Is there any way to permanently change the font of your outgoing email messages?

You know how when you type an email and if you don't touch anything on the toolbar the font is always the same, boring arial size 10? is there anyway to change that to arial size something else?Is there any way to permanently change the font of your outgoing email messages?
Most of the email programs have tools that will allow you to set default settings the way you want it. Fonts, font size, font color, script. It depends on the program. You need to be specific as to which program you are using.Is there any way to permanently change the font of your outgoing email messages?
At least not in my knowledge