------------
"It is accepted fact that the underlying cause of Alzheimers is long term exposure to oxidative stress (free radicals)."
--------------
Then challenge your own statement, Google "the underlying cause of Alzheimer's"
I made it to page 3 without seeing the word "oxidative" one single time in the titles or excerpts. I saw quite a few other theories though.
Perhaps the answer lies in a ~20 year old drug who's patent protection for Alzheimer's expired while it sat on the shelf. It's possible, anything is possible, probable is another story though.