AHA Scientific Statement |
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Abstract |
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Key Words: AHA Scientific Statements • nutrition •
cardiovascular diseases
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Introduction |
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Consistent with the strategic plan of the AHA, the 2006 AHA Diet and Lifestyle Recommendations are one component of a comprehensive plan to achieve specific goals for cardiovascular risk reduction (Table 1). The recommendations (Table 2) are appropriate for the general public, including adults and children over 2 years of age. Separate AHA dietary guidelines specifically addressing the special needs of growing children have recently been published.3 The AHA 2006 Diet and Lifestyle Recommendations are intentionally flexible to meet the unique needs for growth, development, and aging.
TABLE 1. AHA 2006 Diet and Lifestyle Goals for Cardiovascular Disease Risk Reduction
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Evidence cited in this report is drawn from many authoritative documents, including previous AHA scientific statements and other evidence-based reviews, as well as seminal studies and national surveys.
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Public Health and Clinical Application of AHA Diet and Lifestyle Recommendations |
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Clinical Recommendations
The general recommendations contained in this document generally can
be applied to the clinical management of patients with or at risk for
CVD. For certain patients at higher risk, the recommendations may
have to be intensified. Although great advances have been made in
prevention and treatment of CVD through drug therapies and
procedures, diet and lifestyle therapies remain the foundation of
clinical intervention for prevention. Unfortunately, the latter
commonly are neglected, to the detriment of patients. Rigorous
application of the principles of diet and lifestyle intervention
outlined in this document to patients at risk will contribute
significantly to risk reduction and will augment the benefit that may
be obtained by other approaches. The clinical approach is an
extension of the public health approach, with some modifications
depending on the type of patient.
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Goals |
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Consume an Overall Healthy Diet
Although the vast majority of research studies have focused on
individual nutrients and foods, it is well recognized that multiple
dietary factors influence the risk of developing CVD and its major
risk factors. To a much lesser extent, research has examined the
health effects of the whole diet; both observational studies and
clinical trials. These data have documented that healthy dietary
patterns are associated with a substantially reduced risk of CVD,4
CVD risk factors,5,6 and noncardiovascular
diseases.7 An emphasis on whole diet
is also appropriate to ensure nutrient adequacy and energy balance.2
Hence, rather than focusing on a single nutrient or food, individuals
should aim to improve their whole or overall diet. Consistent with
this principle, the AHA recommends that individuals consume a
variety of fruits, vegetables, and grain products, especially whole
grains; choose fat-free and low-fat dairy products, legumes, poultry,
and lean meats; and eat fish, preferably oily fish, at least twice a
week (Table 2).
Aim for a Healthy Body Weight
A healthy body weight is currently defined as a body mass index (BMI)
of 18.5 to 24.9 kg/m2. Overweight is a BMI between 25 and
29.9 kg/m2, and obesity is a BMI 
30
kg/m2. In the United States, achieving and maintaining a
healthy weight throughout life is particularly difficult. Currently,
about one third of adults are overweight, and an additional one third
are obese.8,9 The prevalence of
overweight and obesity has increased dramatically over the past 20
years, and the problem has now reached epidemic proportions.9,10
Of particular concern is that this trend has shown no signs of
abating. Obesity is an independent risk factor for CVD.11
Excess body weight adversely affects CVD risk factors (eg, increasing
low-density lipoprotein [LDL] cholesterol levels, triglyceride
levels, blood pressure [BP], and blood glucose levels, and reducing
high-density lipoprotein [HDL] cholesterol levels) and increases the
risk of developing coronary heart disease (CHD), heart failure,
stroke, and cardiac arrhythmias.
The causes of this dramatic population-wide increase in overweight and obesity are multifactorial. Implicated factors include increased portion sizes; high–calorie-density foods; easy access to plentiful, inexpensive food; sedentary lifestyle; and commercial and cultural influences that, in aggregate, encourage calorie consumption in excess of calorie utilization. No one factor appears responsible for the epidemic. Hence, the optimal strategy to retard the epidemic must likewise be multifactorial.
