What is it?
Vitamin E is the collective name for a set of 8 related tocopherols and tocotrienols, which are fat-soluble vitamins with antioxidant properties. Of these, á-tocopherol has been most studied as it has the highest bioavailability, with the body preferentially absorbing and using this form.
It has been claimed that á-tocopherol is the most important lipid-soluble antioxidant, and that it protects cell membranes from oxidation by reacting with lipid radicals produced
in the lipid peroxidation chain reaction. This would remove the free radical intermediates and prevent the oxidation reaction from continuing. The oxidised á-tocopheroxyl
radicals produced in this process may be recycled back to the active reduced form through reduction by other antioxidants, such as ascorbate, retinol or ubiquinol.
The other forms of are less well-studied, although ã-tocopherol
is a nucleophile that may react with electrophilic mutagens, and tocotrienols may have a specialized role in protecting neurons from damage. However, the roles and importance of the various forms of this supplement are presently unclear, and it has even been suggested
that the most important function of this supplement is as a signaling molecule, and that it has
no significant role in antioxidant metabolism.
Much more than Vitamin E is discussed at the Natural Source Vitamins Homepage