Deuterium and engineered longevity are in the popular press again:
[The method] centres on fortifying the body's tissues and cells against attack and decay caused by free radicals, dangerous chemicals produced when food is turned into energy. Such 'attacks' on proteins are particularly damaging and have been linked to cancer, Alzheimer's and Parkinson's.
Dr Shchepinov's theory is based on deuterium, a naturally-occurring isotope, or form of hydrogen, that strengthens the bonds in between and around the body's cells, making them less vulnerable to attack.
He found that water enriched with deuterium, which is twice as heavy as normal hydrogen, extends the lifespan of worms by 10 per cent. And fruitflies fed the 'water of life' lived up to 30 per cent longer.
Heavy water is toxic to mammals at very high concentrations, and as I mentioned in response to a paper from Rejuvenation Research in 2007:
Shchepinov argues that isotopes would only be incorporated in the sites that need to be protected from oxidation. 'Ideally, they will slow down the oxidation reaction so much that they will never be released to take part in other reactions. If some of them do break free, they will only occur in small concentrations,' he said.
As for the other folk quoted in [a science press article at the time], I'm dubious - it seems to me that the level of technology required to target the isotopes reliably (and keep them targeted) would enable far more effective methdologies of repairing rather than preventing oxidative damage.
I suspect that the main benefit to come out of this research will be an increased understanding of free radical biochemistry and its interaction with degenerative aging.
UPDATE 11/27/2008: You'll find a much better article on this research at the New Scientist.