I would encourage anyone wishing to maintain a youthful appearance to begin to learn about dietary nutrition. (not talking fad diets....but proper nutrition by food selections)

You may also want to supplement your meals with quality vitamin & mineral pills. These will vary between men and women
as well as age groups. Your library & the internet is full of resources for learning about this.

Avoiding caffeine, nicotine, excessive amounts of sugar, salt and fats is a good start at avoiding premature aging.

But one has to choose whether they want a SO who is older in looks but thinks much younger or vice versa.

As for a healthful diet way of thinking, read "Unsafe at any Meal" by Dr. Renee J. Dufault.