One of the two major forms of vitamin E, the other being the tocotrienols. The d-alpha-tocopherol form is considered the gold standard for vitamin E use; it has the strongest effects and is kept in the body the longest.

The name tocopherol was coined in 1924 from the Greek roots tokos, childbirth, and pherin, to bring forth. The -ol suffix indicates that it is chemically an alcohol. This is because the earliest studies of vitamin E determined that when severely deprived of it, pregnant rats would reabsorb fetuses. To this day, the potency of different forms of the vitamin is determined by how much you have to give a rat to get her to bear her entire litter.