User blog comment:Blackendedsoul/Kaido's devil fruit/@comment-10543621-20160120035200

I don't think his suicide hobby should be used as an indication of whether he has a fruit or not. Like others have said, I see his suicide hobby more of testing how much abuse he can take before he actually kicks the bucket, as opposed to actually wanting to die. I mean, someone that actually wants to die won't really become a Yonko just like that. Being a Yonko isn't just about being strong. You obviously need ambition, leadership abilities, etc. The whole commiting suicide thing is probably just a side hobby.

If anything, he could have eaten some kind of invincibility DF or a DF that makes him incredibly durable, and as such he's developed a hobby to test how much damage he can dish on himself and not die.