Indian scientists are now holding him in isolation in a hospital in Ahmedabad, Gurjarat, where he is being closely monitored by India’s Defence Research Organisation, who believe he may have a genuine quality which could help save lives.

So far, Mr Prahlad appears to be standing up to scrutiny. He has not eaten or drunk any fluids in six days, and similarly has not passed urine or a stool in that time. He remains fit and healthy and shows no sign of lethargy. Doctors will continue observing him for 15 days in which time they would expect to see some muscle wastage, serious dehydration, weight loss, and fatigue followed by organ failure.

It is common in India for Jains and Hindus to fast, sometimes for up to eight days, without any adverse affects, as part of their religious worship. Most humans cannot survive without food for 50 days. The longest hunger strike recorded is 74 days.

According to Dr Sudhir Shah, who examined him in 2003, he went without food or water for ten days in which urine appeared to be reabsorbed by his body after forming in his bladder. Doubts were expressed about his claim after his weight fell slightly at the end of the trial.

“The most surprising fact is that his kidneys produce urine in small amounts, but he does not pass urine, it simply disappears,” Professor Anil Gupta said.

Doctor Sudhir Shah said the study could “help in working out strategies for survival during natural calamities, extreme stressful conditions and extra-terrestrial explorations like future missions to the Moon and the Mars.

Mr Jani, who claims to have left home aged seven and lived as a wandering sadhu or holy man in Rajasthan, is regarded as a “breatharian” who can live on a “spiritual life-force” alone. He believes he is sustained by a goddess who pours an ‘elixir’ through a hole in his palate. His claims have been supported by an Indian doctor who specialises in studies of people who claim supernatural abilities, but he has also been dismissed by others as a “village fraud.”

India’s Defence Research Development Organisation, whose scientists develop drone aircraft, intercontinental ballistic missiles and new types of bombs. They believe Mr Prahlad could teach them to help soldiers survive longer without food, or disaster victims to hang on until help arrives.

“If his claims are verified, it will be a breakthrough in medical science,” said Dr G Ilavazhagan, Director of the Defence Institute of Physiology & Allied Sciences.

“We will be able to help save human lives during natural disasters, high altitude, sea journeys and other natural and human extremities. We can educate people about the survival techniques in adverse conditions with little food and water or nothing at all.”

Not all scientists are curious about Jani’s strange capability. Some have dismissed Jani as a fraud.