Alpha-tocopheral is a type of vitamin E that is essential for maintaining good health. It is commonly found in vegetable oils, nuts, seeds, and green leafy vegetables. There are various other names that are used interchangeably for alpha-tocopheral, including D-alpha-tocopherol, RRR-alpha-tocopherol, and natural vitamin E. These names are used to distinguish it from synthetic forms of vitamin E, such as DL-alpha-tocopherol. In addition, tocopherol is sometimes referred to as the parent compound of all tocopherols and tocotrienols. Keeping track of these different terms can be useful for understanding the labels on vitamin E supplements or seeking out natural sources of vitamin E in your diet.