xx
Cardiovascular disease (CVD) is the major killer of North Americans. Each year, about
500,000 people die of CVD in the United States, about 60% more than die of cancer.
The fi gure rises to almost 1 million if strokes and other circulatory diseases are included.
About 1.5 million people in the United States each year have a heart attack. The overall
male-to-female ratio for heart disease is about 2:1. Women generally lag about 10 years
behind men in developing the disease. Still, it eventually kills more women than any other
disease—twice as many as cancer. And, for each person in North America who dies of CVD,
20 more (over 13 million people) have symptoms of the disease.
High-fat diets, especially those rich in saturated and trans fats, increase the risk
of CVD. (Recall that the vascular system includes the blood, heart, arteries, and veins.)
The symptoms develop over many years and often do not become obvious until old age.
Nonetheless, autopsies of those under 20 years of age have shown that many already had
atherosclerotic plaque in their arteries.
Development of CVD
Atherosclerotic plaque is probably fi rst deposited to repair injuries in the lining in any
artery. The damage that starts plaque formation can be caused by smoking, diabetes,
hypertension, homocysteine (likely, but not a major factor), and LDL.
14-16
Viral and bacterial
infections and ongoing blood vessel infl ammation also may promote plaque formation.
17
As atherosclerosis progresses, plaque thickens over time, causing arteries to harden,
narrow, and become less elastic. This makes them unable to expand to accommodate
the normal ups and downs of blood pressure. Affected arteries are further damaged as
blood pumps through them and pressure increases. In the fi nal phase, a clot or spasm in
a plaque-clogged artery blocks the fl ow of blood and leads to a heart attack (myocardial
infarction) or stroke (cerebrovascular accident).
R ecall that blood supplies the heart muscle and brain—and other body organs—with
oxygen and nutrients. When blood fl ow via the coronary arteries surrounding the heart
is interrupted, a heart attack may occur , which damages the heart muscle. If blood fl ow
to parts of the brain is interrupted long enough, part of the brain dies, causing a stroke.
Factors that typically bring on a heart attack in a person at risk include dehydration, severe
emotional stress, strenuous physical activity when not otherwise physically fi t, sudden
awakening during the night or just getting up in the morning (linked to an abrupt increase
in blood pressure and stress), and high-fat meals, which increase blood clotting.
Risk Factors for CVD
In addition to a high-fat diet, the American Heart Association has identifi ed several other
factors that affect the risk of heart disease. The more risk factors a person has, the greater
the risk of CVD. Some of the risk factors cannot be changed, but others can. The risk factors
that cannot be changed are age, gender, genetics, and race.
• Age. The risk of CVD increases with age. Over 83% of people who die of CVD are at least
65 years old.
• Gender. Men have a greater chance of having a heart attack than women do, and they
have attacks earlier in life. Even after menopause, when women’ s death rate from heart
disease increases,
18
it’ s not as great as the risk men face.
• Genetics. Having a close relative who died prematurely from CVD, especially before age
50, may increase the risk. Those with the highest risk of premature CVD have genetic
Cardiovascular Disease (CVD)
Medical Perspecti ve
A Healthy People 2010 goal is to reduce
death from coronary heart disease by 30%,
compared with today’s incidence.
CVD typically involves the coronary
arteries and thus is frequently termed
coronary heart disease (CHD) or coronary
artery disease (CAD).
homocysteine Amino acid not used in
protein synthesis but, instead, produced
during metabolism of the amino acid
methionine. Homocysteine is likely toxic
to many cells, such as those lining the
blood vessels.
preface
Improved Personal Focus and Applications
Applying Nutrition on a Personal Level
A key objective in nearly all introductory courses is for students
to be able to apply their new knowledge of nutrition to their own
lives. Practical applications clearly linked to nutritional science con-
cepts are woven throughout each chapter to help students apply
their knowledge to improving and maintaining their own health
and that of others for whom they are responsible, such as future
patients or offspring. Examples of features that help students draw
relationships from nutrition concepts to their own lives include
• Updated case studies showcase realistic scenarios and thought-
provoking questions.
• Two Take Action features in each chapter (many are new) al-
low students to examine their own diets and health issues.
• New Medical Perspective features highlight the role of nutri-
tion in the prevention and treatment of diseases. These topics
will be especially interesting to students planning careers in di-
etetics or health-related fields.
Stimulating Pedagogy
The pedagogical elements that support student learning and ap-
plication were retained, updated, or enhanced to make nutritional
science even more readable, accessible, and achievable for today’s
students. The following elements are just some of the tutorial aids
designed to challenge students to organize their thinking, focus
their studying, synthesize information, think critically, and apply
concepts to everyday situations.
• The former Expert Opinion feature, now called Expert Perspec-
tive from the Field, emphasizes cutting-edge topics and dem-
onstrates how emerging, and sometimes controversial, research
results affect nutrition knowledge and practice.
