American Cancer Society Guidelines for Nutrition Management

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American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer
Prevention: Reducing the Risk of Cancer With Healthy Food Choices and Physical
Activity
Lawrence H. Kushi, Tim Byers, Colleen Doyle, Elisa V. Bandera, Marji McCullough, Ted
Gansler, Kimberly S. Andrews, Michael J. Thun and The American Cancer Society 2006
Nutrition and Physical Activity Guidelines Advisory Committee
CA Cancer J Clin 2006;56;254-281
DOI: 10.3322/canjclin.56.5.254

This information is current as of December 11, 2010

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Guidelines on Nutrition and Physical Activity

American Cancer Society Guidelines
on Nutrition and Physical Activity for
Cancer Prevention: Reducing the
Risk of Cancer With Healthy Food
Choices and Physical Activity*

Dr. Kushi is Associate Director for
Lawrence H. Kushi, ScD; Tim Byers, MD, MPH; Colleen Doyle, MS, RD;
Etiology and Prevention Research,
Kaiser Permanente, Oakland, CA. Elisa V Bandera, MD, PhD; Marji McCullough, ScD, RD; Ted Gansler, MD, MBA;
.
Dr. Byers is Professor, Department Kimberly S. Andrews; Michael J. Thun, MD, MS; and The American Cancer Society
of Preventive Medicine and Biometrics; 2006 Nutrition and Physical Activity Guidelines Advisory Committee
and Deputy Director, University of
Colorado Cancer Center, Aurora, CO.
Ms. Doyle is Director, Nutrition and
Physical Activity, Cancer Control ABSTRACT The American Cancer Society (ACS) publishes Nutrition and Physical Activity
Science, American Cancer Society, Guidelines to serve as a foundation for its communication, policy, and community strategies
Atlanta, GA.
and ultimately, to affect dietary and physical activity patterns among Americans. These Guidelines,
Dr. Bandera is Assistant Professor,
The Cancer Institute of New Jersey, published every 5 years, are developed by a national panel of experts in cancer research, pre-
New Brunswick, NJ. vention, epidemiology, public health, and policy, and as such, they represent the most current
Dr. McCullough is Nutritional Epi- scientiﬁc evidence related to dietary and activity patterns and cancer risk. The ACS Guidelines
demiologist, American Cancer Society,
Atlanta, GA. include recommendations for individual choices regarding diet and physical activity patterns,

Dr. Gansler is Director of Medical but those choices occur within a community context that either facilitates or interferes with
Content, Health Promotions, American healthy behaviors. Community efforts are essential to create a social environment that pro-
Cancer Society, Atlanta, GA.
motes healthy food choices and physical activity. Therefore, this committee presents one key
Ms. Andrews is a Research Assoc-
iate, Cancer Control Science, American recommendation for community action to accompany the four recommendations for individ-
Cancer Society, Atlanta, GA. ual choices to reduce cancer risk. This recommendation for community action recognizes that
Dr. Thun is Vice President, Epidem- a supportive social environment is indispensable if individuals at all levels of society are to have
iology and Surveillance Research,
American Cancer Society, Atlanta, GA. genuine opportunities to choose healthy behaviors. The ACS Guidelines are consistent with

This article is available online at guidelines from the American Heart Association and the American Diabetes Association for
http://CAonline.AmCancerSoc.org the prevention of coronary heart disease and diabetes, as well as for general health promo-
tion, as defined by the Department of Health and Human Services’ 2005 Dietary Guidelines
for Americans. (CA Cancer J Clin 2006;56:254–281.) © American Cancer Society, Inc., 2006.

THE IMPORTANCE OF WEIGHT CONTROL, PHYSICAL ACTIVITY,
AND DIET IN CANCER PREVENTION

For the great majority of Americans who do not use tobacco, weight control, dietary choices, and levels of phys-
ical activity are the most important modifiable determinants of cancer risk.1–3 Evidence suggests that one-third of
the more than 500,000 cancer deaths that occur in the United States each year can be attributed to diet and physical
activity habits, including overweight and obesity, while another third is caused by exposure to tobacco products.
Although genetic inheritance inﬂuences the risk of cancer, and cancer arises from genetic mutations in cells, most of
the variation in cancer risk across populations and among individuals is due to factors that are not inherited.4 Behaviors

*The following report was approved by the American Cancer Society National Board of Directors on May 19, 2006.

254 CA A Cancer Journal for Clinicians

CA Cancer J Clin 2006;56:254–281

such as avoiding exposure to tobacco products, factors were considered more credible than those
maintaining a healthy weight, staying physically that failed to meet these criteria.
active throughout life, and consuming a healthy For many issues concerning nutrition and
diet can substantially reduce one’s lifetime risk of cancer, the evidence is not definitive, either
developing cancer.5–8 These same behaviors are because the published results are inconsistent,
also associated with decreased risk of developing and/or because the methods of studying nutri-
cardiovascular disease. Although these healthy tion and chronic disease in human populations
choices are made by individuals, they may be are still in evolution. Part of the uncertainty has

facilitated or impeded by the social and physical resulted from studies that focus on specific nutri-
environment in which people live. ents or foods in isolation, thereby oversimplify-
ing the complexity of foods and dietary patterns;
the importance of dose, timing, and duration of
OVERVIEW OF THE GUIDELINES exposure; and the large variations in nutritional
status among human populations. Nutritional
The ACS publishes Nutrition and Physical research is equally challenging in RCTs, gen-
Activity Guidelines to advise health care pro- erally considered the gold standard for scientific
fessionals and the general public about dietary conclusions. Studies may fail to find an effect if
and other lifestyle practices that reduce cancer the intervention begins too late in life, is too
risk.9,10 These Guidelines, updated in 2006 by small, or if the follow up is too short for a ben-
the ACS Nutrition and Physical Activity Guide- efit to appear. No single trial can resolve all of the
lines Advisory Committee, are based on synthe- questions that are relevant to the potential effects
sis of the current scientific evidence on diet and of nutrition throughout the lifespan. Moreover,
physical activity in relation to cancer risk. The many important questions about how diet, phys-
Committee reviewed evidence from human pop- ical activity, and obesity relate to cancer cannot
ulation studies and laboratory experiments pub- presently be addressed in RCTs. For example,
lished since the last release of the Guidelines in randomized trials of weight loss in relation to
2001. The Committee also considered other cancer risk are severely constrained by the cur-
comprehensive reviews of diet, obesity, and phys- rent lack of effective behavioral or pharmaco-
ical inactivity in relation to cancer. For some logic approaches to help people lose weight and
aspects of nutrition, the most thorough review sustain a healthy weight. The cost and difficulty
was the 1997 World Cancer Research Fund/ of randomized trials to determine the long-term
American Institute for Cancer Research mono- consequences of interventions that begin in
graph; for others, such as physical activity, obe- infancy and extend for many years preclude long-
sity, and fruit and vegetable consumption, there term experimental interventions. Interventions
have been more recent comprehensive re- are ethical only if they can plausibly improve the
views.3,11,12 In weighing the evidence from ran- health of the participants. Although it might be
domized controlled trials (RCTs), the Committee easier to motivate people to increase their weight
considered the findings in relation to the design by consuming more calories and/or fat and by
of the trial, the specific question being addressed, decreasing their physical activity, such studies are
and the importance of the trial results in the clearly unethical.
context of other evidence from human popu- Inferences about the many complex interre-
lations. Prospective cohort studies were weighted lationships among body weight, physical activ-
more heavily than case-control studies, espe- ity, diet, and cancer risk are therefore based, for
cially when results were available from several the most part, on a combination of clinical tri-
cohorts. Population-based case-control studies als and observational studies coupled with advanc-
with at least 200 cases of cancer were consid- ing understanding of the biology of cancer. These
ered more informative than smaller or hospital- Guidelines are based on the totality of evidence
based case-control studies. Studies that adjusted from all sources, taking into account both the
for total energy intake, considered other dietary potential health benefits and possible risks from
factors, and controlled for other known risk the intervention. No diet or lifestyle pattern can

Volume 56 • Number 5 • September/October 2006 255


TABLE 1 American Cancer Society (ACS) Guidelines on Nutrition and Physicial Activity for Cancer Prevention

ACS Recommendations for Individual Choices
Maintain a healthy weight throughout life.
• Balance caloric intake with physical activity.
• Avoid excessive weight gain throughout the life cycle.
• Achieve and maintain a healthy weight if currently overweight or obese.
Adopt a physically active lifestyle.
• Adults: engage in at least 30 minutes of moderate to vigorous physical activity, above usual activities, on 5 or more days of the week.