Achieving and maintaining a healthy weight throughout the life cycle are critical factors in reducing CVD risk in the general population. Data indicate that body weight at 18 years tracks with subsequent risk of developing CVD and diabetes, as does weight gain after 18 years of age.12 It is important to intensify efforts in the general population to help individuals avoid inappropriate weight gain during childhood and subsequent weight gain during adult years. Increased emphasis should be put on prevention of weight gain, because achievement and maintenance of weight loss, although certainly possible, require more difficult behavioral changes (ie, greater calorie reduction and more physical activity) than prevention of weight gain in the first place.13,14
Aim for a Desirable Lipid Profile
LDL, which is the major cholesterol-carrying lipoprotein particle in
plasma, is primarily derived from lipoprotein particles made by the
liver. As levels of LDL cholesterol increase, so does the risk of
developing CVD.15 LDL levels are classified
as follows: optimal, <100 mg/dL; near or above optimal, 100 to 129
mg/dL; borderline high, 130 to 159 mg/dL; high, 160 to 189 mg/dL; and
very high, 190 mg/dL.15
Among non-Hispanic whites living in the United States, 17% of women
and 20% of men have LDL cholesterol levels >160 mg/dL.9
Corresponding estimates for non-Hispanic blacks are 19% of women and
19% of men, and for Mexican Americans, 14% of women and 17% of men.9
Current recommendations for LDL cholesterol goals depend on the estimated 10-year risk of developing CVD and the presence of CVD-related risk factors.15 Although drug therapy is often prescribed for those at moderate or high risk, dietary changes are recommended for all individuals. The strongest dietary determinants of elevated LDL cholesterol concentrations are dietary saturated fatty acid and trans fatty acid intakes. Trans fatty acids tend to increase LDL cholesterol levels slightly less than saturated fatty acids, whereas saturated fatty acids increase HDL cholesterol concentrations but trans fatty acids do not.16 To a lesser extent, dietary cholesterol and excess body weight are positively related to levels of LDL cholesterol.15
HDL cholesterol and triglycerides are other plasma lipid measures related to CVD risk that can be affected by diet and body weight.17,18 The concentration of HDL cholesterol is inversely associated with the risk of developing CVD.15 This association is thought to be mediated by a constellation of events collectively referred to as reverse cholesterol transport—the transport of cholesterol from peripheral tissues to the liver for subsequent metabolism or excretion. HDL directly protects against the development of atherosclerosis. The major nongenetic determinants of low HDL cholesterol levels are hyperglycemia, diabetes, hypertriglyceridemia, very low-fat diets (<15% energy as fat), and excess body weight.17 Although at this time there are no HDL cholesterol goals as there are for LDL cholesterol, levels <50 mg/dL in women and <40 mg/dL in men are considered one of the criteria for the classification of metabolic syndrome.15 Likewise, although at this time there are no triglyceride goals, levels >150 mg/dL are considered one of the criteria for the classification of metabolic syndrome.15 In general, a moderate inverse relationship exists between triglyceride and HDL cholesterol concentrations, and determinants of high triglycerides are mainly the same as those of low HDL cholesterol.17
Aim for a Normal Blood Pressure
A normal BP is a systolic BP <120 mm Hg and a diastolic BP <80 mm Hg.
BP is a strong, consistent, continuous, independent, and
etiologically relevant risk factor for cardiovascular-renal disease.
Notably, no evidence of a BP threshold exists—that is, the risk of
CVD increases progressively throughout the range of BP, including the
prehypertensive range (a systolic BP of 120 to 139 mm Hg or diastolic
BP of 80 to 89 mm Hg).19 Hence,
efforts to reduce BP to normal levels are warranted, even among
individuals with prehypertension.
According to the most recent National Health and Nutrition Examination
Survey (NHANES) (1999–2000), 27% of adult Americans have
hypertension (systolic BP 140 mm Hg,
diastolic BP 90 mm Hg, or use of
antihypertensive medication), and another 31% have prehypertension.20
It has been estimated that among adults >50 years of age, the
lifetime risk of developing hypertension approaches 90%. On average,
blacks have higher BP than do nonblacks, as well as an increased risk
of BP-related complications.
