The connection to the therapeutic effects of reduced heavy metal body burden with drinking coffee regularly wasn't made, but I found this pretty interesting:
A water filter made out of coffee grounds filters almost all heavy metals out of water within 30 hours:
http://www.nytimes.com/2016/09/24/science/coffee-grounds-filter-heavy-metals-water.html?_r=0
A water filter made out of coffee grounds filters almost all heavy metals out of water within 30 hours:
It turns out, coffee is made of chemical components that are really good at trapping heavy metals like mercury and lead, which are common water pollutants, and poisonous in high or sustained doses. Previously, other researchers used coffee as a powder to remove lead from drinking water, but getting the powder out afterward wasn’t easy.
By integrating coffee powder into a foam, Dr. Fragouli’s team is offering a possible solution, although the method has yet to be perfected for everyday, practical uses.
[...] They dropped their little foam block in water containing lead and mercury and measured the metallic concentrations over time. For a water sample with metallic concentrations of 16 parts per million (which are 1,000 times greater than what the Environmental Protection Agency considers a threatin drinking water), a piece of foam the size of a postage stamp removed 99 percent of the metals from the water within 30 hours.
http://www.nytimes.com/2016/09/24/science/coffee-grounds-filter-heavy-metals-water.html?_r=0