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The relationship between diet and heart
disease has been the focus of much debate and scientific
research for over a century. Many foods and various diet
patterns have fallen in and out of favor almost in keeping
with the change of seasons. With each new headline,
manufacturers have responded with new products, from fat-free
egg substitutes, omega-3 enriched eggs, cholesterol-free
margarine to calcium-fortified spreads. If you find yourself a
bit confused about what to eat as you read the headlines, you
are not alone.
There are modifiable risk factors for developing coronary
heart disease, which can lead to a heart attack or stroke.
Some of these risk factors, such as high blood cholesterol,
high blood pressure (hypertension), obesity (defined as a BMI
greater than 30) and diabetes, can significantly be influenced
by the foods we eat and our dietary pattern. This is
especially important since; cardiovascular disease is the
leading cause of deaths.
Researchers now know more about the controllable risk
factors for coronary artery disease (CAD) than many other
diseases. These guidelines encourage the following:
- A heart-healthy eating pattern that includes a variety
of fruits, vegetables, grains, low-fat or non-fat dairy
products, fish, legumes (beans), poultry and lean meats.
- Achieving and maintaining a healthy body weight by
balancing energy intake (calories eaten) with energy needs.
- Participating in regular physical activity for 30 to 60
minutes on most if not all days.
- Smoking cessation.
- Achieving and maintaining desirable blood lipid profile
by limiting foods high in saturated fats, trans fats and
cholesterol; and substituting healthier fats such as
monounsaturated and polyunsaturated fats from vegetables,
fish, legumes and nuts.
- Achieving and maintaining normal blood pressure levels
by limiting salt and alcohol intake, maintaining a healthy
body weight and eating a heart-healthy diet.
A heart-healthy eating plan includes a wide variety of
foods high in complex carbohydrates, fiber and vitamins and
minerals. It is also low in fat, cholesterol and salt. This
article describes a heart-healthy, balanced diet that can be
used to help reduce the risk of cardiovascular disease and
related conditions such as obesity (body mass index [BMI]
greater than or equal to 30), high blood pressure
(hypertension) and atherosclerosis (hardening and narrowing of
the arteries).
What are
the basic guidelines to a heart-healthy
diet?
Formerly named Step 1 and Step 2 diets, the
revised guidelines focus on the need to achieve and maintain a
healthy body weight through healthy food choices and dietary
lifestyle practices.
For higher-risk individuals, such as those with diabetes,
cardiovascular disease or lipid disorders for example, they
recommend following diet which is a more individualized
approach involving medical nutrition therapy. The TLC diet
replaces the former Step 2 recommendations. To achieve and
maintain a heart-healthy eating pattern, the following
guidelines are recommended:
Eat a variety of fruits and
vegetables. Choose five or more servings of whole fruits and
vegetables – especially dark green, orange or yellow – each
day.
Eat a variety of grain products, especially whole grains,
choosing six or more servings per day.
Include low-fat or fat-free dairy products, fish (at least
two servings per week), legumes (beans), poultry (skin
removed) and lean meats.
Limit cholesterol-raising fats such as saturated fats and
trans fats. Limit full-fat dairy products, high-fat meats,
fried foods, products made with partially hydrogenated
vegetable oils, tropical oils (e.g., palm kernel oil, palm oil
or coconut oil) and egg yolks. Instead, choose fats and oils
with two grams or less saturated fat per tablespoon, low-fat
or non-fat dairy products, and lean meats. In addition, limit
dietary cholesterol intake to less than 300 mg per day.
Balance the total number of calories (energy) you eat with
the total energy used each day to maintain a healthy body
weight.
Maintain a level of physical activity that keeps you fit
and matches your energy (calorie) intake to maintain a healthy
body weight. Participate in at least 30 minutes of physical
activity on most days. For weight loss, maintain an activity
level that exceeds the amount of calories that you eat every
day.
Limit intake of foods that are high in calorie content and
low in nutrition including foods with a high sugar content
such as soft drinks or candy.
Consume less than 2,400 milligrams of sodium per day. This
is about a teaspoon of salt per day. People with high blood
pressure (hypertension) should strive for even lower intake.
