High blood pressure directly
increases the risk of coronary heart disease (which leads to heart attack) and
stroke, especially along with other risk factors.
High blood pressure can occur in children or
adults, but it's particularly prevalent in African Americans, middle-aged and
elderly people, obese people, heavy drinkers and women taking oral
contraceptives. People with diabetes mellitus gout or kidney disease have a
higher frequency of hypertension.
High blood pressure usually has no specific
symptoms and no early warning signs. It's truly a "silent killer." But
a simple, quick, painless test can detect it.
How does medicine help control high blood
Many medications, known as antihypertensives ,
are available to lower high blood pressure. Some, called diuretics , rid the
body of excess fluids and salt (sodium). Others, called beta blockers, reduce
the heart rate and the heart's output of blood.
Another class of antihypertensives is called
sympathetic nerve inhibitors. Sympathetic nerves go from the brain to all parts
of the body, including the arteries. They can cause the arteries to constrict,
raising blood pressure. This class of drugs reduces blood pressure by inhibiting
these nerves from constricting blood vessels.
Yet another group of drugs is the vasodilators .
These can cause the muscle in the walls of the blood vessels (especially the
arterioles) to relax, allowing the vessel to dilate (widen).
Other classes of drugs used to treat high blood
pressure are the angiotensin
converting enzyme (ACE) inhibitors, angiotensin II receptor blockers
and the calcium antagonists. The ACE inhibitors interfere with the body's
production of angiotensin, a chemical that causes the arteries to constrict, and
the angiotensin II receptor blockers block the effects of angiotensin. The
calcium antagonists can reduce the heart rate and relax blood vessels.
In most cases these drugs lower blood pressure.
Quite often, however, people respond very differently to these medications.
That's why most patients must go through a trial period to find out which
medications work best with the fewest side effects.
People with high blood pressure should remember
these key points:
- Follow your healthcare provider's
- Stay on your medication.
What about diet and lifestyle changes?
Dietary and lifestyle changes also may help
control high blood pressure. Before drugs are prescribed, these methods are
often recommended for people with only mildly elevated blood pressure.
The American Heart Association Nutrition
Committee has stated that to maximize the beneficial effects of diet on blood
- Avoid high intakes of salt.
- Make sure to eat enough fruits, vegetables,
and fat-free and low-fat dairy products.
Such diets are rich in potassium, calcium,
magnesium and protein, and low in total fat, saturated fat and cholesterol. Some
people with mild hypertension can lower their blood pressure by reducing sodium
(salt) in their diet. This means avoiding salty foods and cutting down on the
amount of salt used in cooking and at the table.
Excessive alcohol intake (more than two ounces of
pure alcohol or two drinks per day) raises blood pressure in some people and
should be restricted. Alcoholic drinks are high in non-nutritious calories, so
if you're trying to lose weight, avoid them.
Statistics show that many people who have high
blood pressure are also overweight. If you're overweight or have gained weight
over time, you'll be advised to cut down on calories and lose weight. Your
doctor can prescribe a diet that's right for you. If you're given a diet, follow
it closely, including any recommendations about reducing your consumption of
alcohol. Often when people lose weight, their blood pressure drops, too.
Physical inactivity is a risk factor for heart
disease. In addition, a sedentary or inactive lifestyle tends to contribute to
obesity, a risk factor for both high blood pressure and heart disease. Regular
exercise helps control weight and lower blood pressure. Don't be afraid to be
active - exercise should definitely be part of your daily program. Besides
helping to reduce your risk of heart attack, it can also help you lose weight or
maintain a healthy weight.
For some people, weight loss, sodium reduction
and other lifestyle changes won't lower high blood pressure as much as it needs
to be lowered. If that's your situation, you'll probably need to take
What is diabetes mellitus?
Diabetes mellitus is the inability of the body to
produce or respond properly to the hormone insulin. The body needs insulin to
convert glucose ("blood sugar") to energy. Diabetes is defined as a
fasting plasma glucose of 126 mg/dL or more measured on two occasions.
The two major forms of the disease are type 1 and
type 2 diabetes. Type 2 diabetes, the most common form, usually appears in
adults, often in middle age. Type 2 diabetes is often associated with obesity
and may be delayed or controlled with diet and exercise. Obesity and physical
inactivity are two risk factors for type 2 diabetes. In a mild form, it can go
undetected for many years. Untreated diabetes can lead to a host of serious
medical problems, including cardiovascular disease.
The other form of diabetes mellitus is type 1 or
juvenile diabetes. It typically begins early in life. People with type 1
diabetes have a primary insulin deficiency and must take insulin to stay alive.
Diabetes is treatable, but even when glucose
levels are under control, diabetes greatly increases the risk of heart disease
and stroke. In fact, most people with diabetes die of some form of heart or
blood vessel disease. Part of the reason for this is that diabetes affects
cholesterol and triglyceride levels. Often people with diabetes also have high
blood pressure, increasing their risk even more.