Elevated BP results from environmental factors, genetic factors, and interactions among these factors. Of the environmental factors that affect BP (ie, diet, physical inactivity, toxins, and psychosocial factors), dietary factors have a prominent, and likely predominant, role. A substantial body of evidence strongly supports the concept that multiple dietary factors affect BP.21 Dietary modifications that lower BP are reduced salt intake, caloric deficit to induce weight loss, moderation of alcohol consumption (among those who drink), increased potassium intake, and consumption of an overall healthy diet, based on the DASH (Dietary Approaches to Stop Hypertension) diet.5 The latter is a carbohydrate-rich diet that emphasizes fruits, vegetables, and low-fat dairy products; includes whole grains, poultry, fish, and nuts; and is reduced in fats, red meat, sweets, and sugar-containing beverages. Replacement of some carbohydrates with either protein from plant sources or with monounsaturated fat can further lower BP.6
Aim for a Normal Blood Glucose Level
A normal fasting glucose level is 
100
mg/dL, whereas diabetes is defined by a fasting glucose level
126 mg/dL. Hyperglycemia and the
often-associated insulin resistance are related to numerous
cardiovascular complications, including CHD, stroke, peripheral
vascular disease, cardiomyopathy, and heart failure. Type 2 diabetes
is the most common form of diabetes. Reducing caloric intake and
increasing physical activity to achieve even a modest weight loss can
decrease insulin resistance and improve glucose control and the
concomitant metabolic abnormalities. In nondiabetic individuals,
weight loss and increased physical activity can delay the onset of
and possibly prevent diabetes.22,23
Be Physically Active
Regular physical activity is essential for maintaining physical and
cardiovascular fitness, maintaining healthy weight, and sustaining
weight loss once achieved.24 Current
estimates indicate that 61% of US adults do not engage in any regular
physical activity.9 A sedentary
lifestyle is associated with older age and is more common among
Hispanic or Latino and black adults than among white adults. Regular
physical activity improves cardiovascular risk factors (BP, lipid
profiles, and blood sugar) and lowers the risk of developing other
chronic diseases, including type 2 diabetes, osteoporosis, obesity,
depression, and cancer of the breast and colon.25
Avoid Use of and Exposure to Tobacco Products
On the basis of the overwhelming evidence for the adverse effects of
tobacco products and secondary exposure to tobacco smoke on CVD, as
well as cancer and other serious illness, the AHA strongly and
unequivocally endorses efforts to eliminate the use of tobacco
products and minimize exposure to second-hand smoke.26–28
Nearly 23% of US adults smoke, with the highest rates in American
Indian/Alaskan Native women (37%) and the lowest rates in Asian women
(7%).9 Because cessation of smoking
in habitual smokers can be associated with weight gain, particular
attention should be given to preventing this outcome.29
Concern about weight gain should not be a reason for continued use of
tobacco products.
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AHA Diet and Lifestyle Recommendations |
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TABLE 3. Practical Tips to Implement AHA 2006 Diet and Lifestyle Recommendations
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TABLE 4. Two Examples of Daily Dietary Patterns That Are Consistent With AHA-Recommended Dietary Goals at 2000 Calories
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Although the recommendations present guidance about specific nutrients and types of foods, the importance of an overall healthy diet and lifestyle cannot be overemphasized. Multiple dietary factors influence CVD risk, and not all do so via changes in the risk factors described above. Hence, CVD benefit is likely to accrue by adherence to a healthy diet and lifestyle even if these risk factors are not markedly altered. Although the Food and Drug Administration (FDA) has sanctioned health claims for certain nutrients and foods, a focus on the overall diet is preferred over a specific focus on individual dietary components. This is, in part, due to the overarching goal of achieving energy balance and nutrient adequacy. If a specific food or category of foods is added to, rather than used to displace, other food from the diet (eg, as a result of an FDA claim or new research finding), then the additional calories can lead to weight gain.
Balance Calorie Intake and Physical Activity to Achieve or Maintain a
Healthy Body Weight
To avoid weight gain after childhood, individuals must control
calorie intake so that energy balance is achieved—that is, energy
intake matches energy expenditure. To control calorie intake,
individuals should increase their awareness of the calorie content of
foods and beverages per portion consumed and should control portion
size.30 The macronutrient composition of a
diet (ie, the amount of fat, carbohydrate, and protein) has little
effect on energy balance unless macronutrient manipulation influences
total energy intake or expenditure.30
While reducing caloric intake, individuals should adopt and maintain
a diet consistent with recommendations in this document (Table
2).
