According to the myth of Atlantis, the wisest people there found a way to live as long as they wanted. Most choosing to end it after 1000 years if I remember correctly.

Now, we know that this is a biological possibility regards to telomerase. In animal models they have already expanded life (health) span in animals by 11 times. In a human, this meens 800 years long life.

In the bible you can also read about some people living to I think more than 900 years.

Could it be some truth to it? :)