When diabetes is detected, a doctor may prescribe
changes in eating habits, weight control and exercise programs, and even drugs
to keep it in check. It's critically important for people with diabetes to have
regular check-ups. Work closely with your healthcare provider to manage your
diabetes and control any other risk factors. For example, blood pressure for
people with diabetes should be lower than 130/85 mm Hg.
Diabetes is a major risk factor for stroke and is
now recognized as a major risk factor for coronary heart disease, which leads to
heart attack. People with diabetes may avoid or delay heart and blood vessel
disease by controlling the other risk factors. It's especially important to
control weight and blood cholesterol with a low-saturated-fat, low-cholesterol
diet and regular exercise. It's also important to lower high blood pressure and
Even when glucose levels are under control,
diabetes greatly increases the risk of heart disease and stroke. About
two-thirds of people with diabetes die of some form of heart or blood vessel
If you have diabetes, it's critically important
to work with your healthcare provider to manage your diabetes and control any
other risk factors you can.
Cholesterol is a soft, waxy substance found among
the lipids (fats) in the bloodstream and in all your body's cells. It's an
important part of a healthy body because it's used to form cell membranes, some
hormones and other needed tissues. But a high level of cholesterol in the blood
- hypercholesterolemia - is a major risk factor for coronary heart disease,
which leads to heart attack.
Cholesterol and other fats can't dissolve in the
blood. They have to be transported to and from the cells by special carriers
called lipoproteins . There are several kinds, but the ones to be most concerned
about are low-density lipoprotein (LDL) and high-density lipoprotein (HDL).
What is LDL cholesterol?
Low-density lipoprotein is the major cholesterol
carrier in the blood. If too much LDL cholesterol circulates in the blood, it
can slowly build up in the walls of the arteries feeding the heart and brain.
Together with other substances it can form plaque, a thick, hard deposit that
can clog those arteries. This condition is known as atherosclerosis . A clot
(thrombus) that forms in the region of this plaque can block the flow of blood
to part of the heart muscle and cause a heart attack. If a clot blocks the flow
of blood to part of the brain, the result is a stroke. A high level of LDL
cholesterol (more than 130 mg/dL) reflects an increased risk of heart disease.
That's why LDL cholesterol is often called "bad" cholesterol. Lower
levels of LDL cholesterol reflect a lower risk of heart disease.
What is HDL cholesterol?
About one-third to one-fourth of blood
cholesterol is carried by high-density lipoprotein or HDL. Medical experts think
HDL tends to carry cholesterol away from the arteries and back to the liver,
where it's passed from the body. Some experts believe HDL removes excess
cholesterol from atherosclerotic plaques and thus slows their growth. HDL
cholesterol is known as "good" cholesterol because a high level of HDL
seems to protect against heart attack. The opposite is also true: a low HDL
level (less than 35 mg/dL) indicates a greater risk.
What is Lp(a) cholesterol?
Lp(a) is a genetic variation of plasma LDL. A
high level of Lp(a) is an important risk factor for developing atherosclerosis
prematurely. The way an increased Lp(a) contributes to disease isn't understood.
The lesions in artery walls contain substances that may interact with Lp(a),
leading to the buildup of lipids in atherosclerotic plaques.
What about cholesterol and diet?
People get cholesterol in two ways. The body -
mainly the liver - produces varying amounts, usually about 1,000 milligrams a
day. Another 400 to 500 mg (or more) can come directly from foods. Foods from
animals (especially egg yolks, meat, poultry, fish, seafood and whole-milk dairy
products) contain it. Foods from plants (fruits, vegetables, grains, nuts and
seeds) don't contain cholesterol. Typically the body makes all the cholesterol
it needs, so people don't need to consume it.
Saturated fatty acids are the chief culprit in
raising blood cholesterol, which increases your risk of heart disease. But
dietary cholesterol also plays a part. The average American man consumes about
337 milligrams of cholesterol a day; the average woman, 217 milligrams.
Some of the excess dietary cholesterol is removed
from the body through the liver. Still, the American Heart Association
recommends that you limit your average daily cholesterol intake to less than 300
milligrams. If you have heart disease, limit your daily intake to less than 200
milligrams. Still, everyone should remember that by keeping their dietary intake
of saturated fats low, they will also be able to significantly lower their
dietary cholesterol intake. Foods high in saturated fat generally contain
substantial amounts of dietary cholesterol.
People with severe hypercholesterolemia
may need an even greater reduction. Since cholesterol is present in all foods
from animal sources, care must be taken to eat no more than six ounces of lean
meat, fish and poultry per day and to use skim (fat-free) and low-fat dairy
products. High-quality proteins from vegetable sources such as beans are good
substitutes for animal sources of protein.
How does exercise (physical activity) affect
For some people, exercise affects blood
cholesterol level by increasing HDL ("good") cholesterol. A higher HDL
cholesterol is linked with decreased risk of heart disease. Exercise can also
help control weight, diabetes , and high blood pressure. Exercise that uses
oxygen to provide energy to large muscles (aerobic exercise) raises your heart
and breathing rates. Regular exercise such as brisk walking, jogging and
swimming also condition your heart and lungs.