A physically active lifestyle is recommended to reduce risk for CVD in all individuals, regardless of body weight.13 Regular physical activity also reduces symptoms in patients with established CVD. Among individuals who are overweight or obese, regular physical activity along with calorie restriction is recommended as a means to achieve weight loss. Regular daily physical activity has been shown to be particularly effective in maintaining weight loss once achieved.14
The AHA recommends that all adults accumulate
30 minutes of physical activity
most days of the week. Additional benefits will likely be derived if
activity levels exceed this minimum recommendation. At least 60
minutes of physical activity most days of the week is recommended for
adults who are attempting to lose weight or maintain weight loss and
for children. The physical activity can be accumulated throughout the
day. It is not easy for individuals to achieve these goals. However,
it is important to encourage behaviors that will facilitate
achieving and maintaining these goals over time. Achieving a
physically active lifestyle requires effective time management, with
a particular focus on reducing sedentary activities such as screen
time (eg, watching television, surfing the Web, playing computer
games) and making daily choices to move rather than be moved (eg,
taking the stairs instead of the elevator).
Consume a Diet Rich in Vegetables and Fruits
Most vegetables and fruits are rich in nutrients, low in calories,
and high in fiber. Therefore, diets high in vegetables and fruits
meet micronutrient, macronutrient, and fiber requirements without
adding substantially to overall energy consumption. Whether it is the
vegetables and fruits themselves or the absence of other foods
displaced from the diet that is associated with CVD risk reduction
has yet to be determined. Regardless, diets rich in vegetables and
fruits have been shown to lower BP and improve other CVD risk factors
in short-term randomized trials.5,6,31
In longitudinal observation studies, persons who regularly consume
such diets are at a lower risk of developing CVD, particularly
stroke.32,33
A variety of vegetables and fruits are recommended. Vegetables and fruits that are deeply colored throughout (eg, spinach, carrots, peaches, berries) should be emphasized because they tend to be higher in micronutrient content than are other vegetables and fruits such as potatoes and corn. Fruit juice is not equivalent to the whole fruit in fiber content and perhaps satiety value and should not be emphasized. A diet rich in vegetables and fruits is a strategy for lowering the energy density of the diet to control energy intake. Equally important is the method of preparation. Techniques that preserve nutrient and fiber content without adding unnecessary calories, saturated or trans fat, sugar, and salt are recommended (Table 3).
Choose Whole-Grain, High-Fiber Foods
Dietary patterns that are high in whole-grain products and fiber have
been associated with increased diet quality and decreased risk of
CVD.34 Soluble or viscous fibers (notably
ß-glucan and pectin) modestly reduce LDL cholesterol levels beyond
those achieved by a diet low in saturated and trans fatty
acids and cholesterol alone.35
Insoluble fiber has been associated with decreased CVD risk36–38
and slower progression of CVD in high-risk individuals.39
Dietary fiber may promote satiety by slowing gastric emptying,
leading to an overall decrease in calorie intake.40,41
Soluble fiber may increase short-chain fatty acid synthesis, thereby
reducing endogenous cholesterol production.41
The AHA recommends that at least half of grain intake come from whole
grains.
Consume Fish, Especially Oily Fish, at Least Twice a Week
Fish, especially oily fish, is rich in very long-chain omega-3
polyunsaturated fatty acids: eicosapentaenoic acid, C20:5n-3 (EPA)
and docosahexaenoic acid, C22:6n-3 (DHA). The consumption of 2
servings (&8 ounces) per week of fish high in EPA and DHA is
associated with a reduced risk of both sudden death and death from
coronary artery disease in adults.42,43 In
addition to providing EPA and DHA, regular fish consumption may
facilitate the displacement of other foods higher in saturated and
trans fatty acids from the diet, such as fatty meats and full-fat
dairy products. Methods used to prepare fish should minimize
the addition of saturated and trans fatty acids, as occurs with
the use of cream sauces or hydrogenated fat during frying.
Contamination of certain fish with methyl mercury, polychlorinated biphenyls, and other organic compounds is a potential concern.44 Subgroups of the population, primarily children and pregnant women, are advised by the FDA to avoid eating those fish with the potential for the highest level of mercury contamination (eg, shark, swordfish, king mackerel, or tilefish), eat up to 12 ounces (2 average meals) per week of a variety of fish and shellfish that are lower in mercury (eg, canned light tuna, salmon, pollock, catfish), and check local advisories about the safety of fish caught by family and friends in local lakes, rivers, and coastal areas.45 Potential exposure to some contaminants can be reduced by removing the skin and surface fat from these fish before cooking. For middle-aged and older men and postmenopausal women, the benefits of fish consumption far outweigh the potential risks when amounts of fish are eaten within the recommendations established by the FDA and Environmental Protection Agency. Consumers should also check with local and state authorities about types of fish and watersheds that may be contaminated and the FDA Web site for the most up-to-date information on recommendations for specific subgroups of the US populations (eg, children, pregnant women).
