Even though the RDA for vitamin E is really quite low, many people do not consume this in their diet alone.
For the d-alpha tocopheral form of this vitamin, 1 mg. equals 1.49 IUs. The different forms of vitamin E have various potencies, with d-alpha the most active and most prevalent in nature. Vitamin E extraction, purity, and activity also vary. The best forms, in my opinion, are those that contain the natural, unesterified d-alpha tocopherol along with the other (beta, gamma, and delta) naturally occurring tocopherols. This type of E is not
RDAs for Vitamin E (in IUS)
easy to find because it is more difficult and costly to produce. The vitamin E palmitates and acetates are synthetic water-dispersible forms of vitamin E that have a good level of activity and are often easier to take, as they can be taken with other vitamins. Vitamin E oil is taken ideally in the morning before breakfast or at night before bed. It can also be taken after meals containing some fat. Approximately 400–600 IUs is used preventively, whereas for therapeutic effects, an amount between 800–1600 IUs daily is suggested. With therapeutic uses of vitamin E, it is best to start with a low level and gradually increase it. Levels over 1,600 IUs per day are not recommended unless there is close medical supervision.