Forty-five to 60 minutes of intentional physical activity are preferable.
• Children and adolescents: engage in at least 60 minutes per day of moderate to vigorous physical activity at least 5 days per week.
Consume a healthy diet, with an emphasis on plant sources.
• Choose foods and beverages in amounts that help achieve and maintain a healthy weight.
• Eat five or more servings of a variety of vegetables and fruits each day.
• Choose whole grains in preference to processed (refined) grains.
• Limit consumption of processed and red meats.
If you drink alcoholic beverages, limit consumption.
• Drink no more than one drink per day for women or two per day for men.

ACS Recommendations for Community Action
Public, private, and community organizations should work to create social and physical environments that support the adoption and
maintenance of healthful nutrition and physical activity behaviors.
• Increase access to healthful foods in schools, worksites, and communities.
• Provide safe, enjoyable, and accessible environments for physical activity in schools, and for transportation and recreation in communities.

guarantee full protection against any disease; the levels of society are to have genuine opportuni-
potential health benefit represents a decreased ties to choose healthy behaviors.
likelihood that the disease will occur, not a guar-
antee of total protection. These Guidelines pro-
vide a concise and understandable summary of AMERICAN CANCER SOCIETY GUIDELINES
the existing scientific information about weight FOR NUTRITION AND PHYSICAL ACTIVITY
control, physical activity, and nutrition in rela- Recommendations for Community Action
tion to cancer. The ACS Guidelines are consis-
tent with guidelines established for cancer Social, economic, and cultural factors strongly
prevention by other countries 8; those from the influence individual choices about diet and phys-
American Heart Association and American ical activity. Although many Americans would like
Diabetes Association for the prevention of coro- to adopt a healthy lifestyle, many encounter sub-
nary heart disease and diabetes 13,14; as well as for stantial barriers that make it difficult to follow diet
general health promotion, as defined by the 2005 and activity guidelines. Indeed, current trends
Dietary Guidelines for Americans.15 toward increasing portion sizes,16–19 as well as
In addition to recommendations regarding the consumption of high-calorie convenience
individual choices related to weight control, foods, beverages, and restaurant meals, and declin-
physical activity, and diet, the ACS Guidelines ing levels of physical activity are contributing to
underscore what communities can and should an obesity epidemic among Americans of all ages
do to facilitate healthy eating and physical activ- and across all population segments.15,20,21 Longer
ity behaviors (Table 1). Community efforts are workdays and more households with multiple
essential to create a social environment that pro- wage earners reduce the amount of time avail-
motes healthy food choices and physical activ- able for preparation of meals, with a resulting
ity. Thus, the recommendation for community shift toward increased consumption of high-
action recognizes that a supportive social envi- calorie food outside the home—frequently less
ronment is indispensable if individuals at all nutritious than foods prepared at home.22 Large



portion sizes and calorie-dense foods are used approaches that produced much larger reductions
extensively in marketing by restaurants, supermar- in cigarette smoking among children and adults,
kets, and food companies.16–19 Reduced leisure beginning in the mid-1980s. These included
time, increased reliance on automobiles for trans- restrictions on cigarette advertising, increases in the
portation, and increased availability of electronic price of tobacco products through taxation, laws
entertainment and communications media all preventing exposure to secondhand smoke in
contribute to reduced physical activity. 20,21 public places, and restrictions on the access of
Increasing evidence indicates associations between children to tobacco products. Only recently have

the built environment and obesity and physical communities begun to consider policy approaches
activity levels.23,24 Poor access to sidewalks, parks, that might promote better nutrition and physi-
and recreation facilities is associated with greater cal activity at the population level. Public, pri-
obesity risk,25 whereas neighborhoods that facil- vate, and community organizations are now
itate walking and safe physical recreation have considering policy measures and strategies that
lower obesity prevalence.23 could help individuals choose healthier patterns
The increase in obesity and physical inactiv- of nutrition and physical activity (Table 1).
ity is of particular concern for a number of pop-
ulation groups, including children, who are Recommendations for Individual Choices
establishing lifetime behavioral patterns that
affect health, and lower-income populations, Approximately two-thirds of Americans are
who face additional problems because nearby overweight or obese. The percentage of children,
stores often lack affordable and attractive healthy adolescents, and adult men who are overweight
foods, and safety concerns limit opportunities for or obese has continued to increase through 2004,
physical activity. although the trend has now stabilized in adult
Facilitating improved diet and increased phys- women.26 In addition, many Americans are less
ical activity patterns in communities will require physically active than is optimal for health. There
multiple strategies and bold action, ranging from is no longer serious medical debate about whether
the implementation of community, worksite, and obesity, the prevalence of which has doubled in
other health promotion programs to policies that the last 25 years, constitutes a major health prob-
affect community planning, transportation, school- lem in the United States, increasing the risk of
based physical education, and food services. Par- several cancers as well as of coronary heart dis-
ticular efforts will be needed to ensure that all ease, type 2 diabetes, and other medical prob-
population groups have access to healthy food lems. For most people in the United States, weight
choices and opportunities for physical activity. gain results from a combination of excessive caloric
Public and private organizations at local, state, intake and inadequate physical activity. Thus,
and national levels will need to develop new poli- while there continues to be genuine scientific
cies and to reallocate or expand resources to facil- uncertainty about how speciﬁc aspects of excess
itate necessary changes. Health care professionals adiposity, excessive energy intake, and physical
and community leaders, in particular, have new inactivity relate to cancer, there is no debate about
opportunities to provide leadership and to pro- whether these constitute a serious and growing
mote policy changes in their communities. health problem. These Guidelines therefore empha-
Lessons learned from the tobacco epidemic size the importance of maintaining a healthy body
exemplify the power of social context in chang- weight, adopting a physically active lifestyle, and
ing health behaviors. Adult per-capita cigarette consuming a healthy diet, particularly within the
consumption increased steeply from 1910 until context of weight management.
1964, when the ﬁrst US Surgeon General Report
publicized the health hazards of smoking. However, 1. Maintain a Healthy Weight Throughout Life.
public education alone produced only a gradual
decrease in cigarette consumption from 1964 • Balance caloric intake with physical activity.
through the early 1980s. It was the subsequent • Avoid excessive weight gain throughout the
introduction of community-wide policy life cycle.



