<human>: Can you give me the gist of the text in a nutshell?

I'm 18 and I will soon be taking an online animation school. But until then, I don't have much to do with my life, so I've spent my time staying up late at night and drawing. I prefer working at night because of the lack of distractions.

Anyway, my Dad has been rather irritated with my sleep schedule. He's been telling me that in his experience, staying up at night and sleeping during the day was bad for his health and he blames his obesity on it. When I ask him what exactly is wrong with it, he simply tells me "It's unnatural." So I've decided to come here and ask if there are any health risks actually involved with mucking up my sleep schedule.
<bot>: My Dad is angry at me for staying up at night. Is there any health risks involved with having a twisted sleep schedule?