There's (Not Enough) Something In The Water

There's a piece in today's NY Times about Lithium, the chemical element that has been prescribed for certain types of depression for years. It seems that Lithium is in fact present in nature, by no means abundantly, but in trace amounts that might in fact have some small affect via drinking water... 

Most interesting was this, from the comments section:

I can't speak to the benefits of taking lithium, but I can relay a story related to drinking lithium water. There's a hot springs in New Mexico that has a lithium spring. The entire hot springs is devoted to relaxation and increased calm, so I can't speak specifically to the effects of lithium water and its ability to lower one's level of anxiety or depression. However, I can speak to the effects that it had on the vividness of one's dreams ... and this was an effect that all of my family members reported ... we had the most incredibly vivid and realistic dreams when drinking the lithium water. When the lithium water was not available, no vivid dreams. When it was available, vivid dreams occurred.

This too:

7-Up was originally called Bib-Label Lithiated Lemon-Lime Soda and contained lithium citrate right up until 1950. In fact, it’s been suggested that the 7 in 7-Up refers to the atomic mass of the lithium.

When I checked, the atomic mass of lithium is in fact 6.94, which might be rounded up to 7, but do chemists routinely work with averaged numbers and inexact figures? Probably not.