TABLE 2 Adult BMI Chart

BMI 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Height Weight in Pounds

4 10 91 96 100 105 110 115 119 124 129 134 138 143 148 153 158 162 167
4 11 94 99 104 109 114 119 124 128 133 138 143 148 153 158 163 168 173
5 97 102 107 112 118 123 128 133 138 143 148 153 158 163 168 174 179
5 1 100 106 111 116 122 127 132 137 143 148 153 158 164 169 174 180 185
5 2 104 109 115 120 126 131 136 142 147 153 158 164 169 175 180 186 191

5 3 107 113 118 124 130 135 141 146 152 158 163 169 175 180 186 191 197
5 4 110 116 122 128 134 140 145 151 157 163 169 174 180 186 192 197 204
5 5 114 120 126 132 138 144 150 156 162 168 174 180 186 192 198 204 210
5 6 118 124 130 136 142 148 155 161 167 173 179 186 192 198 204 210 216
5 7 121 127 134 140 146 153 159 166 172 178 185 191 198 204 211 217 223
5 8 125 131 138 144 151 158 164 171 177 184 190 197 203 210 216 223 230
5 9 128 135 142 149 155 162 169 176 182 189 196 203 209 216 223 230 236
5 10 132 139 146 153 160 167 174 181 188 195 202 209 216 222 229 236 243
5 11 136 143 150 157 165 172 179 186 193 200 208 215 222 229 236 243 250
6 140 147 154 162 169 177 184 191 199 206 213 221 228 235 242 250 258
6 1 144 151 159 166 174 182 189 197 204 212 219 227 235 242 250 257 265
6 2 148 155 163 171 179 186 194 202 210 218 225 233 241 249 256 264 272
6 3 152 160 168 176 184 192 200 208 216 224 232 240 248 256 264 272 279

Healthy Weight Overweight Obese

Source: US Department of Health and Human Services, National Institutes of Health, National Health, Lung, and Blood
Institute. The Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults:
Evidence Report. September 1998 [NIH pub. No. 98-4083].

• Achieve and maintain a healthy weight if cur- growth, such as insulin-like growth factor-1;
rently overweight or obese. and proteins that make hormones more or less
available to tissues, such as sex hormone-bind-
Body Weight and Cancer Risk
ing globulin. 3 Overweight and obesity may
In the United States, overweight and obesity increase risk of adenocarcinoma of the esopha-
contribute to 14% to 20% of all cancer-related gus by increasing risk of gastroesophageal reflux
mortality.27 Overweight and obesity are clearly disease and Barrett’s esophagus.3
associated with increased risk for developing Most research on energy imbalance and can-
many cancers, including cancers of the breast in cer focuses on increased risks associated with
postmenopausal women, 3,27–33 colon, endo- overweight and obesity. Recently, studies explor-
metrium, adenocarcinoma of the esophagus, and ing intentional weight loss suggest that losing
kidney. Evidence is highly suggestive that obe- weight may reduce the risk of breast cancer.34–38
sity also increases risk for cancers of the pan- Surgery to treat morbid obesity and short-term
creas, gallbladder, thyroid, ovary, and cervix, and intentional weight loss have been shown to
for multiple myeloma, Hodgkin lymphoma, and improve insulin sensitivity and biochemical meas-
aggressive prostate cancer.3,27–33 These findings ures of hormone metabolism, which have been
are supported by both epidemiologic studies in postulated to contribute to the relationship
humans and other research.3,27–33 Overweight between obesity and certain cancers. The sur-
and obesity are thought to affect risk of these gical removal of intra-abdominal fat has also
cancers through a variety of mechanisms, some been shown to reduce the metabolic syndrome.
of which are specific to particular cancer types. Even though our knowledge about the relation-
These mechanisms include effects on fat and ship between weight loss and cancer risk is incom-
sugar metabolism; immune function; levels of plete, individuals who are overweight or obese
several hormones, including insulin and estra- should be encouraged and supported in their
diol; factors that regulate cell proliferation and efforts to reduce weight.



Achieving and Maintaining a Healthy Weight people.15 The healthiest way to reduce caloric
intake is to reduce intake of added sugars, sat-
A healthy weight depends on a person’s height,
urated and trans fats, and alcohol, which all pro-
so recommendations for a healthy weight are
vide substantial calories, but few or no essential
often expressed in terms of a body mass index
nutrients. Caloric intake can be reduced by
(BMI) (Table 2). BMI is calculated as body weight
decreasing the size of food portions (see standard
in kilograms divided by height in meters, squared.2
serving sizes [Table 3]) and limiting the intake
Exact cutoffs for a healthy weight are somewhat
of foods and beverages that are high in calories,
arbitrary, but for most Americans, experts con-

fat, and/or refined sugars, and which provide
sider a BMI within the range of 18.5 to 25.0
few nutrients (eg, fried foods, cookies, cakes,
kg/m2 to be healthy, a BMI between 25.0 and
candy, ice cream, and soft drinks). Such foods
29.9 to be overweight, and a BMI of 30.0 and
and beverages should be replaced with choices
over to be obese. Individuals should strive to main-
like vegetables and fruits, whole grains, beans,
tain healthy weights as illustrated in Table 2.
and lower-calorie beverages.39 People should
The way to achieve a healthy body weight
be aware that meals served in fast-food estab-
is to balance energy intake (food and beverage
lishments and restaurants typically exceed the
intake) with energy expenditure (physical activ-
portion sizes needed to meet recommended
ity).3,15 Excess body fat can be reduced by reduc-
daily caloric intake and are often high in hidden
ing caloric intake and increasing physical activity.
fats.39 They also are often low in vegetables,
For most adults a reduction of 50 to 100 calo-
fruits, whole grains, and beans.22 Monitoring
ries per day may prevent gradual weight gain,
food intake and physical activity has been shown
whereas a reduction of 500 calories or more per
to be effective in weight management.19,39,40
day is a common initial goal in weight loss pro-
The health of young people, and the adults
grams. Similarly, up to 60 minutes of moder-
they will become, is critically linked to the estab-
ate to vigorous intensity physical activity per
lishment of healthy behaviors in childhood.41
day may be needed to prevent weight gain, but
Risk factors such as excess weight gain, unhealthy
as much as 60 to 90 minutes of moderate inten-
dietary patterns, and physical inactivity during
sity physical activity per day may help to sus-
childhood and adolescence can result in increased
tain weight loss for previously overweight
risk of developing cancer, cardiovascular disease,
diabetes, hypertension, and osteoporosis later in
TABLE 3 What Counts as a Serving life.41 Children who adopt healthy lifestyle habits
at an early age are more likely to continue these
Fruits • 1 medium apple, banana, orange
• 1/2 cup of chopped, cooked, or behaviors throughout life. About half of young-
canned fruit sters who are overweight as children will remain
• 1/2 cup of 100% fruit juice overweight in adulthood42; 70% of those who
Vegetables • 1 cup of raw leafy vegetables are overweight by adolescence will remain over-
• 1/2 cup of other cooked or raw weight as adults.18 For these reasons, efforts to
vegetables, chopped
• 1/2 cup of 100% vegetable juice establish healthy weight and patterns of weight
gain should begin in childhood.
Grains • 1 slice bread
• 1 ounce ready-to-eat cereal
• 1/2 cup of cooked cereal, rice, pasta 2. Adopt a Physically Active Lifestyle.
Beans and nuts • 1/2 cup cooked dry beans
• 2 tablespoons peanut butter • Adults: engage in at least 30 minutes of mod-
• 1/3 cup nuts
erate to vigorous physical activity, above usual
Dairy foods • 1 cup milk or yogurt activities, on 5 or more days of the week.
and eggs • 1 1/2 ounces of natural cheese
• 2 ounces processed cheese
Forty-ﬁve to 60 minutes of intentional phys-
• 1 egg ical activity are preferable.
Meats 2–3 ounces of cooked lean meat, • Children and adolescents: engage in at least
poultry, fish 60 minutes per day of moderate to vigorous
physical activity at least 5 days per week.



