Prof Kesavan, the former Director of the Biosciences Group of the Bhabha Atomic Research Centre (BARC), has reported in his paper, to be published soon in a prestigious international scientific journal, that when mice were injected with a radiation dose of 7.5 gray, they died within 25 days. "When I injected them with caffeine (at the rate of 80 mg per kilogram weight of the subject under study) within 30 minutes of the radiation dose, they lived for 90 days," Kesavan told The Indian Express. He also found that nicotine-stained lungs survived better in a smoker who is also a coffee drinker. "Caffeine dilutes the effects of nicotine," says Kesavan.

The prestigious, high impact index Journal of Radiation Protection will publish the findings of Kesavanrelating to protection offered by caffeine from radiation, shortly. More than 25 years ago, another prestigious journal, International Journal for Radiation Biology had rejected Kesavan's paper for lack of sufficient supporting material to his theory that radiation-exposed mice when injected with caffeine lived longer. Subsequently, however, the journal inducted him into its editorial board and also published 50 of his papers on the subject.

It was by sheer accident that he discovered that caffeine, widely believed to be an inhibitor of the restorative or repair process was a "tremendous radio protector".

In the early 1970s, a research student, under Kesavan's guidance, found to her dismay that caffeine, when administered with cobalt 60 gamma rays showed reduced `damages'. This was contrary to the established theory that caffeine causes immense damage. "The student, wondering whether something was wrong with the Indian coffee, got samples of caffeine from all over the world and conducted theexperiment. But the result was the same - caffeine gave protection," says Kesavan.

The disappointed student dumped her papers. Kesavan salvaged them and began his own experiment. In 1972, he, along with his students, authored the paper titled `Radio protection by caffeine' for publication in the International Journal for Radiation Biology

. However, it was rejected for want of more working hypothesis. Kesavan continued his experiments. His theory is based on simple logic. "The component A (nuclear radiation) is bad for C (a mouse in this instance) and B (caffeine) is also bad for C. When A and B collide, C is spared," says Kesavan, adding that the process occurred in a millionth of a second. Further tests only strengthened his `sparing' theory.

However, few labs around the world were equipped to conduct such fast kinetic experiment. Finally, on invitation, he conducted his experiment in a lab at the University of Texas in Austin in the US. Last year, he received a communication from theJournal that his paper on survival of mice would be published early this year.

When there is a nuclear explosion, all hospitals and superstructure would collapse. So the best prescription Kesavan offers is a steaming cup of coffee or the Japanese remedy of a handful of chlorophyll-rich algae and potassium iodine.