Avoid salty foods and cut back on adding salt to your foods
during or after cooking. Check food labels for salt content of
packaged foods.
Limit alcohol intake to no more than one alcoholic drink
per day for women and no more than two drinks for men. (One
drink= 12 ounces of beer, 4 ounces wine, 1.5 ounce of 80-proof
spirits or one ounce of 100-proof spirits.)
These
guidelines encourage eating a wide variety of foods high in
complex carbohydrates from whole grains, fiber and vitamins
and minerals. This diet is also low in fat, cholesterol and
salt. Eating excessive amounts of foods (especially foods high
in saturated fat, sugar and salt) should be avoided. Every
meal or dinner party may not meet all these guidelines.
Instead of concentrating on each meal, these guidelines should
be applied to achieve an overall heart-healthy eating pattern.
It is important to maintain a healthy body weight by
balancing calorie intake with calories used and to participate
in regular exercise. Following a heart-healthy diet, achieving
a healthy body weight and becoming physically active can
reduce heart disease risk as well as other chronic health
problems such as type 2 diabetes, osteoporosis (bone loss) and
some forms of cancer.
How can an
unhealthy diet harm the heart?
Food provides the
human body with the building blocks (nutrients) and fuel
(energy) that are required for healthy function. Food is more
than essential, however. For many, it is truly enjoyed on an
emotional level – to be savored as an experience and viewed as
a work of art.
Unfortunately, food has been linked to both emotional and
physical problems. From an emotional perspective, food can be
used to fill a feeling of emptiness or to gain a sense of
control, sometimes leading to eating disorders such as
anorexia nervosa. From a physical perspective, the quality of
one’s diet can be a powerful contributor to the development of
many diseases, of which heart-related problems are among the
most serious. Diets that are high in cholesterol and certain
fats and oils greatly increase the risk of the following:
- Hardened and narrowed arteries (atherosclerosis) as
early as childhood
- High blood pressure (hypertension)
- Obesity (defined as a BMI greater than 30), which can
put tremendous strain and additional workload on the heart.
What
is a balanced diet?
A balanced diet provides the
body with the energy and nutrients it needs to stay in good
working order. It also prevents an excess of non-nutritious or
potentially harmful substances from causing damage to organs,
tissues and blood vessels. In general, a balanced
heart-healthy diet should contain the following:
- Total Energy: Balance of energy (calorie) intake and of
calories used each day to maintain a healthy body weight and
to prevent excessive weight gain. To estimate the total
energy needs to maintain one's current body weight, multiply
the number of pounds you weigh by 15 calories if you are
moderately active, (multiply by 13 calories if you are less
active).
- Protein: Approximately 15 percent of total energy
- Carbohydrate: 50 to 60 percent of total energy
- Total fat: 25 to 35 percent of total energy
- Saturated fat: Less than seven percent of total energy
- Polyunsaturated fat: Up to 10 percent of total energy
- Monounsaturated fat: Up to 20 percent of total energy
- Fiber: 20 to 30 grams or more per day
- Vitamins and minerals
- Water
Furthermore, the amount of these
substances needed by the body is taken into account. For
instance, carbohydrates are macronutrients, so they are
required in greater amounts than micronutrients such as
vitamins or minerals.