Limit Your Intake of Saturated and Trans Fat and Cholesterol
As a set of goals, the AHA recommends intakes of <7% of energy as
saturated fat, <1% of energy as trans fat, and <300 mg
cholesterol per day. These goals can be achieved by (1) choosing lean
meats and vegetable alternatives; (2) selecting fat-free (skim),
1%-fat, and low-fat dairy products; and (3) minimizing intake of
partially hydrogenated fats.
Diets low in saturated and trans fatty acids and cholesterol reduce the risk of CVD, in large part through their effects on LDL cholesterol levels. For all age groups of the US population, in 1999 to 2000, the daily mean percentage of calories from saturated fats was 11.2.46 In those same years, average cholesterol intakes for men and women ages 20 to 74 years were 341 mg and 242 mg, respectively.46 The mean trans fatty acid intake has been estimated to be &2.7% of energy.47 This number should only be considered a crude estimate because it is likely current intakes are shifting, in part prompted by the new trans fatty acid labeling requirement. Subgroups within the population are likely to have higher or lower intakes based on their habitual dietary practices.
In the current US diet, the major sources of saturated fatty acids are animal fats (meat and dairy), and the primary sources of trans fatty acids are partially hydrogenated fats used to prepare commercially fried and baked products. Major sources of dietary cholesterol are foods of animal origin (eggs, dairy, and meat). Saturated and trans fatty acid intakes are directly related to LDL cholesterol levels.48–50 Increased dietary cholesterol intake also raises LDL cholesterol concentrations.
Efforts to reduce saturated fat and cholesterol typically rely on replacement of animal fats with unsaturated fats (polyunsaturated and monounsaturated fats) and on selection of lower-fat versions of foods (eg, replacing full-fat dairy products with nonfat or low-fat versions). Replacing meats with vegetable alternatives (eg, beans) or fish is one strategy to replace saturated fats with unsaturated fats and reduce the cholesterol content. In view of the positive linear relationship among dietary saturated fat, LDL cholesterol, and CVD risk, and current US intakes, the AHA now recommends a population-wide goal of <7% of energy. Efforts to reduce trans fatty acids typically rely on the substitution of partially hydrogenated fats with those made with liquid vegetable oils (with the exception of tropical fats). With the introduction of mandatory trans fat labeling on January 1, 2006, it is easier for consumers to identify and limit their trans fatty acid intake. However, even if partially hydrogenated fats were removed from the food supply, it is estimated that trans fats still would represent &1% of the calories because some trans fatty acids are produced from deodorization of vegetable oils and because meat and dairy products contain naturally occurring trans fatty acids.50
There are currently no numerical goals for trans fat. The Institute
of Medicine recommends limiting trans fat intake as much as
possible,48 and both the 2005 Dietary
Guidelines Advisory Committee and a recent FDA Food Advisory
Committee, Nutrition Subcommittee, recommended that the intake of
trans fat be 1% of energy.50,51
(The FDA subcommittee voted [6 yes, 1 abstaining] in favor of
the recommendation.) For this reason, the AHA recommends the goal of
a diet containing <1% trans fatty acids.
The relative health effects of polyunsaturated and monounsaturated fats are actively debated. A few clinical outcome trials have documented that replacement of saturated fat with polyunsaturated fats reduces the risk of developing CHD, whereas prospective observational studies have documented that diets rich in monounsaturated fats are associated with a reduced risk of CHD. The AHA supports the recommendations of the Institute of Medicine and the National Cholesterol Education Program for total fat. A range of 25% to 35% for total fat is an appropriate level of intake in a healthy dietary pattern.
Minimize Your Intake of Beverages and Foods With Added Sugars
Over the past few decades, the consumption of beverages and foods
with added sugars has risen markedly. The intake of added sugars
(sucrose, corn syrup, and high-fructose corn syrup) increased from
13.1% of energy during the period 1977 to 1978 to 16.6% of energy
during 1999 to 2002.52,53
The primary reasons for reducing the intake of beverages and foods with added sugars are to lower total calorie intake and promote nutrient adequacy.54 Individuals who consume large amounts of beverages with added sugars tend to consume more calories and gain weight.55–57 Some evidence suggests that calories consumed as liquid are not as satiating as calories consumed as solid food.58 This factor may negatively affect attempts to achieve and maintain a healthy body weight.
