Thank you all for the responses, truly appreciate the insight.
I do realise that there is no way to have a job like this without it effecting our health negatively.
The idea is simply to try and minimise these "risks".
I quit smoking 1 year ago. When I realised how tired my body would be from all the flying, time differences, sleep deprivation, I concluded that I could not have an addiction that will further make things worse.
I've flown plenty of guys in their 50s, some early 60s that are very active, are very healthy, and look very young for their age, and it didnt surprise me that these were always the guys that didn't smoke, ate healthier, and tried hard to compensate for the tough work environment. And the opposite was also true with young and unhealthy guys.
A TRE I flew with many times during my training who realised that I am an athlete(who happens to be a professional athlete himself), was a guy that I picked up a lot of these habits from. As a young guy, I did not care about these things before he started speaking to me about them.
Just like I am now, he was always cautious of his habits, and watching and asking him/talking about how he dealt with it has taught me a lot.
He always(as much as possible) got his own meals, he would drink tons of water, minimal coffee as much as possible, he would use sunscreen to protect his skin from the ageing effects of radiation, and again it was really no surprise that he looked a good 10 years or so younger than his age.
I appreciate your comments a ton. It's always nice learning from others that have been in the same situation.
I understand that some guys have the mindset that this is a silly thing to worry about, but for the guys that do put an active effort to be extra cautious, its always nice to learn from likeminded guys.