I actually just found a study finding the opposite to what I was saying. https://www.ncbi.nlm.nih.gov/pubmed/23700248
However my concern with just supplementing alpha-tocopherol has to do with decreased absorption of the other forms from out competing the receptors rather then causing depletion of the other. The study didn't study the right question. Mixed tocopherols are more similar to real food rather then just straight synthetic alpha-tocopherol that most vitamin E products are made out of.
I don't really supplement vitamin E very much in my practice but to recommend mixed tocopherols for people who want to be on vitamin E long term. Of if I find good evidence to use it in a patient with a more unique diagnosis.
RE: Vitamin Wednesday #4 - Vitamin E [Eng/De]