My dad is 65, seems more like middle aged now than 60's used to.
His dad died at 59 when I was little, and pictures of him show what looks to me like a man in his 80's or 90's. But then they lived very different lives, after WW2 my grandad was a prize fighter, strongman, turned alcoholic chain smoker and gambling addict, and died riddled with cancer. Also, he had been bald from the age of 21, so always looked older than he was, whereas dad still has his hair.
Although my dad has worked hard in a manual trade all his life, he only drinks moderately and never smoked). Physically and mentally he's doing very well, facially lots of sun damage as he still surfs regularly as well as trains a kids surf life saving club.