Man claims to have had no food or drink for 70 years

Prahlad Jani is being held in isolation in a hospital in Ahmedabad, Gurjarat, where he is being closely monitored by India's defence research organization, who believe he may have a genuine quality which could help save lives.
He has now spent six days without food or water under strict observation and doctors say his body has not yet shown any adverse effects from hunger or dehydration.
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 specializes 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."
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.

He looks a little thin in the picture.

It's not only improbable, it's impossible. Most likely the guy was hallucinating that he has been without food or water for 70 years, due to not having ingested anything for a long while (starvation does cause hallucinations). The body starts to break down under extended periods with no intake of of nutrients and organs will completely shut down with no water.

I went 28 days without eating any solid food, I did of course drink water and a mixture of water,fresh squeezed lemon or lime juice, a table spoon of maple syrup and a bit of cayenne pepper a few times a day. The first few days I suffered from hunger, but the pangs dissipated and the next three weeks were fine. I lost a lot of weight, some muscle mass as well, but my body needed to be replenished in some fashion even if it was the bare minimum of nutrients. Not eating or drinking for years... seems a bit silly.