I am around 30 and at least still I feel same as 20. Although I try to walk at least 30 min per day but the city I live in Asia is really shit for walking so it ends up being through shopping malls or some park.

Also I have been taking metformin (daily) and rapamycin (weekly) since like age 24 not sure they have helped but it's easy to buy here so I am giving it a try. I also use sunscreen if I go out during the midday which I rarely do in the tropics..