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If you take vitamin E supplements you're not alone. According to a
recent survey, more than 37 million Americans take vitamin E supplements
every day.
What is so special about vitamin E? Do we need to take vitamin E
supplements or can we get all we need through foods? These and other
questions about vitamin E are discussed in a recent report issued by the
Food and Nutrition Science Alliance, entitled "What Consumers Need to
Know about Vitamin E." The following is a look at some of the questions
the FANSA report addressed.
What is vitamin E? Vitamin E is a powerful antioxidant that works to
protect cells in the body from damage caused by free radicals. Free
radicals are highly reactive substances that result from normal
metabolism as well as from exposure to factors in the environment like
cigarette smoke and ultraviolet light. They cause damage to body cells
by attacking the cell's membranes, proteins and DNA and ultimately
contribute to the development of health problems such as heart disease
and cancer.
Vitamin E is especially important in protecting blood cells, the nervous
system,
skeletal muscle and the retinas in the eyes from free radical damage.
Are some forms of vitamin E better than other forms? There are two main
groups of vitamin E compounds: the tocopherols and the tocotrienols,
each containing four isomers. Of these, the alpha-tocopherol isomer is
the only form of vitamin E that the human body can
use. While the body can absorb both natural and synthetic forms of
alpha-tocopherol,
natural forms, either from foods or natural-source supplements, are used
more efficiently.
How much vitamin E do you need? A person's daily requirement for vitamin
E varies with age, gender, overall health status and the amount of
polyunsaturated fats consumed in the diet. Polyunsaturated fats tend to
be easily oxidized; thus, if a person's diet is high in foods containing
polyunsaturated fats, their need for vitamin E is increased.
The recommended dietary allowance for vitamin E is 15 milligrams of
alpha-tocopherol daily. On average, American adults consume about 8 to
12 milligrams of vitamin E each day through their diet.
Supplements list vitamin E in terms of international units, or IUs.
Because of differences in potency, 15 milligrams of alpha-tocopherol is
equivalent to 22 IU of d-alpha tocopherol (natural form) or 33 IU of
d,l-alpha tocopherol (synthetic form).
What are the possible benefits of vitamin E? Results from scientific
studies suggest that vitamin E may help lower the risk of several
chronic conditions including heart disease, stroke, diabetes and
cataracts. An increased intake of vitamin E may also slow the oxidation
of bad (LDL) cholesterol, prevent blood clot formation, enhance immune
response and benefit the nervous system. However, while the potential
benefits of vitamin E seem promising, they have not been proven
conclusively.
Much still remains unknown and under investigation.
What are the best dietary sources of vitamin E? The best sources of
vitamin E are vegetable oils such as sunflower, canola, corn, soybean
and olive oil. Nuts, sunflower seeds and wheat germ are also good
sources. Other sources of vitamin E are whole grains, fish, peanut
butter, and green, leafy vegetables.
Do you need a vitamin E supplement? Due to a lack of sufficient
evidence, no national scientific bodies have recommended vitamin E
supplements. If you choose to take a vitamin E supplement, be sure to
tell your health care provider because of possible drug interactions.
Dosages greater than 1000 milligrams daily are not recommended because
they may cause bleeding disorders in people taking blood-thinning
medications.
The complete FANSA report on vitamin E can be viewed online at
www.ift.org.
For more information, contact your local
Colorado State University Extension office.
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