I recommend: Unleash the Power of the Female Brain, by Dr. Daniel Amen. You may have seen Dr. Amen on PBS, talking about his SPECT scans and mental health.
My husband bought me this book for me, and I really love it–I have the book all marked up (not that I have done it all!). This book discusses optimizing your health, and gives many practical steps. It talks about diet, supplements, exercise, different brain types, and hormones. It is very informative, and I think you will enjoy it!