Dogs can do some really amazing things, and this is one of them!
From BBC Earth:
Dogs watch us all the time and read our body language like a sixth sense. They also smell our bodies for changes.
Max smelt cancer in Maureen before any medical scans could pick it up. Dogs do this naturally and can be trained to pick up on tiny volatile chemicals given off by cancerous tumors. They can even be taught to alert diabetics to low blood sugar levels.
Check out this short (4 minute) video…
Source: BBC Earth
Check out BBC Earth on BBC online – http://www.bbc.com/earth/world