After graduating from college, Pierre, a 24-year-old accountant, noticed he had gained 8 pounds in the past year. His employer
provides free soft drinks, juice, and bottled water . Pierre decides to keep track of his food intake for a couple of days to track his
calories. Just his beverage intake is provided here. To estimate his energy intake from beverages, use Table 14-2 and a nutrient
database, nutrient analysis computer program, or visit this website: www.nal.usda.gov/fnic/foodcomp/search . Do you think
he obtains too many calories from these beverages? What are better alternatives?
CASE STUDY
Breakfast
12 oz mocha with whipped cream
6 oz orange juice
Morning Break
12 oz cranberry juice
10 oz water
Lunch
12 oz regular cola
Afternoon Break
12 oz regular root beer or apple juice
After Work
1 or 2 12-oz beers
10 oz fat-free milk
Is Your Diet High in Saturated and Trans Fat?
Take ActionT
Instructions: In each row of the following list, circle your typical food selection from column A or B.
Column A Column B
Bacon and eggs or Ready-to-eat whole-grain breakfast cereal
Doughnut or sweet roll or Whole-wheat roll, bagel, or bread
Breakfast sausage or Fruit
Whole milk or Reduced-fat, low-fat, or fat-free milk
Cheeseburger or Turkey sandwich, no cheese
French fries or Plain baked potato with salsa
Ground chuck or Ground round
Soup with cream base or Soup with broth base
Macaroni and cheese or Macaroni with marinara sauce
Cream/fruit pie or Graham crackers
Cream-fi lled cookies or Granola bar
Ice cream or Frozen yogurt, sherbet, or reduced-fat ice cream
Butter or stick margarine or Vegetable oils or soft margarine in a tub
Interpretation
The foods listed in column A tend to be high in saturated fat, trans fatty acids, cholesterol, and total fat. Those in column B generally are low in these
dietary components. If you want to help reduce your risk of cardiovascular disease, choose more foods from column B and fewer from column A.
Nutrition, agriculture, access to food and water, food
processing and preparation, public policy, personal health,
and environmental quality are all interrelated. When these
relationships are out of balance and practices are not
sustainable, the quality, quantity, and future of our food and
water supplies may be negatively affected. Concern about
these interrelationships, as well as environmental quality
and personal health, may affect food choices. For example,
consumers are increasingly choosing organic foods because of
personal and environmental health concerns.
According to Angie Tagtow,* a registered dietitian and
sustainable food systems advocate, the most important reason
for eating organic fruits and vegetables is to decrease exposure
to pesticide residues. By consuming organic meat, dairy , and
eggs, she notes, consumers avoid the antibiotics and synthetic
hormones commonly used in conventional farming. Another
benefi t is that animals that are certifi ed organic often are
treated humanely and have access to pasture. Tagtow’s own
concerns about health and the environment have led her to
seek locally grown organic food. The benefi ts of local food
systems, where local farmers and producers grow and sell
foods to local consumers, may include increased biodiversity
of farm products, increased access to fresh food, decreased
impact on the environment, and greater community
economic development.
75
Tagtow states that her vision of an ideal food system is
one that provides food that is
• Healthy—food that has optimal nutritional value, is free
of preser vatives and additives, and does not promote the
development of diet-related chronic diseases
• Green—food production that has no or low environmental
impact, keeps ecosystems in balance, uses minimal
nonrenewable energy (e.g., oil and coal), and recycles
wastes
• Fair—food production that does not exploit anyone or
anything, enables farmers to earn enough income to be
economically self-suffi cient, keeps local food systems
economically sound, and contributes to the overall
economic development of communities
• Affordable and accessible—food that is safe,
nutritious, produced in a sustainable manner, and
equally and regularly available to ever yone
When asked for advice on how those with a limited
budget can incorporate organically grown foods in their
diets, Tagtow recommended identifying local organic
farmers and buying fruits, vegetables, dairy , eggs, or meat
directly from them. Visiting farmers’ markets, food co-
ops, Community Supported Agriculture (CSA) farms, or
Cooperative Extension System websites can help consumers
learn which foods are produced locally. Many CSA farms rely
on volunteers during the growing season—this may provide
those with limited budgets an opportunity to access high-
quality, fresh food. T o save money, she also recommends
buying fresh food when it is in season.
Consumers who fi nd it too costly to buy all organic
foods may want to focus on specifi c foods. For instance,
Tagtow pointed out that the foods with the highest pesticide
residues are apples, peaches, bell peppers, celery , nectarines,
strawberries, cherries, lettuce, imported grapes, and pears—
consumers concerned about pesticide residues may want to
choose organic versions of these foods whenever they can.
