VITAMIN E
Vitamin
E is a potent antioxidant with proven anti-cancer activity that also
has proven protective effects against cardiovascular disease. In its
natural food state, Vitamin E is actually a family of seven
different tocopherols, but the form used for most supplements and
medical studies is the alpha-tocopherol form. Vitamin E was
originally isolated from wheat germ oil. Its fat-soluble properties
allow Vitamin E to function as a potent antioxidant in both the
fat-soluble and the water-soluble parts of the cell membrane.
Vitamin E helps maintain cell wall integrity and preserve energy
metabolism of the cell by inhibiting lipid peroxidation of cell
membranes. Vitamin E is also and immune-enhancer and protects
against pollution-derived lung damage.
The
anticancer activity of Vitamin E is thought to be via its
antioxidant action and immune enhancement properties. Vitamin E
works synergistically with other potent cellular antioxidants
including selenium, Vitamin C, zinc and others. For example, Vitamin
E enhances the cancer preventive effect of selenium on
chemical-induced breast caccer in rats, acts with zinc as a
stabilizer of cell membranes, requires selenium for adequate
absorption from the gastrointestinal tract, is destroyed more
readily by free radicals in the presence of copper or iron unless
adequate Vitamin C is present, and is required to maintain normal
levels of Vitamin A in the liver and plasma.
Vitamin
E has been shown to prevent the free-radical oxidation (damage) of
cholesterol, considered to be an early step in the development of
coronary artery disease. Some clinical trials have found that
Vitamin E supplements can reduce the risk of coronary artery disease
and heart attacks while others have not. Because heart disease takes
many years to develop, long-term intake of Vitamin E may play a role
in its prevention.
In
a study of 307 women ranging from 30 to 69 years of age, those with
either low intake or low blood levels of Vitamin E were far more
likely to have atherosclerotic plaques at the carotid bifurcation
and, conversely, those with the highest intake or blood levels of
the Vitamin E were least likely to have early signs of
atherosclerosis. The women with the lowest blood levels of Vitamin E
were twice as likely to have signs of early cardiovascular disease.
Vitamin
E has been shown to be one of the strongest protectors against the
environmental pollutants, ozone and nitric oxide. Nitrites are major
sources of free radical damage to cells. Nitrites, like many
chemicals, are not carcinogenic until they are converted to an
active form in the body. In some cases Vitamin E can prevent the
conversion of inactive forms of such cancer causing substances to
active forms.
Vitamin
E also prevents the action of tumor promoting and tumor initiating
agents which are present in the environment and diet.
Vitamin
E influences the effectiveness of many drugs currently used in
cancer treatment. In vitro studies, Vitamin E acetate in combination
with vincristine, 5-fluorouracil, adriamycin, or chlorozotacin
produces a synergistic effect, whereas Vitamin E in combination with
bleomycin,
I-(2-cholrethyl)-3-cyclohexyl-1-triazeno-imidazole-4-carboxamie (DTIC),
mutamycin or (cis-diamine) dichloro-platinum II (cis-platinum II)
produces an additive effect in inhibiting growth of neuroblastoma
cells.
In
glioma cell cultures, Vitamin E acetate in combination with
vincristine or CCNU produces a synergistic effect, whereas Vitamin E
in combination with bleomycin, 5-fluorouracil, adriamycin, DTIC,
mutamycin and cis-platinum produces an additive effect on the
inhibition of growth.
These
studies suggest that the effectiveness of the interaction of Vitamin
E with cancer chemotherapeutic drugs depends upon tumor form and
type of drug. Vitamin E also enhances the effect of some naturally
occurring substances such as prostaglandins and sodium butyrate on
neuroblastoma cells in vitro. The relevance of the above results in
humans is not known at this time.
Vitamin
E appears to protect against radiation damage and to also protect
against radiation-induced cancers in vitro. Vitamin E protects cells
from the toxicity of certain heavy metals, including mercury-induced
brain damage. Vitamin E also protects against lung damage generated
by cigarette smoke.
Vitamin
E appears to protect against various cancers through several
actions: Vitamin E kills tumor cells directly, enhances the effect
of tumor therapeutic agents (drug, radiation and heat), reduces the
toxic effect of tumor cells, and enhances normal immune functions.
Vitamin
E's ability to reduce free radicals may slow aging and reduce risk
of cancer risk.
Selected References
Battisti
C et al. Vitamin E serum levels and gastric cancer: results from a
cohort of patients in Tuscany, Italy. Cancer Lett 151(1):15-8, 2000.
Bostick
RM et al. Reduced risk of colon cancer with high intake of vitamin
E: the Iowa women's health study. Cancer Res 53:4230-4237, 1993.
Gunawardena
K et al. Vitamin E and other antioxidants inhibit human prostate
cancer cells through apoptosis. Prostate 44(4):287-95, 2000.
Horvath
PM et al. Synergistic effect of vitamin E and selenium in the
chemoprevention of mammary carcinogenesis in rats. Cancer Res
43:5335- 5341, 1983.
Knekt
P et al. Serum vitamin E, serum selenium, and the risk of
gastrointestinal cancer. Int J Cancer 42:846-850, 1988.
Meydani
SN et al. Vitamin E supplementation enhances cell-mediated immunity
in healthy elderly subjects. Am J Clin Nutr 52:557-563, 1990.
Wald
NJ et al. Serum vitamin E and subsequent risk of cancer. Br J Cancer
56:69-72, 1987.
>> NOTE: Each serving of Ellagic Insurance Formula contains 400IU of Vitamin E.
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