Benefits of Physical Activity Recommended Amount of Total
Scientific evidence indicates that physical and Intentional Activity
activity may reduce the risk of several types of Although the optimal intensity, duration, and
cancer, including cancers of the breast, colon, frequency of physical activity needed to reduce
prostate, and endometrium.3,29,43 Although sci- cancer risk are unknown, evidence suggests that
entific evidence for many other cancers is lack- at least 30 minutes of moderate to vigorous ac-
ing, associations may exist. Physical activity acts tivity, in addition to usual activities done through-
in a variety of ways to impact cancer risk. 44 out the day, can help reduce cancer risk. Evidence

Regular and intentional physical activity helps is accumulating that 45 to 60 minutes on 5 or
maintain a healthy body weight by balancing more days of the week may be optimal to reduce
caloric intake with energy expenditure.45 Other risk of cancers of the colon and breast.3 There
mechanisms by which physical activity may is limited evidence regarding whether physical
help to prevent certain cancers may involve activity is most protective if done in a single
both direct and indirect effects, including reg- session or in increments throughout the day,
ulating sex hormones, insulin, prostaglandins, but it is reasonable to assume that benefit can
and various beneficial effects on the immune be accumulated in separate sessions of 20 to 30
system.3,46,47 The benefits of a physically active minutes each.
lifestyle far exceed reducing the risk of cancer Data suggest that 60 minutes of moderate to
and provide other important health benefits,3 vigorous activity on 5 or more days per week
including associations with reduced risk of other helps to prevent weight gain and obesity.15,50 By
chronic diseases, such as heart disease, diabetes, helping to maintain weight, physical activity for
osteoporosis, and hypertension.48 60 minutes on 5 or more days of the week may
have an indirect effect on reducing the risk of
Types of Activity developing obesity-related cancers.51–55 Apart
Usual activities are those that are performed from effects on obesity, physical activity appears
on a regular basis as part of one’s daily routine. to have other effects on reducing the risk of can-
These activities include those performed at work cers of the colon and breast, even when activity
(such as walking from the parking garage to the is not initiated until later in life.55
office), at home (such as climbing a flight of For people who are largely inactive or just
stairs), as well as those considered activities of beginning a physical activity program, a grad-
daily living (such as dressing and bathing). They ual increase to 30 minutes per day of moderate
are typically of low intensity and short duration. intensity physical activity on at least 5 days per
Intentional activities are those that are done in week will provide substantial cardiovascular ben-
addition to these usual activities. These activities efits.56,57 After this duration is achieved, increas-
are often planned and often done at leisure, for ing intensity to vigorous levels may further
exercise, for fitness, or transportation to inten- improve health benefits for those individuals
tionally supplement other routine activities. who are able to exercise at this intensity. Most
These activities range from a bike ride or a run children and young adults can safely engage in
to including more purposeful physical activity moderate physical activity without consulting
into the day, such as walking to use public trans- their physicians. However, men older than 40
portation instead of driving. Moderate activi- years, women older than 50 years, and people
ties are those that require effort equivalent to a with chronic illnesses and/or established cardio-
brisk walk.49 Vigorous activities generally engage vascular risk factors should consult their physi-
large muscle groups and cause a noticeable cians before beginning a vigorous physical activity
increase in heart rate, breathing depth and fre- program. Stretching and warm-up periods before
quency, and sweating. 49 These activities can be and after activity can reduce the risk of muscu-
performed in a variety of settings: occupational, loskeletal injuries and muscle soreness.
recreational, in the home or garden, and with Individuals who are already active at least 30
friends or family.49 minutes on most days of the week should strive



TABLE 4 Examples of Moderate and Vigorous Intensity Physical Activities

Moderate Intensity Activities Vigorous Intensity Activities

Exercise and leisure Walking, dancing, leisurely bicycling, ice and roller Jogging or running, fast bicycling, circuit weight
skating, horseback riding, canoeing, yoga training, aerobic dance, martial arts, jumping
rope, swimming
Sports Volleyball, golfing, softball, baseball, badminton, Soccer, field or ice hockey, lacrosse, singles
doubles tennis, downhill skiing tennis, racquetball, basketball, cross-country
skiing
Home activities Mowing the lawn, general yard and garden maintenance Digging, carrying and hauling, masonry,

carpentry
Occupational activity Walking and lifting as part of the job (custodial work, Heavy manual labor (forestry, construction,
farming, auto or machine repair) firefighting)

to accumulate 60 minutes of moderate or greater to vigorous intensities for at least 60 minutes per
intensity activity on most days of the week. day on 5 or more days per week.60,61 Activities
Selected examples of moderate and vigorous should be developmentally appropriate, enjoy-
activities are provided in Table 4. able, and varied,59 including sports and fitness
Adopting a physically active lifestyle involves activities in school, at home, and in the com-
making deliberate decisions and changing munity.62 Because children and adolescents spend
lifestyle behaviors to select active rather than a significant portion of their days in schools, the
sedentary behavior. To enhance the ability of availability of routine, high-quality physical edu-
individuals to adopt a more active lifestyle, both cation programs is a critically important and rec-
communities and individuals need to imple- ognized way of increasing physical activity among
ment changes (see Recommendation for Community youth.62 To help achieve activity goals, daily
Action). Ideas to reduce sedentary behavior are physical education programs and activity breaks
suggested in Table 5. should be provided for children at school, and tel-
Physical activity plays an important role in evision viewing and computer game time should
children’s and adolescents’ health and well-being be minimized at home.
and has important physical, mental, and social Although the health benefits of physical activ-
benefits.15,58,59 Because one of the best predic- ity in preventing cancer and other chronic dis-
tors of adult physical activity is activity level dur- eases are facilitated by the development of healthy
ing childhood and adolescence, and because activity patterns in childhood, benefit seems to
physical activity plays a critical role in weight accumulate over the course of a lifetime.6 There-
maintenance, children and adolescents should be fore, increasing the level of physical activity at
encouraged to be physically active at moderate any age can provide important health benefits
and may reduce the risk of some cancers.
TABLE 5 Suggested Ways to Reduce 3. Consume a Healthy Diet, with an Emphasis
Sedentary Behavior on Plant Sources.

