I have a question in regard to absorption of a powdered, pelleted, and liquid vitamin E. Do they have the same potency and absorption? Also, I am concerned about using vitamin E in combination with selenium, since it appears that too much selenium can be a problem as well.
In regard to vitamin E, the factor that most influences absorption is the type of vitamin E, whether it is natural or synthetic. On the label it will state either d-alpha tocoperol (natural vitamin E) or dl-alpha tocopherol (synthetic vitamin E).
The next property that influences absorption is the form. Natural vitamin E in oil form is usually an acetate (powder, gel caps, or oil), while liquid vitamin E is sometimes micellized to make it water-soluble. Other natural liquid vitamin E products, such as Nano-E, may be nanodispersed. More on vitamin E and the process of nanodispersion can be found here. In absorption studies, the relative differences are charted in Figure 3 on the aforementioned page. Looking at the graph, the “natural acetate” would be what is found in gel caps of natural vitamin E that you find at the store or the powdered natural vitamin E, the “natural alcohol” is a micellized liquid, and the “Nano•E” is the nanodispersed KERx product.
It is easier to tailor vitamin E supplementation to suit the work effort if it is not combined with selenium. The margin of safety is wide for vitamin E but narrow for selenium. Most diets are sufficient in selenium, but vitamin E can be variable because of the different availabilities of the various forms of vitamin E. Green grass is loaded with natural vitamin E. Most commercial feeds are made with synthetic vitamin E, so it is always good to check the tag if there is a question.