That's not all they want young people for.

Aging is so multi-causal, that it will be decades before they can get treatments for one portion of what causes it (telemeres shortening) and even then there are other causes of aging. Youth pills are centuries away, if ever. We will all die, like everything that has ever lived before you. Get your soul right with God.

That said, we know one kind of cell line that is immortal, cancer cells, but they kill the host.

There's a makeup collection called "young blood". Your title made me think of that.

Like the Blood Boy episode of Silicon Valley