I am a member of ImmInst.org, Immortality Institute, and sponsor the supplement forum there. This is a professional, high integrity organization that is worthy of of a look-see, and if you like what you discover, support the cause, become a full member. They offer a neat introductory package once you sign up.
You will be pleasantly surprised to discover it is hype-free, and quite scientific in its approach to the subject. Ever really considered the implications, nay, the possibility of living beyond the norm? Fascinating stuff and I promise you it will change your life.
It changed mine.