The Food Guide Pyramid illustrates the recommended number
of servings that individuals should eat in each category and
provides a relative indication as to the fat and added sugars
found in each food. The food categories, suggested daily
servings*, examples of serving sizes as well as heart-healthy
options are as follows:
Food
Groups
(suggested daily servings*)
|
Serving Sizes |
Heart-Healthy
Choices |
Bread, cereal, rice and pasta
( 6 to
11 servings/day) |
1 slice of bread
1 cup of cereal
½
cup of cooked cereal, rice or pasta |
Choose low-fat, whole grain breads,
cereals and grains (rolled oats, whole wheat bread,
brown rice, barley, etc.). Avoid added salt, sugar or
fats (e.g., saltines, croissants, biscuits, muffins,
donuts). |
Vegetables
(3 to 5 servings)
|
1 piece of medium-size fruit
½ cup of
chopped, cooked or canned fruit
¾ cup of 100 percent
fruit juice
|
Choose a variety of fruits and
unsweetened fruit juices. |
Milk, yogurt and cheese
(2 to 3
servings)
|
1 cup of milk or yogurt
1-½ ounces of
natural cheese
2 ounces of processed cheese
|
Choose lower fat dairy products such as
low-fat or fat-free milk and yogurt, low-fat cheese
(less than 20 percent milkfat) or low-fat cottage
cheese. |
Meat, poultry, fish, beans, eggs and
nuts
2 to 3 servings
|
2 to 3 ounces of cooked lean meat
½
cup of cooked dry beans
½ cup of tofu
A 2-½ ounce
soy burger
1 egg
1/3 cup nuts
|
Choose lean meats with all visible fat
trimmed. Eat fish at least twice a week. Instead of
meat, try to substitute beans such as lentils, black
beans, or chick peas a few times per week. Avoid high
fat, high cholesterol meats; such as bacon, sausage,
organ meats or pate. Limit egg yolks to two or less per
week. |
Fats, oils and sweets
Only use
sparingly
(amount of fats/oils adjusted to calorie
level)
|
1 tsp vegetable oil
1 Tbsp salad
dressing
2 tsp mayonnaise
|
Choose oils high in unsaturated fats
such as canola, corn, safflower or olive oils. Liquid or
soft margarines without hydrogenated fats and less than
2 grams of saturated fat per tablespoon. Limit butter,
hard margarines, lard, shortening or coconut milk. Avoid
"empty calorie" sweets such as soft drinks or
candy. |
* The number of servings will vary with each individual,
based on factors such as age, sex and level of physical
activity. This is because the number of servings is based on
the total number of total calories required, ranging from
about 1,600 calories for children and women to about 2,800
calories for teenage boys and active adult males.
Which
dietary factors affect heart health?
The goal of a
heart-healthy diet is to eat a variety of foods that help to
obtain and maintain a healthy body weight, healthy blood lipid
profile and to keep blood pressure under control. One strategy
for improving your blood presuure and blood lipid profile is
to eat a well-balanced heart-healthy diet. Based on decades of
scientific research, the diet developed to lower heart disease
risk makes the following recommendations:
- Total fat should make up 25 to 35 percent of daily
energy intake. Since most foods high in fat are also high in
saturated fat and calories, limiting total fat intake may
help to maintain healthy weight and blood cholesterol
levels.
- Reduce saturated fat in the diet to less than 7 percent
of total energy (calorie) intake. Studies have shown that
diets high in saturated fat increase LDL cholesterol and
total cholesterol levels. The good news is that the opposite
is also true and reducing the amount of saturated fat you
eat can help lower your blood levels of LDL cholesterol and
total cholesterol.
- Trans fats should be limited as much as possible in the
diet. Trans fats raise LDL cholesterol, increasing the risk
of heart disease. Avoid hydrogenated or partially
hydrogenated fats (listed under the ingredients list on food
labels), hard margarines or packaged foods prepared with
these ingredients.
- Monounsaturated fats derived from plant oils and nuts
can replace saturated fats in your diet up to 20 percent of
total energy. Monounsaturated fats lower LDL or "bad"
cholesterol without lowering high-density lipoprotein (HDL,
"good" cholesterol) levels when substituted for saturated
fats in the diet. People consuming a traditional
Mediterranean diet high in fruits, vegetables, whole grains,
fish and unsaturated fats (especially monounsaturated fat
from olive oil) generally have lower rates of cardiovascular
disease.
- Polyunsaturated fats can also replace saturated fats in
the diet up to 10 percent of total energy. These fats lower
LDL or "bad" cholesterol and can cause small reductions in
HDL or "good" cholesterol when substituted for the saturated
fats in the diet. It is important that the dietary sources
of polyunsaturated fats come from liquid vegetable oils and
semi-liquid margarines that are low in trans fats.
- Consume less than 200 milligrams per day of dietary
cholesterol. Dietary cholesterol is found only in foods that
are made from or contain animal products. Reducing dietary
cholesterol intake can help to lower LDL cholesterol levels.
