daughter have learned that fluoride causes depression for them. This was learned through spiritual promptings and is not fully accepted by the medical and dental communities but when they use non-fluoride toothpaste and drink un-fluoridated water it makes a big difference. Studies are starting to look at the connection but still not generally accepted. Some bottled water is un-fluoridated and you can get water filters that filter out fluoride.

My wife notices the affects within a day if we are on vacation and she drinks fluoridated water.

This isn't the solve all solution for the struggle with depression, but hopefully it can help.