Choose and Prepare Foods With Little or No Salt
On average, as salt (sodium chloride) intake increases, so does BP.59,60
A reduced sodium intake can prevent hypertension in nonhypertensive
individuals, can lower BP in the setting of antihypertensive
medication, and can facilitate hypertension control. A reduced sodium
intake is associated with a blunted age-related rise in systolic BP
and a reduced risk of atherosclerotic cardiovascular events and
congestive heart failure. In general, the effects of sodium reduction
on BP tend to be greater in blacks; middle-aged and older-aged
persons; and individuals with hypertension, diabetes, or chronic
kidney disease (CKD). Diets rich in potassium lower BP and also blunt
the BP-raising effects of an increased sodium intake.59
Because of the progressive dose-response relationship between sodium intake and BP, it is difficult to set a recommended upper level of sodium intake, which could be as low as 1.5 g/d (65 mmol/d). However, in view of the available high-sodium food supply and the currently high levels of sodium consumption, a reduction in sodium intake to 1.5 g/d (65 mmol/d) is not easily achievable at present. In the interim, an achievable recommendation is 2.3 g/d (100 mmol/d).
If You Consume Alcohol, Do So in Moderation
Moderate alcohol intake has been associated with reduced cardiovascular
events in many populations.2 This
association is not only found with wine but also with other alcoholic
beverages.61,62 Unlike other
potentially beneficial dietary components, the consumption of alcohol
cannot be recommended solely for CVD risk reduction. Alcohol can be
addictive, and high intake can be associated with serious adverse
health and social consequences, including hypertriglyceridemia,
hypertension, liver damage, physical abuse, vehicular and work
accidents, and increased risk of breast cancer.2
For these reasons, and on the basis of available epidemiological
data, the AHA recommends that if alcoholic beverages are consumed,
they should be limited to no more than 2 drinks per day for men and 1
drink per day for women, and ideally should be consumed with meals.63
In general, a 12-ounce bottle of beer, a 4-ounce glass of wine, and a
1
-ounce shot of 80-proof spirits all
contain the same amount of alcohol (one half ounce). Each of these is
considered a "drink equivalent."63,64
Individuals who choose to consume alcoholic beverages should also be aware that alcohol has a higher caloric density than protein and carbohydrate and is a source of additional "empty" calories.
When You Eat Food That Is Prepared Outside of the Home, Follow the
AHA 2006 Diet and Lifestyle Recommendations
Increasingly, Americans consume food that is prepared outside of the
home. Such types of "away" food include food prepared at restaurants
and grocery stores, quick-serve establishments, schools and daycare
centers, and other non-home locations. Between 1977 to 1978 and 1994
to 1996, consumption of away food increased from 18% to 32% of
calories.65 Large portion sizes and high
energy density are common features of away food.66
Many types of away foods, particularly traditional quick-serve, are
also high in saturated fat, trans fatty acids, cholesterol,
added sugars, and sodium and low in fiber and micronutrients. Adverse
health consequences have emerged. There is a positive association
between frequency of meal consumption at quick-serve restaurants
and total energy intake, weight gain, and insulin resistance.67
Attainment of a healthy diet will require individuals to make
wise choices when they eat food prepared outside of the home.
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Dietary Factors With Unproven or Uncertain Effects on CVD Risk |
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Soy Protein
Evidence of a direct cardiovascular health benefit from consuming soy
protein products instead of dairy or other proteins or of isoflavone
supplements is minimal.71,72 Although
earlier research has suggested that soy protein has clinically
important favorable effects on LDL cholesterol levels and other CVD
risk factors, studies reported during the past 5 years have not
confirmed those results.72 A
very large amount of soy protein, comprising more than half of daily
protein intake, may lower LDL cholesterol levels by a few percentage
points when it replaces dairy protein or a mixture of animal
proteins, but data are mainly from hypercholesterolemic individuals.
The evidence favors soy protein rather than soy isoflavones as the
responsible nutrient.76 No meaningful
benefit of soy consumption is evident with regard to HDL cholesterol,
triglycerides, or lipoprotein(a). Nevertheless, consumption of
soy protein–rich foods may indirectly reduce CVD risk if they replace
animal and dairy products that contain saturated fat and cholesterol.