T o learn more about local food systems and organic foods,
visit the Leopold Center at www.leopold.iastate.edu/index.
htm; The Organic Center at www.organic-center.org/; Local
Har vest at www.localhar vest.org/; and the Organic Farming
Research Foundation at ofrf.org/index.html.
*Angie Tagtow, MS, RD, LD, is a 2008–2009 Food and Society
Policy Fellow, the owner of Environmental Nutrition Solutions,
the managing editor of the Journal of Hunger & Environmental
Nutrition, a member of the American Dietetic Association’s
Sustainable Food System Task Force, past chair of
the Hunger and Environmental Nutrition
Dietetic Practice Group of the American
Dietetic Association, and a member of
the Leopold Center for Sustainable
Agriculture Regional Food System
Working Group.
Expert Perspective from the Field
Organic Foods and Local Food Systems
• New Global Perspective features emphasize concepts related
to critical health and nutrition issues around the world. These
timely features, sprinkled judiciously throughout the book, also
aim to engage students with thought-provoking challenges.
Vitamin A Defi ciency
In many parts of the developing world, vitamin A defi ciency is a major public
health concern (Fig. 12-8). Recent estimates indicate that 100 to 140 million
children worldwide suffer from vitamin A defi ciency. Women of childbearing years
also are at increased risk of defi ciency, especially in impoverished areas of Africa
and Southeast Asia. In many of these areas, where HIV infection also is prevalent,
vitamin A defi ciency in pregnancy increases the likelihood of the transmission
of HIV to the developing fetus and increases the risk of maternal mortality.
Approximately 600,000 women die each year from pregnancy- and childbirth-
related causes. Many of these deaths result from complications secondary to poor
vitamin A and overall nutritional status.
11
As discussed in this chapter , vitamin A defi ciency can lead to serious
consequences, such as night blindness, total blindness, impaired growth, and an
increased incidence of infections. Due to the prevalence of vitamin A defi ciency
worldwide, it is the leading cause of pr eventable blindness in children, resulting in
250,000 to 500,000 cases annually. Approximately half of these children die within a year from severe infections, measles, diarrhea, and anemia.
11
In 1998, a partnership was formed among the World Health Organization (WHO), the United Nations Children’ s Fund (UNICEF), the Canadian
International Development Agency (CIDA), the U.S. Agency for International Development (U.S.AID), and the Micronutrient Initiative (MI) to combat
vitamin A defi ciency.
11
This coalition of international agencies, called the Vitamin A Global Initiative, has worked to decrease vitamin A defi ciency by
promoting breastfeeding, the fortifi cation of foods (e.g., sugar fortifi cation in Guatemala), and educational programs to increase home gardening of
vitamin A–rich fruits and vegetables in rural areas of Africa and Southeast Asia. WHO, UNICEF, and other international agencies also have provided
vitamin A supplements (as a complement to immunization programs) to populations at increased risk of vitamin A defi ciency. Vitamin A supplements,
which cost pennies, have been shown to decrease vitamin A–related mortality by almost 25% in these areas. Although these organizations have made
important strides in the effort to combat worldwide vitamin A defi ciency, continued nutritional and medical support is needed to eradicate global
vitamin A defi ciency. Programs to increase production and access to nutrient-rich foods (e.g., fi sh) that are native to the diets and livelihoods of the
individuals in many at-risk rural areas are food-based strategies that can help prevent nutrient defi ciencies.
Global Perspective
Clinical deficiency
Severe: subclinical
Moderate: subclinical
Mild: sporadic or high-risk
Countries categorized by degree of public health importance of vitamin A deficiency
No data: problem likely
Problem under control
Figure 12-8 Vitamin A defi ciency affects many developing countries.
Golden rice was genetically engineered to synthesize beta-carotene.
This rice was developed for use as a fortifi ed food in areas of the world
that have limited acce ss to vitamin A–rich foods.
• Each major heading in the chapter is now numbered and
crossed-referenced to the end-of-chapter summary to make it
easy to locate and prioritize important concepts.
Assessment and Evaluation of Learning
One of our primary goals as nutrition educators is to ensure that
our students leave our courses with a meaningful understanding
of the nutrition principles and concepts they need to advance their
education and improve their diets and health. Determining how
well we have met this goal requires assessment, on both the stu-
dent level and the instructor level. To this end, we have integrated
a number of assessment tools that will allow students and instruc-
tors alike to measure their success.
• Because many colleges and universities are beginning to imple-
ment student learning outcomes as a way to measure student
achievement, we have introduced student learning outcomes at
the beginning of each chapter. They have been crafted to clear-
ly delineate for students the competencies they are expected to
master in that chapter. The following are the broader, course-
wide student learning outcomes, on which the chapter level
objectives are based:
1. Identify functions and sources of nutrients.
2. Demonstrate basic knowledge of digestion, absorption, and
metabolism.
3. Apply current dietary guidelines and nutrition recommen-
dations.
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