system
Given the following post, respond as if you're commenting on Reddit:
human
When washing by hand, does washing dishes with hot water kill more germs than washing with cool water?

My mom always told me to wash the dishes with hot water because it would kill more germs. This never made sense to me because I always thought that your avg germs died at a temp at or above 140 which I believe is just to hot for human hands to wash dishes. Moreover I thought that providing a warm environment would just make it easier for them to breed.

So I guess this is a two part question. 

1 Does hand washing dishes with hot water kill more germs than with cold water? For a standard let's call hot water 140 degrees F or 60 degrees C. That should be about the hottest most people can stand right? If not then feel free to change this.

2 Since we know that generally speaking the colder it gets germs tend to reproduce. Or seen another way at what temp. do germs stop reproducing or at the very least at what temp do germs start to reproduce less.
gpt
Microbiologist here.  Correct, most will not die unless it is so hot it will hurt your hands (unless they are soaked in it for a long enough time).  However, hot water will flush away oils much better and most soaps will dissolve best and work best in hot water.  The key is really to flush the bacteria away from your dishes, not kill them and leave them in place.  Cleaning is the key, not disinfection.  And to maximize cleaning, use hot water.