Vitamin E, Exercise May Slow Harmful Effects of Aging, Says University
of Florida Researcher
Aug. 5,
2003 - Nothing can turn back time, as aging adults well know, but a
University of Florida researcher reports a combination of exercise and
vitamin E may at least slow it down.
UF
nursing researchers found that older men and women who exercised
regularly and took vitamin E supplements became healthier and
significantly decreased their levels of a blood marker that signals
the destruction of certain cells by unstable molecular fragments
called free radicals. That process, known as free radical-induced
oxidative stress, contributes to aging and disease.
In
fact, study participants who did not exercise but still took vitamin E
also showed significant decreases in oxidative stress and blood
pressure. The study appears in the current issue of the journal
Biological Research for Nursing.
"The results of this study suggest that people who are over 40 can
benefit from regular moderate exercise and vitamin E to protect
against the destructive properties of free radicals and their effects
on our aging bodies," said James Jessup, the study's principal
investigator and an associate professor in UF's College of Nursing.
Jessup also is affiliated with UF's Institute on Aging.
Oxidation caused by free radicals damages cells, tissues and organs,
much as the process causes a car to rust or an apple to brown.
Exposure to ultraviolet radiation, smoke and environmental pollutants
increases production of free radicals.
Researchers elsewhere have shown that free radicals play a role in the
development of cancer, obstructed arteries, Alzheimer's disease and
some 200 other diseases, as well as in the aging process itself.
However, studies also have revealed that antioxidants, such as
beta-carotene and vitamins C and E, help protect the body.
"The body produces free radicals constantly," Jessup said. "When we
are young, however, our body also creates antioxidants to battle these
free radicals. Yet in our late 30s and early 40s, we begin to produce
more free radicals and fewer antioxidants."
Vitamin E is a powerful antioxidant that can be consumed in the diet,
Jessup said. Good sources of vitamin E include spinach, almonds and
avocadoes. But most people - old and young - are vitamin E deficient,
as it is difficult to get enough of the antioxidant from diet alone.
For that reason, Jessup said, older individuals are more susceptible
to the physiologic and physical effects of aging.
Over a two-year period, Jessup and his research team studied 59
healthy men and women ages 60 to 75 who lived in a community
retirement facility in North Central Florida and were not regularly
exercising. Half were randomly assigned to a group that exercised
routinely and half to a control group that did not. Participants in
each group were then randomly assigned to take daily vitamin E
supplements or placebos.
All study participants maintained their usual eating habits. Those in
the vitamin E groups were supplied with and asked to take 800
international units of vitamin E, well over the U.S. recommended daily
allowance of 30 international units. However, no specific guidelines
exist for older Americans, and previous research has shown that
exercise may increase the production of free radicals and the
requirements for dietary antioxidants such as vitamin E.
Both exercise groups completed 16 weeks of supervised endurance
exercise on treadmill, cycle and stair-climber machines for 60 minutes
twice a week, with intensity and duration increasing in the fourth and
fifth weeks of the regimen. The sedentary group did not change their
usual daily activities or begin an exercise routine.
Results showed that, on average, a key byproduct of free radical
damage in the two groups taking vitamin E was cut in half. In
addition, those in the sedentary group taking vitamin E did show a
significant reduction in their systolic blood pressure, which dropped
an average of almost seven points. The group who exercised and took
vitamin E had an average drop of about 15 points in their systolic
blood pressure and about 5 points in their diastolic blood pressure,
as well as increased weight loss and significant improvement in
resting oxygen uptake, a measure of cardiovascular fitness and
endurance. The sedentary group not taking vitamin E showed no
significant changes.
The two groups taking vitamin E did not differ in their concentrations
of a byproduct of free radical damage, leading researchers to
hypothesize that such damage can be prevented only up to a point, with
or without exercise. However, other benefits derived from exercise,
such as weight loss, improved cardiovascular health and lower blood
pressure, cannot be duplicated, Jessup said.
"To benefit, older adults do not need to be doing strenuous exercise,"
Jessup said. "Mowing the lawn, dancing, vacuuming - something that
will get your heart rate up for 30 minutes is enough. Even adults who
cannot physically perform this type of activity should take vitamin E
because of its clear benefits to aging and systolic blood pressure."
Results from the UF study and from others around the country indicate
that consuming antioxidants and getting the right amount of exercise
can help slow the aging process and protect against destructive free
radicals, Jessup said.
"Research by Dr. Jessup and others defining optimal intakes of vitamin
E is essential to our ability to provide sound recommendations,
especially for older adults, about dietary supplements that can
promote health and reduce the risk for chronic diseases," said Jeffrey
Blumberg, chief of the Antioxidants Research Laboratory at the Jean
Mayer U.S. Department of Agriculture Human Nutrition Research Center
on Aging at Tufts University.
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