- Weight loss is encouraged in overweight patients, with
the goal of achieving and maintaining a healthy body weight
(body mass index between 18.5 and 25). Weight loss of even a
few pounds in overweight patients can reduce LDL cholesterol
levels. To learn more about this topic, see Weight Loss
Overview.
- Carbohydrates should make up 50 to 60 percent of total
daily energy intake. Very high intakes of carbohydrates
(greater than 60 percent) may lower HDL or "good"
cholesterol levels and increase triglyceride levels. Sweets
or even “low-fat” foods, if high in sugar content, can cause
weight gain, not to mention tooth decay. Sweets (foods high
in simple sugars) such as cakes, candies, sweetened fruit
beverages and regular sodas tend to be high in calories and
low in essential nutrients (i.e., “empty” calories). Instead
choose complex carbohydrates that are also a good source of
dietary fiber.
- Soluble fiber (five to 10 grams per day) can help to
lower LDL and total cholesterol levels. Foods high in
soluble fiber content include fruits and vegetables, legumes
(beans) and cooked cereals such as oats and grains.
- Plant stanols/sterols intake of 2 to 3 grams a day can
help to lower “bad” or LDL cholesterol levels. Sources are
foods derived from plants such as fruits and vegetables.
Margarine spreads that contain stanol/sterol esters are also
available. These speads may also lower beta-carotene levels
and are designed mainly for people diagnosed with high
cholesterol levels. The presence of plant stanols/sterols is
listed on food labels.
- Drinking alcohol to excess has many harmful effects,
including raising the risk of high blood pressure
(hypertension) and adding “empty” calories to your diet.
However, some studies have shown that moderate alcohol
consumption (i.e., no more than one drink per day for women
and no more than two drinks a day for men) may actually
reduce the risk of heart disease. The choice of alcohol as a
preventive tool, however, should be balanced with its
potential risks. Therefore, everyone is encouraged to talk
to their physician. People who are encouraged to avoid
alcohol include minors, individuals with a family medical
history of alcoholism, pregnant women and persons on certain
medications.
- Limit salt intake to 2400 milligrams a day. This is
about a teaspoon of salt per day. Salt contributes to high
blood pressure (hypertension). The Dietary Approaches to
Stop Hypertention (DASH) trial provided evidence that a diet
high in fruits, vegetables, low-fat dairy products, whole
grains, poultry, fish and nuts and low in fat, red meat,
sweets can favorably influence blood pressure. When this
diet pattern is combined with reduction in salt intake the
benefits are additive and blood pressure is lowered even
more.
Why are
nutrition labels important?
For many, the challenge
of planning a healthy diet may be in knowing what foods to
prepare to stay within a given range of calories, fats and so
forth. It may require developing daily or weekly menus in
advance, and a food log may also be helpful. Fortunately,
keeping track of the amount of nutrients in certain foods is
easy. Food values can be found on everyday food products —
right on the label. By learning how to read a nutrition label,
it will be easier to prepare a heart-healthy meal.
The nutrition label, titled Nutrition Facts, is required by
law to be included on the labels of most foods that are not
considered “fresh,” though some fresh products may include the
information by choice. Certain foods are exempt from mandatory
labeling. These foods include restaurant-prepared foods,
ready-to eat bakery or deli foods and products with no
nutritional value (e.g., spices or coffee beans). The
nutrition label gives information about the following:
- Total calories
- Calories from fat
- Total fat
- Saturated fat
- Cholesterol
- Sodium
- Total carbohydrates
- Dietary fiber
- Sugars
- Protein
- Vitamin A
- Vitamin C
- Calcium
- Iron
The amount of each of these is listed by actual content
(usually measured in milligrams or grams). The government
suggests that people consume of each nutrient per day, based
on a 2,000-calorie diet. So if a cup of yogurt only satisfies
30 percent of calcium, then in addition to eating that cup of
yogurt, someone would also need to get another 70 percent of
their daily need for calcium from other sources through the
day. The label also provides portioning information (whether
there is one serving in the whole package/container, or
multiple servings per package/container.)
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