Judo isn't that healthy either. Many Judo-ka have hurt their backs from the damage accumulated from falls and there are other ways to injure yourself in Judo. If you're looking for those sorts of high stress combat situations you can get that with Karate styles that practice a lot less contact. There's still high pressure but a lot less than full contact fighting where you're just hitting and getting hit all the time. Some chance of injury but it's a lot rarer.

I do agree that getting constantly hit in the head is probably not a good idea (e.g. boxing). If you want the stress of public speaking join Toastmasters or something ;)