Lack of Iron and dementia in the elderly

I know that iron can be harsh on the stomach and that is why many elderly do not eat iron rich foods, but we need iron to think , to live. So if an elderly is having signs of dementia check out the diet, most of their diets are bland and lack iron..  have their blood checked by the doc to make sure..always.
I almost died from anemia so I have some insight to what the lack of iron can do to your physical presence and the mind.  In order for the brain to utilize O2 it is carried on the FE molecule,,oxygen and iron, have a unique relationship. No iron, no o2 to the brain.. things don't work right.
Anyway like I said,, first hand knowledge,,came close but no cigar.