According to LiveScience, the headline is literally true.
Optimists in the study had HALF THE RISK of being taken off the list by death within a decade.
It’s well worth being optimistic. That’s the bottom line.
I also guess that intrinsically more relaxed and cheerful people use less crutches like inhaled cancer (’baccy), bottled liver meltdown (grog), industrial gut-widener (instant polystyrene with sauce — AKA junk-food) or social props (personal arguments and/or TV drama). That would all probably help.