Basically, what it says in the title. I've never trained in any martial arts, except some mandatory basic H2H training in the military over 10 years ago. I'm 197 cm tall, and weighting at about 100 kg, not super muscular, but not a total slouch either. Generally, i'm considering it as something that would improve my physique, and as an effective self-defence tool. I'm not into it for the competitive side, since that ship is probably sailed looooong ago. Is it too late to pick it up now?
There was a news report I remember seeing a few months ago about 40 year old and older boxers still having bouts. So, unless you have some unmentioned medical problems I don't see any issues.