• Use stairs rather than an elevator. Choose foods and beverages in amounts that
• If you can, walk or bike to your destination.
help achieve and maintain a healthy weight.
• Exercise at lunch with your coworkers, family, or friends.
• Take an exercise break at work to stretch or take a quick walk. • Become familiar with standard serving sizes,
• Walk to visit coworkers instead of sending an e-mail. and read food labels to become more aware
• Go dancing with your spouse or friends. of actual servings consumed.
• Plan active vacations rather than only driving trips.
• Wear a pedometer every day and increase your daily steps. • Eat smaller portions of high-calorie foods. Be
• Join a sports team. aware that “low-fat” or “nonfat” does not mean
• Use a stationary bicycle or treadmill while watching TV. “low-calorie,” and that low-fat cakes, cook-
• Plan your exercise routine to gradually increase the days per
week and minutes per session.
ies, and similar foods are often high in calories.
• Spend time playing with your kids. • Substitute vegetables, fruits, and other low-
calorie foods and beverages for calorie-dense



foods and beverages such as French fries, dietary pattern as outlined, with special empha-
cheeseburgers, pizza, ice cream, doughnuts sis placed on controlling total caloric intake to
and other sweets, and regular sodas. help achieve and maintain a healthy weight.
• When you eat away from home, choose food
Choosing Foods and Beverages in Amounts
low in calories, fat, and sugar, and avoid large
portion sizes. That Achieve and Maintain a Healthy Weight
Eat five or more servings of vegetables and Most people cannot maintain a healthy weight
fruits each day. without limiting caloric intake while maintain-
• Include vegetables and fruits at every meal and

ing regular physical activity. Unfortunately, cur-
for snacks. rent trends indicate that the largest percentage
• Eat a variety of vegetables and fruits each day. of calories in the American diet comes from
• Limit French fries, chips, and other fried veg- foods high in fat, sugar, and refined carbohy-
etable products. drates.66 Consuming a varied diet that empha-
• Choose 100% juice if you drink vegetable or sizes plant foods may help to displace these
fruit juices. calorie-dense foods. Limiting portion sizes, espe-
Choose whole grains in preferences to proc- cially of these types of foods, is another impor-
essed (refined) grains and sugars. tant strategy to reduce total caloric intake.
• Choose whole grain rice, bread, pasta, and Replacing dietary fat with foods that are high
cereals. in calories from added sugar and other refined car-
• Limit consumption of refined carbohydrates, bohydrates does not protect against overweight
including pastries, sweetened cereals, and other or obesity. The decrease in fat intake and increase
high-sugar foods. in refined carbohydrates that occurred in the
Limit consumption of processed and red meats. United States between 1977 and 1995 coincided
• Choose fish, poultry, or beans as an alternative with an 8% increase in the prevalence of obe-
to beef, pork, and lamb. sity.67,68 Many processed foods, including soft
• When you eat meat, select lean cuts and eat drinks and fruit drinks, presweetened cereals,
smaller portions. pastries, candies, and syrups, contain large
• Prepare meat by baking, broiling, or poaching amounts of added sugars. These added sugars
rather than by frying or charbroiling. come in many forms, such as glucose, high-
The scientific study of nutrition and cancer is fructose corn syrup, fruit juice concentrates, and
highly complex, and many important questions honey. Consuming products high in these added
remain unanswered. For example, it is not sugars adds little nutrient value to the diet, con-
presently completely understood how energy tributes to excess energy intake, and may con-
imbalance or how single or combined nutrients tribute to insulin resistance, alterations in the
or foods affect one’s risk of specific cancers. In amount and distribution of body fat, and increased
addition, many dietary factors and lifestyle prac- concentrations of growth factors that may pro-
tices tend to correlate with each other; for exam- mote the growth of cancers.
ple, people who consume a diet high in vegetables
Vegetables and Fruits
and fruits also tend to eat less meat and be more
physically active.63 Foods and nutrients may have Vegetables (including legumes) and fruits are
additive or synergistic effects on health and need complex foods, each containing numerous po-
to be considered in the context of the total diet. tentially beneficial vitamins, minerals, fiber,
Studies have shown that individuals whose diets carotenoids, and other bioactive substances, such
are very low in vegetables and fruits and whole as flavonoids, terpenes, sterols, indoles, and phe-
grains, and high in processed and red meats, tend nols that may help prevent cancer.11 Greater con-
to have an increased risk of some of the most sumption of vegetables and fruits is associated
common types of cancers.64,65 Until more is with decreased risk of lung, esophageal, stomach,
known about the specific components of diet and colorectal cancer.11 For other cancers, evi-
that influence cancer risk, the best advice is to dence is either limited or inconsistent, although
consume whole foods following an overall healthy the role of vegetables and fruits may indirectly



influence cancer risk via their effects on energy duration, and timing of a single nutrient interven-
intake. Intervention studies of dietary patterns, tion, based on evidence derived from broader
including high consumption of vegetables and observational data on whole foods, like vegeta-
fruits, have not been associated with a reduced bles and fruits. Notable examples are the four
risk of developing adenomatous polyps 69 or randomized trials of beta carotene for the pre-
colon cancer,70 but the degree of adherence to vention of lung cancer, which were initiated
and achievement of study goals over several because many observational epidemiologic stud-
years among free-living individuals may limit ies had indicated a lower risk of lung cancer in per-

interpretability. Although the strength of the sons eating foods high in beta carotene.74,75 In
cumulative evidence that total intake of vegeta- two of these trials, the individuals taking high-dose
bles and/or fruits decreases cancer risk has weak- beta carotene supplements developed lung can-
ened in recent years, the totality of the evidence cer at higher rates than those taking a placebo.76–78
remains strong for a risk reduction associated Although there has been considerable evidence
with vegetable and fruit consumption at a vari- from observational studies that people consum-
ety of cancer sites.11 There is ongoing research ing more beta carotene from foods were at reduced
on the potential benefits of particular vegetables risk for lung cancer, these findings support the
and fruits, or groups of these, including dark idea that beta carotene may be only a proxy for
green and orange vegetables, cruciferous veg- other single nutrients or combinations of nutri-
etables (eg, cabbage, broccoli, cauliflower, Brussels ents found in whole foods, and that taking a sin-
sprouts), soy products, legumes, Allium vegeta- gle nutrient in large amounts can be harmful, at
bles (onions and garlic), and tomato products. least for some subgroups of the population.
In addition to providing nutrients that may A number of different recommendations
be beneficial in reducing cancer risk, vegeta- have been made to encourage Americans to
bles and fruits may also contribute to weight increase the number of servings of vegetables and
maintenance, although the epidemiologic evi- fruits they consume.13,15,79 Despite these rec-
dence supporting such an association is lim- ommendations, intake of these foods remains
ited.71 Some evidence suggests that individuals low among adults and children.80,81 This may be
who eat more vegetables and fruits have less due to several reasons, including lack of access
weight gain and lower risk of developing obe- to affordable produce, preparation time, and
sity over time.72 Intake of vegetables and fruits taste preferences.82–85
may be particularly important if their consump- Eating a diet rich in vegetables and fruits
tion replaces other, more calorically dense foods may reduce cancer risk both directly and indi-
as a strategy for maintaining a healthy weight. rectly by contributing to maintenance of a healthy
For that reason, consumption of low-calorie, weight.11,71 Vegetable and fruit consumption has
whole vegetables and fruits should be encour- also been found to be associated with reduced risk
aged. Consumption of vegetables and fruits that of other chronic diseases, particularly cardiovas-
are fried (eg, French fries) or consumed with cular disease, an important contributor to over-
calorically dense sauces (eg, broccoli with cheese all morbidity and mortality in the United
sauce), or high-calorie fruit juices and/or drinks States.13,86–88 For cancer risk reduction, the rec-
does not help achieve this objective. ommendation is to consume at least five serv-
Evidence that vegetable and fruit consump- ings of a variety of vegetables and fruits each
tion reduces cancer risk has led to attempts to day; however, for overall health, the ACS supports
isolate specific nutrients and administer them as the recommendation to consume higher levels,
supplements, sometimes in very high doses.73 depending on calorie needs, as stated in the US
Most of these attempts have been unsuccessful Department of Health and Human Services’
in preventing cancer or its precursor lesions, and Dietary Guidelines for Americans.15
in some cases, have had adverse effects.73 Some
Whole Grains
of this may be due to the methodologic chal-
lenges of studying nutrients in RCTs for can- Grains such as wheat, rice, oats, and barley,
cer; investigators must often select exact doses, and the foods made from them, are an important



