Transhumantists’ Delight: A Pill to Extend Life?

As President Obama tub thumps about cutting medical costs and old people are being targeted for rationing, some scientists are trying to find a magic pill to extend our lives.  And now, they may have found a candidate. From the story:

Rapamycin, a drug commonly used in humans to prevent transplanted organs from being rejected, has been found to extend the lives of mice by up to 14% — even when given to the mice late in life. In flies and worms, drug treatments have been shown to prolong lifespan, but until now, the only robust way to extend life in mammals has been to heavily restrict diet.

Wait a minute, a recent study found that chubby people actually live longer! But I digress:

Immune suppressant drugs can be dangerous. What about that?

The big question, of course, is whether this drug could extend human life. Both Harrison and Kaeberlein are cautious. “I wouldn’t do it myself and wouldn’t encourage anyone to do it at this point,” says Harrison.

Getting the dose correct is another problem. A normal human dose of rapamycin is between 2 and 5 milligrams per day, much lower than the dose given to the mice, which was 2.24 milligrams per kilogram of body weight per day. Perhaps rapamycin could be altered somehow, to reduce its effects in the immune system while keeping its anti-ageing effects? “It’s an open question whether you can uncouple that from immune suppression,” Kaeberlein says. But in future, he says, it’s likely that it will be possible to tweak rapamycin in this way, or to target the other molecules in the pathway instead. Kaeberlein’s lab is already working on these downstream targets.

That sounds very complicated and expensive.  Besides,  just because the pill allowed us to live longer, that doesn’t mean we would live healthier. Moreover, don’t we have more important priorities for our limited science research dollars?  It seems to me that we would be better off focusing on healthy life styles and striving to get the most out of the time we have than tilting at the windmill of radical life extension.