It depends on how one looks after there body.
NO alcohol ( or very little)
NO make up ( look at those chemicals that age you on those products..Formaldehyde?
Sleep patterns ( get at least 8 – 12 hours sleep ( real restful sleep to recharge the body).
Sometimes stress can cause early grey hair plus other aging effects.
DNA inherited also comes into play as well, so look at your mother/father,even grandparents aging stages….( however stress in some eras makes a difference and how one handles stress too).
Diet also a big factor.
My late mother looked younger and her skin was healthy because she NEVER Drank alcohol and never used makeup unless lipstick and light blush.
She had lots of stress in her life but she handled it well and remained positive so that made a difference. She had her husband ( my late father) as a good support sometimes.
Age isn’t the only factor of aging..all the above does.
The good news is that one can look after themselves better now and possibly slow down the aging process somewhat.
By the way age 50 years old is a “baby” when your older that that and many would love to look that age, now.