Stress definitely ages a person. If you know how to manage stress, or don’t put yourself in a situation where you experience much of it, then you certainly won’t age as quickly.
You’ll also age faster if you don’t look after your health properly, and you also don’t handle stress well if your health is poor.
And then there’s people with children. The added stress of having a family ages people faster as well. Perhaps due to sleep deprivation and less time to look after your health.
All of these things age people faster but the common connection is how well you look after your health.