Regarding mental illness: A friend has been "battling" depression for over a year, she gets a bit better and then backtracks. Her meds have gone up over the last year from 112 to 300 dosage.
Guess what: She had a physical. All was well except that she had a serious shortage of vitamin B12. Won't go into details, but an IMPORTANT vitamin, and shortage is usually due to malabsorption.
So the Doctor told her to take 2000mcg of B12 a day, and after ONLY 3 days, she phoned and told me "she feels" like a new women.
Today she even laughed. She was in the livingroom, her daughter and husband came in and asked her: Was that you laughing, and she said yes. They all hugged..... She went for a long walk, and feels better, a lot better. The insominia is gone, the fatigue, the weakness, the focus and concentration is better, she "feels" lifted and energized.
Yes, this lack of vitamin can mimic depression, and it take years before it finally "gets serious", but can cause permanent damage.
I am VERY, happy for her and her family is glad to "have her back".
Amazing, yes, but a true story.
She may still have depression, who knows, but I do know that the lack of this vitamin may have made her feel "depressed" when it was the vitamin that was responsible for a lot of the symptoms.