It's a matter of perspective, at least in part, but dedicate yourself to a few simple steps and you may find more than a few tongues wagging over you. If you want to live a ridiculously long life, it seems to be just common sense that you should make at least a little effort to take care of yourself. The other element I've been thinking about is going to require you taking care of others.
No, my plan doesn't involve harvesting from others for replacement parts. I think the key may be in the dogs. They're all around us. There are so many millions of them. We anthropomorphize them all the time, and not without cause. Clearly, they have feelings and personalities all their own, making each one a unique individual. For our project, I'm focusing on the issue of intelligence. Those of us who've spent much time around dogs can probably attest to having known stupid dogs and surprisingly smart dogs.
Focusing on the surprisingly smart dogs, they understand when we talk to them and seem quite capable of communicating with each other. You want raise one of these dogs. Start when you're both young. I recommend a bigger breed that you'll only get eight or nine years out of and breed it when it's a few years old, maybe four or five. Now, assuming everybody's healthy, you can probably get a couple of good litters of pups.
Take your time getting rid of the puppies. They're adorable and good for your health. You should play with them and enjoy them. While you do that, try to figure out which are the smartest and how many you're going to keep to replace the first one when it dies. This is important because the parent is going to teach the children.
Over the next few decades, you're going to repeat this process with these dogs, maintaining an unbroken lineage. Through these generations, you could easily have produced a hundred dogs. All of them will have had direct contact with you (we're not counting the ones that have been produced by the pups who were adopted out, though even they may have been taught a little about you by their young parents).
The payoff is that, allowing for intelligent communication among your selectively bred canines, your role as caretaker will be known among these bright furballs stretching all the way back to that first dog you started with. Dog #1 will, of course, be long dead and many of its descendants will have followed it into the ground (probably helpful to keep as many graves as you can near each other) and you, having outlived them all, will be known as The Feeder Who Never Dies. Your legend will spread and perhaps they may even one day make the connection that others of the great Feeders are similarly undying.
It'll take time to tell for sure. And we'll have to learn to understand the dogs.
Well, one Mad Science Fair Project at a time.