part of an overall healthful diet. Whole grain formation of nitrosamines that can damage DNA.
foods, which are those made from the entire It is also possible that the fat content in meat con-
grain seed, are relatively low in caloric density and tributes to risk. For example, foods that are high
can contribute to maintaining energy balance.15,89 in fat increase the concentration of secondary bile
In addition, whole grains are higher in fiber, acids and other compounds in the stool that could
certain vitamins, and minerals than processed be carcinogens or promoters of carcinogenesis.
(refined) flour products. Some of these vitamins Although meats are good sources of high-
and minerals have been associated with lower quality protein and can supply many impor-

risk of cancer.90 The association between whole tant vitamins and minerals, they remain major
grain foods and different types of cancer has been contributors of total fat, saturated fat, and cho-
inconsistent, however, possibly because the ques- lesterol in the American diet.100 The recommen-
tionnaires used in these studies to assess dietary dation is to limit consumption of processed and
intake were generally not specifically designed to red meats. To accomplish this, choose lean meats
assess whole grain consumption, which in most and smaller portions, and use meat as a side
cases resulted in incomplete assessments. dish rather than as the focus of a meal. Legumes
Consumption of high-fiber foods is associ- are especially rich in nutrients that may pro-
ated with a lower risk of several chronic diseases, tect against cancer and can be a healthier source
including diabetes, cardiovascular disease, and of protein than red meats. Although cooking
diverticulitis.15 Consuming high-fiber foods, meat at high temperatures, such as in grilling or
such as legumes and whole grain breads, cereals, frying, can produce potential carcinogens, care
rice, and pasta, is therefore highly recommended, should be taken to cook meat thoroughly to
even though data for an association between destroy harmful bacteria and parasites, but to
fiber and cancer risk are limited.69,91,92 Because avoid charring.
the benefits of whole grain foods may derive
4. If You Drink Alcoholic Beverages,
from their other nutrients as well as fiber, it is
Limit Consumption
preferable to consume whole grain foods rather
than fiber supplements. People who drink alcohol should limit their
intake to no more than two drinks per day for
Processed and Red Meats
men and one drink a day for women.15 The rec-
Many epidemiologic studies have examined ommended limit is lower for women because of
the association between cancer and the con- their smaller body size and slower metabolism of
sumption of red meats (defined as beef, pork, alcohol. A drink of alcohol is defined as 12 ounces
or lamb) and processed meats (cold cuts, bacon, of beer, 5 ounces of wine, or 1.5 ounces of
hot dogs, etc.). Current evidence supports an 80-proof distilled spirits. Alcohol consumption is
increased risk of cancers of the colon and/or an established cause of cancers of the mouth,
rectum93–96 and prostate.97,98 More limited evi- pharynx, larynx, esophagus, and liver.5,101 For
dence exists for other sites. Studies that have each of these cancers, risk increases substantially
examined red meat and processed meat sepa- with intake of more than two drinks per day.5,101
rately suggest that risks associated with processed Alcohol consumption combined with tobacco
meat may be slightly greater than red meat,93–95,98 increases the risk of cancers of the mouth, lar-
but the consumption of both should be limited. ynx, and esophagus far more than the independ-
Meat contains several constituents that could ent effect of either dr inking or smoking. 5
increase the risk of cancer.97,99 Mutagens and Extensive evidence also implicates alcohol con-
carcinogens (heterocyclic amines and polycyclic sumption as a cause of cancer of the breast,102–104
aromatic hydrocarbons) are produced by cook- and probably colon and rectum cancer. 5,105
ing meat at high temperatures and/or by char- Regular consumption of more than one drink per
coal grilling. The iron content (heme) in red day has been associated with an increased risk
meat may generate free radicals in the colon that of breast cancer in women.103 The mechanism
damage DNA. Substances used to process meat by which alcohol is related to breast cancer is
(nitrates/nitrites and salt) contribute to the not known, but it may be due to alcohol-induced



increases in circulating estrogens or other hor- chemicals. Limited evidence suggests that drink-
mones in the blood, reduction of folate levels, or ing more fluids may lower the risk of bladder
to a direct effect of alcohol or its metabolites on cancer, as may eating more vegetables.111
breast tissue. Reducing alcohol consumption
may be an important way for many women to Brain Tumors
reduce their risk of breast cancer. In particular,
women with a low intake of folate may be more There are no known nutritional risk factors
susceptible to the increase in breast cancer risk for brain tumors at this time.

from alcohol.106–109 Overall, the evidence seems
to indicate that total alcohol consumption is the Breast Cancer
important factor, not the type of alcoholic bev-
erage consumed.110 Breast cancer is the most common cancer
Complicating the recommendation for alco- diagnosed among American women and is sec-
hol and cancer risk reduction is the fact that low ond only to lung cancer as a cause of cancer
to moderate intake of alcoholic beverages has deaths in women.134 The risk of breast cancer is
been associated with decreased risk of coronary increased by several reproductive and other fac-
heart disease.102 Even though drinking moder- tors that are not easily modiﬁed: menarche before
ate levels of alcohol is associated with reduced age 12, nulliparity or first birth at age greater
risk of coronary heart disease in women, those than 30 years, late age at menopause, and a fam-
women who are at high risk of breast cancer ily history of breast cancer. Risk factors may dif-
might reasonably consider abstaining from alco- fer for breast cancer that is diagnosed before or
hol. There is no compelling reason for adults after menopause. New evidence indicates that
who currently do not consume alcoholic bever- exposures throughout life including in utero may
ages to start consuming alcohol to reduce their have an effect on breast cancer risk. That breast
risk for heart disease, as cardiovascular risk can cancer risk is increased with increasing adult
be reduced by other means, such as avoiding height strongly points to early-life nutritional
smoking, consuming a diet low in saturated and factors in breast cancer.
trans fats, maintaining a healthy weight, staying There is consistent evidence that increased
physically active on a regular basis, and control- body weight and weight gain during adulthood
ling blood pressure and lipids. Furthermore, are associated with increased risk for breast can-
there is convincing evidence that cardiovascu- cer among postmenopausal (but not premeno-
lar risk increases with heavy alcohol consump- pausal) women.34,37,112–117 This increased risk is
tion.102 Some groups of people should not drink likely due to the higher levels of estrogens pro-
alcoholic beverages at all. These include chil- duced by extra adipose tissue after menopause;
dren and adolescents; individuals of any age who the adverse effect of weight gain is not seen as
cannot restrict their drinking to moderate lev- readily among women taking postmenopausal
els or who have a family history of alcoholism; hormone therapy (hormone replacement ther-
women who are or may become pregnant; indi- apy), since it may be masked by higher levels
viduals who plan to drive or operate machinery of exogenous estrogens. Alcohol intake is also
or who take part in other activities that require associated with an increase in risk, 103,104,118
attention, skill, or coordination; and individuals particularly for women whose intake of folate
taking prescriptions or over-the-counter med- is low. 106–109 Moderate to vigorous physical
ications that can interact with alcohol. activity has been shown to be associated with
decreased breast cancer risk among both pre-
DIET AND PHYSICAL ACTIVITY FACTORS THAT
menopausal and postmenopausal women. 3
AFFECT RISKS FOR SELECT CANCERS Although reduction of fat intake to very low
levels may reduce breast cancer risk, results from
Bladder Cancer
the recent intervention trial found that lower-
The major risk factors for bladder cancer are to- ing fat intake to 29% of calories had only a very
bacco smoking and exposure to certain industrial small effect on risk among postmenopausal



women.119 At the present time, the best nutri- calcium; eat more vegetables and fruits; avoid
tional advice to reduce the risk of breast can- obesity; and avoid excess alcohol consumption
cer is to engage in moderate to vigorous physical (eg, no more than one drink/day in women,
activity 45 to 60 minutes on 5 or more days per two drinks/day in men).53,54,122,132 In addition,
week, minimize lifetime weight gain through it is very important to follow the ACS guide-
the combination of caloric restriction and reg- lines for regular colorectal screening, as identi-
ular physical activity, and avoid or limit intake fying and removing precursor polyps in the colon
of alcoholic beverages.6,104,115,120,121 can prevent colorectal cancer.133

