The first step is to think about who you hang out with. There’s no silver bullet for longevity. I’m not gonna tell you to take a pill. If your three best friends are obese, there’s a good chance you will be. Surrounding yourself with people who don’t smoke or drink too much and who have a spiritual component in their lives has a profound impact over time. Cut out the toxic people in your life and spend time and effort augmenting your social circle with people who have the right values and a healthy lifestyle.

I don't know why, but this snippet brought Robert Greene's The 48 Rules of Power to mind: "Infection: Avoid the Unhappy and Unlucky" (Rule 10). Of course, Greene's approach can be interpreted as a tad Machiavellian. But the message is still the same: watch who you're hanging out with. I've noticed that many of one's peculiar behavioral habits can be directly attributed to friends and acquaintances. It's interesting to see longevity talked about in the context of the people you spend time with.