Antioxidants are natural substances that exist as vitamins, minerals
and other compounds in foods. Vitamin E is considered an antioxidant
vitamin.
What are antioxidants?
Antioxidants fight substances, called free radicals that are produced
when your body uses oxygen, such as when breathing or when exposed
to substances such as cigarette smoke. Antioxidants have been
linked to disease prevention by helping to increase the function
of the immune system and possibly decrease the risk of heart disease,
infection, cancer and other diseases.
Because oxidation of low-density-lipoproteins (the “bad”
cholesterol) is an important step in the process of atherosclerosis,
it has led many investigators to ask what is the role of antioxidants
and heart disease? Atherosclerosis is the build-up of fat and
cholesterol deposits, called plaque, on the inside of the arteries
that leads to narrowing or blocking of the arteries if left untreated.
What is the role of antioxidants and cardiovascular disease?
Studies have shown that eating a diet rich in antioxidant-containing
foods, such as fruits, vegetables and whole grains, has been linked
to a reduced risk of cardiovascular (heart and blood vessels)
disease (Click here to learn more). Several studies have evaluated
the role of antioxidant vitamins, especially Vitamin E, in reducing
heart disease events and stroke in people who have a high risk
for these conditions.
Previous studies have shown conflicting results due to the low
doses of Vitamin E, few study participants, limited duration of
treatment and the inability to distinguish if the beneficial results
were due to the Vitamin E or other lifestyle factors.
HOPE Study
The Heart Outcomes Prevention Evaluation (HOPE) Study evaluated
a large number of patients (2545 women and 6995 men), aged 55
years and older, who were at high risk for cardiovascular events.
The study was conducted for 4 ½ years to determine the
role of vitamin E in those at high risk for primary or secondary
cardiovascular events.
Primary cardiovascular events included myocardial infarction (heart
attack), stroke, and death due to cardiovascular causes. Secondary
cardiovascular events included any event or hospitalization for
unstable angina (chest pain), heart failure, revascularization
(reestablishing blood supply), limb amputation, and complications
of diabetes or cancer. Patients were divided into two groups:
those that received 400 IU of vitamin E per day and those who
did not receive vitamin E, but rather a placebo.
The HOPE study showed that vitamin E did not reduce the incidence
of cardiovascular events in those at high risk for these conditions
during a follow-up period of 4 to 6 years.
Future studies will evaluate the use of vitamin E for a longer
period of time to determine if:
-
The
prolonged use (longer than 4 to 6 years) of vitamin E supplements
benefits those at high risk for primary or secondary cardiovascular
events
-
Vitamin
E supplements must be taken with other antioxidants to be beneficial
-
There
are other health benefits to vitamin E (such as decreasing the
risk of certain types of cancer or easing joint inflammation
from arthritis)
Vitamin
E - harmful effects?
Vitamin E can increase risk for bleeding. The minimum amount of
vitamin E it takes to affect blood clotting is about 30 IU. That
is far less than the 400 IU dose that most people actually take.
Most healthy people are not likely to run into problems with this,
but people who are already on a blood-thinner medication (such as
Coumadin, aspirin, or other platelet-inhibitors) or those who are
preparing for surgery, may have cause for concern.
Other studies have shown slightly less amount of cardioprotection
for those who take vitamin E. Dr. Eric Topol, Department Chairman
of Cardiovascular medicine states, “In fact, the Heart Protection
Study (HPS) indicated a slight trend toward harm in those patients
who took a combination of vitamin E, beta carotene, and vitamin
C.”
What
now?
"For now, there is no need to take vitamin E supplements to
reduce the risk of cardiovascular disease." Dr. Topol adds.
“If we could find a vitamin that helps people we would surely
recommend it. At this time, it is more important to decrease your
risk factors using more proven methods.”
To reduce your risk factors for cardiovascular disease, it’s
important to:
- Quit
smoking and using tobacco products
- Have
your doctor check your lipid profile
- Get
treatment, if necessary, to reach a lipid goal of LDL less than
100 and HDL greater than 45
- Eat
foods low in saturated fat and cholesterol and rich in fiber and
nutrients (including antioxidants)
- Exercise
regularly
- Control
high blood pressure and diabetes
- Achieve
and maintain an appropriate weight
- Ask
your doctor to do a blood test to detect high levels of homocysteine
and high-sensitivity c-reactive protein, substances that have
both been linked to an increased risk of heart disease
- Have
regular check-ups with your doctor
- Ask
your doctor about taking aspirin (between 80 and 160 mg once a
day)
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