How come patients diagnosed with Alzheimer's are not told about Folic Acid?

How come more doctor's are not telling their patients with the onset of Alzheimer's that taking a daily recommended allowance of folates; B vitamin nutrients(400mcg per day) can reduce the risk of Alzheimer's disease? This is just disgusting that our medical community will not heal their patients anymore.

Oh, I know what it is, Big Pharma is doing their best to 'buy off' doctors with no consience and really need to extra income. My sister used to be a drug rep and when she found out what was really going on, she had to, in good conscience, resign.

What is our world coming to when human life no longer matters?