Folate and Other B Vitamins
Available evidence is inadequate to recommend folate and other B
vitamin supplements as a means to reduce CVD risk at this time.
Folate intake and to a lesser extent intake of vitamins B6 and B12
are inversely associated with blood homocysteine levels. In
observational studies, increased blood levels of homocysteine are
associated with an increased risk of CVD.77
Trials of homocysteine-reducing vitamin therapy have been disappointing,
however.78–82
Phytochemicals
Flavonoids and sulfur-containing compounds are classes of compounds
found in fruits and vegetables that may be important in reducing the
risk of atherosclerosis. Within these categories are multiple
possible compounds, most of which are not well characterized and
whose modes of action are not established.83
Until more of this information is gathered and fully understood, a
diet consistent with AHA recommendations (Table 2)
is the most prudent way to ensure optimum consumption of
macronutrients, micronutrients, and associated bioactive compounds.32
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Other Dietary Factors That Affect CVD Risk |
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Plant Stanols/Sterols
Plant stanols/sterols lower LDL cholesterol levels by up to 15%85
and therefore are seen as a therapeutic option, in addition to diet
and lifestyle modification, for individuals with elevated LDL
cholesterol levels. Maximum effects are observed at plant stanol/sterol
intakes of &2 g per day. Plant stanol/sterols are currently available
in a wide variety of foods, drinks, and soft gel capsules. The choice
of vehicle should be determined by availability and by other
considerations, including caloric content. To sustain LDL cholesterol
reductions from these products, individuals need to consume them
daily, just as they would use lipid-lowering medication.
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Special Groups |
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Older Adults
Atherosclerosis is a chronic process beginning in youth. The risk of
developing CVD increases dramatically with advancing age. Diet and
lifestyle behaviors can decrease CVD risk.86
Also, ample evidence from clinical trials indicates that older-aged
persons can make and sustain lifestyle changes, perhaps more so
than younger adults.86,87 Because of the
high incidence of CVD events in older-aged individuals, even
relatively small improvements in risk factors (eg, small reductions
in BP and LDL cholesterol through diet and lifestyle changes) should
be of substantial benefit.88,89
In general, the goals and recommendations described in this document
are appropriate for older-aged individuals. Because they have
decreased energy needs while their vitamin and mineral requirements
remain constant or increase, however, older individuals should be
counseled to select nutrient-dense choices within each food group.90
Persons With Metabolic Syndrome
Metabolic syndrome refers to a cluster of abnormalities that are
related to insulin resistance and that commonly occur in the setting
of overweight and obesity.91 Characteristic
features of the metabolic syndrome are abdominal obesity, atherogenic
dyslipidemia (elevated triglycerides, low HDL cholesterol),
increased BP, insulin resistance (with or without glucose intolerance),
and prothrombotic and proinflammatory states.17,91
The primary approach to reducing CVD risk in persons with the
metabolic syndrome is to control the individual risk factors by diet
and lifestyle intervention.85
Physical activity and weight maintenance are recommended as a means
to prevent the development of metabolic syndrome and lower the risk
of developing type 2 diabetes or CHD.91
Very low-fat diets should be avoided if elevated triglyceride or
depressed HDL cholesterol levels are present.92
Reducing caloric intake while maintaining a moderate-fat diet and
increasing physical activity to achieve even a modest weight loss can
improve insulin resistance and the concomitant metabolic
abnormalities.
Persons With Chronic Kidney Disease
CKD, which precedes end-stage kidney disease, substantially increases
the risk of CVD, at least in part through diet-related CVD risk
factors.93 CKD is associated with a high
prevalence of diabetes, dyslipidemia (especially
hypertriglyceridemia), and hypertension. Dietary therapies
recommended for the general population are also recommended for
persons with early stages of CKD, even though empiric evidence is
sparse. In particular, a reduced salt intake is recommended as a
means to reduce BP and prevent fluid overload, and dietary strategies
to manage dyslipidemia are also recommended. Replacing meat with
dairy and vegetable alternatives may also slow loss of kidney
function.94 At advanced stages
of CKD, the dietary management of CKD diverges from general
population recommendations; in particular, a reduced intake of
protein, phosphorus, and potassium is recommended.
