Already deprived of sunlight, fresh air and their loved ones for 26 days, NASA doctors say 33 miners trapped deep in a Chilean mine must continue to forego two other pleasures: alcohol and cigarettes.

Facing a wait of around two to four months as rescuers race to drill a narrow shaft 2,300 feet (700 metres) vertically down to extract them, the miners are in good spirits, and included wine on a wish-list of items to be sent down a tiny borehole from the surface.

Health officials have sent them high-protein, high-calorie foods in narrow plastic tubes to help them build up their strength after losing an estimated 22 lb (10 kg) each during 17 days entombed after a cave-in before they were found alive.

Booze will have to wait.

From the alcohol standpoint, we need to first get their nutrition up before we make any considerations there, said James Michael Duncan, NASA's deputy chief doctor, who flew with a team of medical experts to Chile to help advise the government on one of the world's most challenging rescue bids.

Some of the men have also asked for cigarettes, and health officials have sent them nicotine patches and gum.

It's an environment that's pretty enclosed and we don't want to contribute to any of the problems within the atmosphere of the mine, Duncan added.

Used to managing prolonged periods in confined areas on space missions, NASA is also advising the government on how to keep the men mentally fit for the weeks ahead.

Health Minister Jaime Manalich says the men are holding up remarkably well in the hot, humid tunnel. But they face a long haul.

Rescuers began drilling the escape shaft on Monday night, and by early Tuesday evening, had bored down 26 feet (8 meters) -- around 1 percent of the target depth.

MINE OWNERS TESTIFY

Dramatic video footage taken by the men last week with a camera sent down the grapefruit-sized borehole serving as their lifeline to the outside world, showed them bearded, their torsos bare to cope with the heat. Some were visibly thin.

The men have designated areas for sleep and card games while freeing space to keep items like toothpaste and deodorant. The men have also asked for laxatives to help regulate their digestive systems after initially surviving on two mouthfuls of canned tuna and half a glass of milk every 48 hours until supplies ran out.

Rescuers have sent them miniature projectors so they can watch video clips of soccer greats Pele and Maradona, and have also sent cards, dominoes and letters from their family members.

The owners of the San Jose mine testified before an investigatory commission of lawmakers on Tuesday, defending their company against accusations they had skimped on safety.

President Sebastian Pinera has vowed to punish any lapses, has fired officials of Chile's mining regulator and has pledged a major overhaul of the agency and safety regulations in light of the accident.

(Editing by Simon Gardner and Eric Beech)

NASA