I only torrent video, audio and epub files. For those as long as your player is up to date you should be fine, nobody is going to burn a 0day on you.
Now if you torrent executable files it is a different matter. Mac and Linux malwares exist, they are just a lot less common. You should try to find a trusted source, public trackers are not one. And you could restrict and monitor the program to see if it tries to do suspicious things. By running it in a sandbox like firejail or preventing it to access the internet with your firewall, you could use a tool like opensnitch to see where it tries to connect.