I dunno about living forever, especially by magnets (crapola if u ask me), but the human aging process can be slowed considerably. Your genes are like shoe laces: they have a 'plastic' piece on the end holding the strands together. Every time your cells divide to replace dead ones, the ends shorten. When they are gone, the cell dies off. Scientists have figgered out a way to prevent the ends from ever shortening, extending your lifetime considerably. Initial testing with fruitflys and some small animals indicate that the average lifespan can be tripled. So the average human lifespan, not counting 'unnatural deaths', could be as high as 300 years on a VERY good diet and exercise regiem.
Extending human life traditionally has one major problem: population. If everyone on earth lived three times longer, the world population would triple very quickly since old ppl wouldn't die to make room for new ppl. Then ppl start starving to death like in poor african countries where we provide medicine but not food. Until science has advanced to where we can support many many more people, we shouldn't concentrate to much on extending life, and more on making room for new arrivals or limiting the birthrates to accomodate. Personally, I thing planetary colonization is the answer, so see ya on mars!
P.S. Sorry about the rant, but I hope it was at least informative 