Colorectal Cancer Endometrial Cancer

Colorectal cancer is the second leading cause Endometrial cancer is the most common female
of cancer death among American men and reproductive cancer in the United States, rank-
women combined.134 The risk of colorectal can- ing fourth among all cancers in women in age-
cer is increased in those with a family history of adjusted incidence.134 Although endometrial
colorectal cancer. Long-term tobacco use and cancer has been traditionally considered as a sin-
possibly excessive alcohol consumption increase gle entity, epidemiologic and clinicopathologic
risk, whereas use of aspirin or other nonsteroidal evidence points to two separate types. Type I
anti-inﬂammatory drugs, postmenopausal hor- endometrial cancer (low grade, the most common
mone therapy, and possibly increased calcium type) is hormonally related, associated with hyper-
intake may decrease risk. Currently, however, plasia, and tends to have a better prognosis.
neither aspirin-like drugs nor postmenopausal Type II endometrial cancer (high grade, approx-
hormones are recommended to prevent colorec- imately 10% of endometrial cancers) is not hor-
tal cancer because of their potential adverse monally related, is associated with endometrial
effects. Studies demonstrate a lower risk of colon atrophy, and tends to have a worse prognosis.135
cancer among those who are moderately active Most of the established risk factors for endome-
on a regular basis, and increasing evidence sug- trial cancer, summarized here, refer to type I; the
gests that more vigorous activity may have an causes of type II endometrial are largely unknown.
even greater beneﬁt in reducing the risk of colon Most of the major known risk factors for type
cancer.53,122 Obesity increases the risk of colon I endometrial cancer have in common a pro-
cancer among both men and women, but the longed and excessive exposure of the endo-
association seems to be stronger in men.3,27 Diets metrium to estrogens unopposed by progesterone,
high in vegetables and fruits have been associ- such as postmenopausal estrogen therapy, sequen-
ated with decreased risk, 11 and diets high in tial oral contraceptive formulations, a history of
processed and/or red meat have been associated polycystic ovarian syndrome, and obesity.
with increased risk of colon cancer.123–125 A There is strong evidence of a relationship
growing number of studies support a protective between obesity and endometrial cancer.3 In
role of calcium126,127 for colorectal cancer or its premenopausal women, the increased risk has
precursor, colorectal adenomas. Several studies been attributed to insulin resistance, elevation
also suggest that vitamin D128,129 or a combina- in ovarian androgens, anovulation, and chronic
tion of vitamin D and calcium130 may prevent progesterone deficiency associated with over-
this cancer. However, because of a potential weight. 135 In postmenopausal women, the
increase in risk of prostate cancer associated with increased risk has been attributed to the higher
calcium intake,131 it would be prudent to limit circulating concentration of bioavailable estro-
calcium intake in men to less than 1,500 mg/day gens created from the conversion of androstene-
until further studies are conducted. The best dione to estrone in adipose tissue. 3 Studies
nutritional advice to reduce the risk of colon examining physical activity, which has also been
cancer is to increase the intensity and duration shown to affect endogenous hormone levels,
of physical activity; limit intake of red and have suggested a decrease in endometrial can-
processed meat; consume recommended levels of cer risk for the highest level of physical activity.3



Vegetable and fiber intakes may decrease risk, lung cancer risk among smokers (see Beta Caro-
whereas red meat, saturated fat, and animal fat tene).76,77 At the present time, the best advice to
may increase risk.136 At the present time, the reduce the risk of lung cancer is to avoid tobacco
best advice to reduce the risk of endometrial use and environmental tobacco smoke and to
cancer is to maintain a healthy weight through avoid radon exposure. Eating at least five serv-
diet and regular physical activity, and eat a pre- ings of vegetables and fruits every day is also
dominantly plant-based diet rich in vegetables, advised.7,138
whole grains, and beans.

Ovarian Cancer
Kidney Cancer
Cancer of the ovary is the second most com-
In the United States, kidney cancer accounts mon gynecologic cancer and the leading cause
for 3% of both incident and fatal cancers in men of death from gynecologic malignancies. 134
and 2% of cancer cases and deaths in women.134 Although the etiology of ovarian cancer is not
The incidence of kidney cancer has been steadily well understood, hormonal, environmental, and
rising by nearly 2% annually since 1975. 137 genetic factors have been implicated. Family his-
Approximately 80% to 85% of kidney cancers tory of ovarian cancer is a risk factor, but fewer
are renal cell cancers. The etiology of renal cell than 10% of ovarian cancers are hereditary.
cancer is largely unknown; however, the most At the present time there are no established
established modifiable risk factors include obe- nutritional risk factors for ovarian cancer. In the
sity and tobacco smoking. In 2002, the Inter- Pooling Project of Diet and Cancer Cohorts, a
national Agency for Research on Cancer con- study combining the data from 12 cohort stud-
cluded that there is sufficient evidence for ies,139 there was no indication of an association
excessive weight as a cause of renal cell cancer.3 of risk with total fruit, total vegetable, total fruit
Results for associations between dietary factors and vegetable, or any botanically defined sub-
and renal cell cancer risk have been limited or group, and in the European Investigation into
inconsistent. At the present time, the best advice Cancer and Nutrition (EPIC) study,140 a very
to reduce the risk of kidney cancer is to main- large cohort study of women in Europe, total
tain a healthy weight and avoid tobacco use. fruit, total vegetables, or total fruit and vegeta-
bles were unrelated to ovarian cancer risk. The
Leukemias and Lymphomas
association with milk/dairy products and galac-
There are no known nutritional risk factors tose metabolism has been widely explored with
for leukemias or lymphomas at this time. inconsistent results.141,142 There was no indica-
tion of an association with milk/dairy product or
Lung Cancer calcium consumption in a recent study pooling
data from 12 cohort studies,143 whereas there was
Lung cancer is the leading cause of cancer some indication of a weak association with lactose
death among Americans.11,134 More than 85% intake at a level equivalent to three or more glasses
of lung cancers occur because of tobacco smok- of milk per day. The overall evidence seems to
ing, and 10% to 14% are attributed to radon indicate that alcohol consumption at moderate
exposure. Many studies have found that the risk levels may reduce the risk of ovarian cancer.110,144,145
of lung cancer is lower among smokers and non- The role of obesity and physical activity in ovar-
smokers who consume at least five servings of ian cancer risk is unclear.3,5,146
vegetables and fruits a day. A recent review found
significantly lower risk of lung cancer with higher Pancreatic Cancer
consumption of fruit.11 Although healthful eat-
ing may reduce the risk of lung cancer, the risks Pancreatic cancer is the fourth leading cause
posed by tobacco remain substantial. Nutritional of cancer death in the United States.134 Substantial
supplementation with high doses of beta carotene evidence indicates that tobacco smoking, adult-
and/or vitamin A has increased (not decreased) onset diabetes, and impaired glucose tolerance