Physical inactivity has been established as a
major risk factor for heart disease.
Even moderate-intensity activities, if done daily, help reduce your risk.
Examples are walking for pleasure, gardening, yard work, housework, dancing and
prescribed home exercise.
How does cigarette / tobacco smoke affect
Cigarette and tobacco smoke is one of the six
major risk factors of heart disease that you can change, treat or modify.
Smoking has been shown to lower HDL ("good") cholesterol levels.
How does alcohol affect cholesterol?
In some studies, moderate use of alcohol is
linked with higher HDL ("good") cholesterol levels. However, the
benefit isn't great enough to recommend drinking alcohol if you don't do so
What are antioxidant vitamins?
Considerable research has recently focused on how
antioxidant vitamins may reduce cardiovascular disease risk. Antioxidant
vitamins - E, C and beta carotene (a form of vitamin A) - have potential
health-promoting properties. Though the data are incomplete, up to 30 percent of
the population is taking some form of antioxidant supplement.
The American Heart Association doesn't recommend
using antioxidant vitamin supplements until more complete data are available. We
continue to recommend that Americans eat a variety of foods daily from all of
the basic food groups:
- six or more servings of breads, cereals, pasta
and starchy vegetables
- five servings of fruits and vegetables
- two to four servings of skim milk, low-fat
- up to six cooked ounces of lean meat, fish,
Eating a variety of foods low in saturated fat
and cholesterol will provide a rich natural source of these vitamins, minerals
Oxidation of low-density lipoprotein (LDL or
"bad") cholesterol plays an important role in the development of
atherosclerosis , the disease process that leads to heart attacks and strokes.
An increasing amount of evidence suggests that LDL cholesterol lipoprotein
oxidation and its biological effects can be prevented by using antioxidants -
both in the diet and in supplements. These data are from various sources: basic
science, epidemiology , experiments in animals and clinical investigations,
including limited clinical trials. The strongest evidence for using the
naturally occurring antioxidants to protect against the development of
cardiovascular disease is for vitamin E. It's weakest for vitamin C. Data on the
role of beta carotene are limited.
High intakes of vitamin E have been associated
with a decreased risk of coronary artery disease (CAD) incidence, according to
epidemiological studies. Animal studies also suggest that vitamin E can slow the
development of atherosclerosis. Furthermore, vitamin E inhibits LDL cholesterol
oxidation in test tube experiments and in human studies. Some epidemiological
studies suggest that vitamin C, which also inhibits lipoprotein oxidation, is
associated with reduced rates of clinical CAD.
Although beta carotene does not appear to inhibit
LDL cholesterol oxidation, early data suggest that it may reduce further
clinical events in subjects with established CAD.
One should not recommend using dietary
supplements of antioxidants to prevent cardiovascular disease until their effect
is proved in clinical trials that directly test their impact on CVD end points.
This caution is because the doses of these antioxidants that inhibited LDL
cholesterol oxidation in some studies are much larger than can be achieved by
diet alone. Beneficial effects must be demonstrated in randomized,
placebo-controlled clinical trials before recommending widespread use to prevent
Does the "Mediterranean" diet follow
AHA dietary guidelines?
There's no one, typical "Mediterranean"
diet. Diets vary greatly, not only between Mediterranean countries, but also
among different regions within a country.
In general, however, the diets of Mediterranean
peoples contain a higher percentage of calories from fat than the American Heart
More than half of these fat calories come from
monounsaturated fats (mainly from olive oil). Monounsaturated fat doesn't raise
blood cholesterol levels the way saturated fat does.
In the average Mediterranean diet, the
consumption of saturated fat is lower than the average in the American diet and
well within the AHA's Dietary Guidelines.
The incidence of, and death rates from, heart
disease in Mediterranean countries are lower than in the United States. This may
not be entirely due to the diet, though. Lifestyle factors such as more physical
activity, extended social support systems and drinking wine with meals may also
play a part.
Before advising that people follow an optimal
Mediterranean diet, we need to find out whether the diet itself or other
lifestyle factors are responsible for the lower deaths from heart disease. The
high fat content of the Mediterranean diet may increase the risk of obesity.
Measure Understanding FATS
There are three kinds of fats in the foods we
eat: saturated, polyunsaturated
and monounsaturated fatty acids. Most foods contain all three types of
fat, but in varying amounts. Only saturated fats and
dietary cholesterol raise blood cholesterol. A high level of cholesterol in the
blood is a major risk factor for coronary heart disease, which leads to heart
The body can use all three types of
fats, but the American Heart Association recommends that the average
person limit total fat intake (saturated, monounsaturated,
polyunsaturated) to no more than 30 percent of total calories.
Saturated fat intake should be limited
to 7-10 percent of total calories each day.
Polyunsaturated fat calories should be
up to 10 percent of total calories.
Monounsaturated fat intake should be
up to 15 percent of total calories.
What are recommended amounts of total fat and
saturated fat in grams?