Socioeconomic Groups at High Risk of CVD
It is well recognized that individuals of lower socioeconomic status
have a higher incidence of CVD than do individuals of higher
socioeconomic status. Population subgroups of racial/ethnic
minorities (eg, Mexican Americans, American Indians, and blacks), who
are overrepresented in lower socioeconomic status groups, have a
strikingly high prevalence of overweight and obesity—a condition that
precedes the development of many other CVD risk factors.95,96
Although the reasons for such disparities are complex and
multifactorial, available research is sufficient to advocate diet and
lifestyle changes as a means to reduce disparities. For example,
blacks are especially sensitive to the BP-lowering effects of a
reduced salt intake, increased potassium intake, and the DASH diet.6
Promotion of a desirable diet should be culturally sensitive and should encourage healthy preparation of traditional ethnic foods. Unfortunately, social and economic barriers make widespread adoption of current diet and lifestyle recommendations difficult for many segments of society. Targeted diet and lifestyle messages directed at ethnic minorities and policies that affect availability and affordability are critically needed to reduce CVD health disparities.
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Environmental Influences on CVD Health Behaviors |
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The obesity epidemic, which has unfolded over the past 2 decades in genetically stable populations, illustrates the adverse impact of environment on diet and lifestyle behaviors. In brief, it is well recognized that the current environment encourages overconsumption of calories and discourages expenditure of energy. There is a growing agreement among experts that changes in the environment are a major driving force behind the obesity epidemic.97 Environmental factors that contribute to excess calorie intake are increased portion sizes, high-calorie foods, and easy access to plentiful inexpensive food. Environmental factors that discourage physical activity include an environment that encourages automobile use rather than walking and that has few cues to promote activity and numerous cues that discourage activity (eg, poor pedestrian infrastructure, lack of sidewalks and other safety features, and poor street aesthetics). Other factors include reduced energy expenditures at school, work, and home, and increased time spent on sedentary activities such as watching television, using computers, and playing video games.
The effects of environmental factors and of individual nutrients and food groups on overweight and obesity (eg, role of fat, added sugars, alcohol, fruits and vegetables, dairy products, physical inactivity) have been explored. No one factor appears responsible for the epidemic. Such findings reinforce the belief that multiple factors are responsible for the obesity epidemic and that the optimal strategy to arrest the epidemic will be multifactorial. Because many of these factors are beyond the control of individuals (eg, size of portions served in restaurants, lack of information on calorie content at point of purchase, presence of sidewalks, adequate streetlights after dark), substantial changes to the environment will be required. Furthermore, the obesity epidemic highlights the importance of primary prevention efforts in children so that adverse diet and lifestyle behaviors do not become habits.
For individuals to adhere to a healthy diet and lifestyle, the AHA Nutrition Committee strongly believes that substantial changes to the environment must occur. In its deliberations, the Nutrition Committee identified several changes that it considers high priority and that should help achieve the AHA’s strategic goals of reducing CVD risk in the general population. Not surprisingly, several target groups are involved. A list of the changes by target group is presented in Table 5.
TABLE 5. High-Priority Recommendations to Facilitate Adoption of AHA 2006 Diet and Lifestyle Recommendations
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Conclusions |
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Appendix |
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Palm and Download Tools
dms/admehg3.html
Your Guide to Lowering Blood Pressure with DASH. http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/index.htm
American Heart Association Cookbooks
AHA Web Sites
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Footnotes |
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This statement was approved by the American Heart Association Science Advisory and Coordinating Committee on April 26, 2006. A single reprint is available by calling 800-242-8721 (US only) or writing the American Heart Association, Public Information, 7272 Greenville Ave, Dallas, TX 75231-4596. Ask for reprint No. 71-0365. To purchase additional reprints: up to 999 copies, call 800-611-6083 (US only) or fax 413-665-2671; 1000 or more copies, call 410-528-4121, fax 410-528-4264, or e-mail kelle.ramsay@wolterskluwer.com. To make photocopies for personal or educational use, call the Copyright Clearance Center, 978-750-8400.
Expert peer review of AHA Scientific Statements is conducted at the AHA National Center. For more on AHA statements and guidelines development, visit http://www.americanheart.org/presenter.jhtml?identifier=3023366.
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References |
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-linolenic acid, benefit
cardiovascular disease outcomes in primary- and secondary-prevention
studies: a systematic review. Am J Clin Nutr. 2006; 83: 5–17.
per day
cup dried fruit; 
cup (1