increase the risk for pancreatic cancer.147 Some prostate cancer.131,152 Although obesity has been
studies have also shown that obesity and physi- inconsistently related to prostate cancer develop-
cal inactivity (both factors strongly linked to ment, recent data suggest that being overweight
abnormal glucose metabolism) and higher con- is associated with worse prognosis after diagno-
sumption of red and processed meat are associ- sis and treatment among men with prostate can-
ated with elevated pancreatic cancer risk, and cer. 31,153 Evidence suggests that exercise, in
that fruit and vegetable intake is associated with particular vigorous exercise, may impart some
reduced risk,148 but none of these relationships is benefit for prostate cancer.3 At the present time,

yet firmly established. At the present time, the the best advice to reduce the risk of prostate
best advice to reduce the risk of pancreatic can- cancer is to eat five or more servings of a wide
cer is to avoid tobacco use, maintain a healthful variety of vegetables and fruits each day, limit
weight, remain physically active, and eat five or intake of red meats and dairy products, and main-
more servings of vegetables and fruits each day. tain an active lifestyle and healthy weight.

Prostate Cancer Stomach Cancer

Prostate cancer is the most common cancer Stomach cancer is the fourth most common
among American men.134 Although prostate cancer worldwide and the number two cause of
cancer is related to male sex hormones, just how death from cancer.134 This cancer, however, is
nutritional factors might influence risk remains relatively uncommon in the United States. Many
uncertain.149 Several studies suggest that diets studies have found that high intake of fresh fruits
high in certain vegetables (including tomatoes/ and vegetables is associated with reduced risk of
tomato products, cruciferous vegetables, soy, stomach cancer, whereas high intake of salt-
beans, or other legumes) or fish are associated preserved foods is associated with increased
with decreased risk. There is some evidence that risk.154,155 There is also convincing evidence that
food or supplements containing specific antiox- chronic stomach infection by the bacterium
idant nutrients, such as vitamin E, selenium, Helicobacter pylori increases the risk of stomach
beta carotene, and lycopene, may reduce prostate cancer.154,155 Although the overall incidence of
cancer risk. Whether vitamin E and/or selenium stomach cancer continues to decrease in most
reduce prostate cancer incidence is currently parts of the world, the incidence of this cancer
being tested in a large clinical trial. Most epi- in the gastric cardia has increased recently in the
demiologic studies have not consistently distin- United States and several European countries.156
guished between specific nutrients and the foods The reasons for the increase are under active
in which they occur. The biological plausibil- investigation but may be tied to increases in lower
ity that certain nutrients may affect prostate can- esophageal cancers caused by gastric reflux from
cer risk has been strengthened by recent reports abdominal obesity.156 At the present time, the
of gene-diet interactions for these nutrients and best advice for reducing the risk of stomach can-
specific genes involved in antioxidant function cer is to eat at least five servings of vegetables
and DNA repair.149 Some of the genotypes were and fruits daily, reduce salt-preserved food con-
fairly common in the predominantly Caucasian sumption, and maintain a healthy weight.
populations studied (eg, 25%), and men with
the specific genotype who had higher versus Upper Aerodigestive Tract Cancers
lower levels of these circulating nutrients were
greatly protected against prostate cancer.150 Several In the United States, upper digestive tract
studies have observed that greater consumption cancers are significantly more common among
of red meat or dairy products may be associated men than women. Tobacco (including cigarettes,
with increased risk of prostate cancer.97,98,151 chewing tobacco, and snuff ) and alcohol, alone,
There is also evidence that a high calcium intake, but especially when used together, increase the
primarily through supplements, is associated risk for cancers of the mouth, larynx, pharynx,
with increased risk for more aggressive types of and esophagus; these exposures contribute



substantially to the gender disparities for these distilled spirits. The combination of alcohol and
cancers. Obesity increases the incidence of ade- tobacco increases the risk of some cancers far
nocarcinoma in the lower esophagus and at the more than the independent effects of either
junction of the esophagus and stomach, likely as drinking or smoking.5 Regular consumption of
a result of epithelial damage, metaplasia, and dys- even a few drinks per week is associated with
plasia associated with acid reflux. There is some an increased risk of breast cancer in women—a
evidence to suggest that consuming beverages risk that is particularly high in women who do
and foods that are very hot in temperature may not get enough folate.103,104,109 Women at high

increase risk for oral and esophageal cancers, risk of breast cancer may consider abstaining
likely as a result of thermal damage to exposed tis- from alcohol.
sue. Eating recommended amounts of vegeta-
bles and fruits probably reduces the risk of oral and Antioxidants
esophageal cancers. At the present time, the best
advice to reduce the risk of cancers of the upper What are antioxidants, and what do they have to
digestive and respiratory tracts is to avoid all forms do with cancer? Along with a number of other
of tobacco, restrict alcohol consumption, avoid defense systems, the body appears to use certain
obesity, and eat at least five servings of a variety nutrients in vegetables and fruits to protect the
of vegetables and fruits each day.157–159 body against damage to tissues that occurs con-
stantly as a result of normal metabolism (oxida-
tion). Because such damage is associated with
COMMON QUESTIONS ABOUT DIET, PHYSICAL increased cancer risk, the so-called antioxidant
ACTIVITY, AND CANCER nutrients are thought to protect against cancer.160
Antioxidants include vitamin C, vitamin E,
Because people are interested in the relation- carotenoids, and many other phytochemicals.
ship that specific foods, nutrients, or lifestyle Studies suggest that people who eat more veg-
factors have to specific cancers, research on health etables and fruits, which are rich sources of
behaviors and cancer risk is often widely publi- antioxidants, may have a lower risk for some
cized. Health professionals who counsel patients types of cancer.11 Clinical studies of antioxidant
should emphasize that no one study provides supplements are currently under way, but stud-
the last word on any subject, and that individual ies have not yet demonstrated a reduction in
news reports may overemphasize what appear cancer risk from vitamin or mineral supple-
to be contradictory or conflicting results. In brief ments73 (see also Beta Carotene, Lycopene, Vitamin
news stories, reporters cannot always put new E, Supplements). To reduce cancer risk, the best
research findings in their proper context. The advice presently is to consume antioxidants
best advice about diet and physical activity is through food sources rather than supplements.
that it is rarely, if ever, advisable to change diet
or activity levels based on a single study or news Aspartame
report. The following questions and answers
address common concerns about diet and phys- Does aspartame cause cancer? No. Aspartame is
ical activity in relation to cancer. a low-calorie artificial sweetener that is about
200 times sweeter than sugar. Current evidence
Alcohol does not demonstrate any link between aspar-
tame ingestion and increased cancer risk.161,162
Does alcohol increase cancer risk? Yes. Alcohol People with the genetic disorder phenylketonuria
increases the risk of cancers of the mouth, phar- should avoid aspartame in their diets.
ynx, larynx, esophagus, liver, colorectum, and
breast.5,101 People who drink alcohol should Beta Carotene
limit their intake to no more than two drinks
per day for men and one drink per day for Does beta carotene reduce cancer risk? Because
women.15 A drink is defined as 12 ounces of beer, beta carotene, an antioxidant chemically related
5 ounces of wine, or 1.5 ounces of 80-proof to vitamin A, is found in vegetables and fruits,


American Cancer Society Guidelines for Nutrition Management

American Cancer Society Guidelines for Nutrition Management

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