile
Key concept: Preventive health measures Class size: Any
Instructions: Instruct students to schedule a physical to screen for potential health problems. These are some possible
measures that can be obtained: height, weight, body mass index, percent body fat, age, resting heart rate, target heart
rate, maximal heart rate, resting systolic blood pressure, resting diastolic blood pressure, total cholesterol, HDL, and
LDL.
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Classroom Activity 18-5: Exploring Victim-Blaming Attitudes
Key concept: Attitudes about lifestyle-related illnesses Class size: Any
Instructions: Instruct students to record on a sheet of paper their first thoughts when a situation is described. Have
them note, on a scale of 1 to 10, their feelings of compassion for the person in each scenario.
Have students share their attitudes toward each of these situations and their feelings of compassion. Ask how many
reported that their feelings of compassion were low for those who engaged in behaviors that increased their risks for
the diseases. Discuss the negative effects of victim blaming and the positive effects of encouraging responsibility
without casting blame and shame.
Classroom Activity 18-6: Exploring CAM6
Key concept: Complementary and alternative medicine Class size: Small to medium
Instructions: There is perhaps no area more controversial than the area of alternative therapies, including the use of
herbs, supplements, mind-body therapies, and even alternative dietary approaches to treating disease and aliments
Hint: One of the best resources in the area of herbal therapies is Mark Blumenthal. The students will be well guided
by this writings, books, and work in this area and he is a popular speaker for the American Dietetic Association and
the Dietetic Practice Group focused in this area.
One other exercise that can be fun on this topic is to ask students to either write a paper or debate in class the pros
and cons of alternative therapies, including nutrition as an alternative therapy. As we have moved throughout this
text, I have tried to express the perspective that the RD must remain flexible to a client’s perspective or choice of
taking supplements, etc. Some dietitians are of the mind that when an individual does consume a well-balanced diet,
supplementation or herbals are not necessary. While this may be true, it is important to maintain the perspective of
the consumer. Students studying the field of nutrition come with many very strong opinions, including strong
opinions about alternative therapies with supplements and herbals. Allowing students to voice their opinions and
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allowing them to hear both sides of the argument is a valuable lesson while they are still in school and can benefit
from hearing the potential future arguments that their clients will soon voice to them as practitioners.
How To “Try It!” Activities Answer Key
How to Assess Your Risk of Heart Disease
Students have the choice of adding up a heart disease risk score using the How To itself or using the online risk
assessment tool at the American Heart Association website. Answers will be individualized.
How to Implement a Heart-Healthy Diet
Students should submit a reasonable 1-day meal plan and a nutrient analysis of the chosen foods, along with an
Critical Thinking Questions7
These questions will also be posted to the book’s website so that students can complete them online and e–mail their
answers to you.
1. Discuss how altered nutrition status can affect the immune system.
Answer: The immune system is a critical system within our body, protecting the body from daily exposure to
harmful bacteria, viruses, toxins, and fungal invasions. In addition, the immune system constantly surveys the
body in search of foreign cells and rids the body of any invaders through its system of phagocytosis.