Vitamin E: Background and Basics
Every cell needs vitamin E, but this fat-soluble substance is
most necessary for nerve cells, blood cells and skeletal muscle
cells. Without adequate vitamin E, peripheral neuropathy results.
Other deficiency symptoms include spinocerebellar ataxia, skeletal
myopathy, and pigmented retinopathy; premature infants are prone
to anemia due to vitamin E deficiency.
Vitamin E fights free radicals — unstable forms of
oxygen — thereby heading off oxidative damage, or oxidative
stress, to cells. As a cellular "bodyguard," vitamin
E protects cellular membranes and other fatty cellular components
by donating electrons to free radicals. Free radicals are
produced in the body as a result of everyday metabolism, and
in response to exposure to sunlight (ultraviolet rays), cigarette
smoke and air pollution.
After "taking a hit," vitamin E is regenerated
to continue protecting cells. It appears that vitamin E works
synergistically with other antioxidants, including glutathione
and vitamin C; these substances regenerate vitamin E to its
active state after vitamin E has reacted with, and neutralized
free radicals.
Increasingly, scientific evidence suggests high intakes of
vitamin E may reduce the risk of certain chronic diseases.
For example, vitamin E inhibits low-density lipoprotein (LDL)
oxidation, preventing conversion of LDLs to a stickier form
that promotes heart disease. According to the National Academy
of Sciences (NAS), a large body of animal studies supports
the antioxidant hypothesis of atherosclerosis.
The National Academy of Sciences (NAS) determined that there
is not enough research to support higher levels of vitamin
E intake. Therefore, in spite of the promise vitamin E holds
in heading off heart disease, the NAS does not recommend supplemental
vitamin E as a heart disease preventative for the general
population, nor does the organization recommend the same for
the prevention of any other diseases or the control of chronic
conditions, including the following:
• Diabetes. Oxidative stress may be linked to the development
of complications of diabetes. Vitamin E might play a role
in warding off the stress caused by elevated blood glucose
levels.
• Cancer. In theory, vitamin E may head off cancer by
squelching free radical damage to DNA.
• Compromised Immunity: Vitamin E may boost seniors'
immune systems.
• Cataract. In animal studies, vitamin E, and other
antioxidant vitamins protect against lens damage that leads
to cataract formation.
• Alzheimer's Disease: Large doses of supplemental vitamin
E show promise in slowing the progression of Alzheimer's disease,
which may have an oxidative stress component.
• Aging: By limiting oxidative stress, vitamin E may
slow the aging process.
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