I have a diabetes alert dog. We trained each other. So this article: http://gizmodo.com/we-finally-know-how-dogs-sniff-out-diabetes-1782670434 says that scientists have finally figured out what the dogs are detecting.
She’s been helping me for years and after being without her for a week, I know even more what is going on.
Yes, she detects the lows, but she also PREVENTS them. She learned to figure how just how much exertion and how much food I’ve eaten goes together and she’ll modify my behavior so that I don’t go low.
Weird, yes, but it works for us.
My next experiment in this realm is to train the next dog.