Ten hours after your last insulin response your body starts producing human growth hormone, adrenaline and testosterone to burn fat.
Testosterone is also the hormone responsible for wanting sexy time.
Edit: https://imgur.com/92Zs7fn
Human growth hormone production does increase in a fasted state.
Bodybuiilders say that its good to train fasted because protein sythesis is heightened.
By all means though, if you can get some I say go for it.
Wow, I thought it was just me. I started 16:8 about a month ago. This week I did 20:4 for a couple of days and noticed the horny taking over. I need to find more resources because a YouTuber I follow said testosterone drops when fasting.