Not a Pill
My Internet meanderings brought me to a website entitled "LONGEVITYPILL.COM" yesterday, and I rolled my eyes. The author, Bill Sardi, seems an earnest enough fellow - he supports calorie restriction, for example - but the thrust of the website is very much more of the same old school of pills and drugs.
I'm going to go out on a limb here and say that when radical life extension technology - medicine that can add decades to our healthy life spans - is developed, it won't be in the form of a pill.
Sure, there are plenty of people working on drugs that might have quite significant effects on life span and health - but the majority of this work is simply not going to result in products that make as big a difference as we'd all like. Barring bad luck or bad genes, people can make it to a healthy 80 or 100 years through calorie restriction and a good lifestyle. It seems unlikely that any drug I'm aware of in the pipeline at the moment will do much better than that.
In any case, most of these near future products would have to be injected to have the desired effect. The human digestive system is very good at breaking down complex compounds - especially those relating to human biochemistry - before they get anywhere near the bloodstream.
The more complex therapies of the future are the sort of things you undergo in a hospital setting. Stem cell transplants, gene therapies, organ regrowth, cancer scans - these are some the technologies that will - we hope - soon extend the healthy human life span. One day, with the aid of advanced nanotechnology, we will no doubt be able to stuff these procedures into a pill if we so desired - but that day is a long way off. Those people chasing longevity pills and exotic life-extending drugs in the here and now are just barking up the wrong tree and putting their dollars into the wrong field of research in my opinion.