The Daily Mail recently (Nov 2017) reported on some science extolling the benefits of Vitamin E where Asthma is concerned. The Article even floated the idea that Vit E might become a Treatment for Asthma.
The Science / Data ‘Source’ (mentioned in the Daily Mail Article I’ve linked to below) stated that the ‘Gamma Tocopherol’ Content of Vitamin E was responsible for the benefit to Asthmatics.
However, another Science Article, only a couple of years older from a different ‘professional’ source (link also below) seems to reach the opposite conclusion, i.e. that ‘Gamma Tocopherols’ in Vitamin E can make your Asthma worse by up to 10% - but that Alpha Tocopherols in Vitamin E could reduce your Asthma.
Bottom line? Seems that some forms of Vitamin E might help your Asthma but others may make it worse.
As to which is the right kind of Vit E (if any) to use, I suggest you read both articles and make up your own mind. (I’ve previously read that there are risks associated with supplementing with Vit E beyond the advised daily requirement of around 80iu, and most Supplements seem to start at 200 to 400 iu, though I did find one at 100iu).
Note, don’t entirely rely on ‘Data Recency’, as often earlier data is proven to be more valid. Instead, consider the quality, source and ‘numbers’ presented by the data.