For example, there's an episode of The Mary Tyler Moore Show with Eric Braeden (https://www.youtube.com/watch?v=JUyxHgPHR-s). He would have been about 35 when it was filmed but could have easily passed for 15 years older.

https://dg31sz3gwrwan.cloudfront.net/screen/226102/1_iphone.jpg

https://cdn.dialogues.org/100555/external/57433a05e4b01e48b13caff3/dj2uxrh7y5_100555.jpg

More time outside in the summer due to a lack of air conditioning and no skin care products ? Look at pictures of baseball players before World War II...all day games.

Gavin Macleod was 39 when he started on the show and Ed Asner was 41. They looked way older than that.

Probably because of more beer and cigarettes, combined with a less vain culture back then.

Unrelated, but I never knew how Betty White looked without the gray hair until I saw YouTube uploads of the original CBS Password a few years ago. I think she actually looked better with the gray as opposed to being a brunette.