I have had a resurgence of some feelings of depression/anxiety in the last 6 months. I wasn't sure if it was perimenopause and hormonal so I went to the Doc. She upped my usual dose of Zoloft which works well on me but there was little change. Anyway....after a number I tests it was found I have a vitamin B12 deficiency. I did a "google" on B12 and found that neuropsychiatric like symptoms of depression/anxiety can be caused by lack of B12.  It was great to find the reason behind my symptoms. I will be getting B12 injections and watching my levels. B12 is found naturally in red meat and milk but if you have "tummy" troubles may not be absorbed. I also take omega 3 fish oils as they are recommended for depression ( and on the side they are helping the arthritis in my hands too...a bonus). Anyway, its not a bad idea to have your B12 levels checked and make sure your diet includes B12 rich foods.