It is an undisputed fact that for the vast majority of newborn babies, breast is best. Less of an orthodoxy is the credence that human milk - with its unique composition of nutrients, enzymes, growth factors, hormones and immunological and anti-inflammatory properties - can be used to cure not just the lion's share of everyday ailments but some serious illnesses too.

If the biggest breast believers are to be taken seriously, everything from conjunctivitis and sore throats to cold sores and tooth decay can be relieved with a healthy squirt of mother's milk.

Spotty teens are constantly searching for a miracle acne cure, but it remains to be seen how many would swap their Clearasil for lacteal fluid if it meant an end to their battle with the blemishes. Yet there are those who firmly believe that wiping one's face with a cotton pad daubed in breast milk is a surefire way to clearer skin.

Now it has been revealed that adult cancer patients in America have been glugging breast milk in an attempt to boost their immune systems and reduce the side-effects of chemotherapy. A milk bank in California has supplied 28 adults in the past four years with donated breast milk. Patients armed with a prescription from their GP have been supplied the nutritious liquid - primarily meant for premature and low-birth-rate babies - by the Mothers' Milk Bank in San Jose.

According to the Sunday Telegraph, one recipient, a computer consultant called Howard Cohen, claimed his rather sickly-sounding twice-weekly "smoothies" made with the bank's milk had helped put his prostate cancer into remission.

But contrary to the large amount of publicity generated by the Californian milk bank's admission, there has been very little research conducted internationally into the curative properties of breast milk for poorly adults.

The most famous ongoing study has taken place at Lund University in Sweden. A team there reported last year in the New England Journal of Medicine that a compound found in breast milk had the power to destroy many skin warts, raising hopes that it might also prove effective against cervical cancer and other lethal diseases caused by the same virus.

Dr Catharina Svanborg, professor of clinical immunology at Lund, claimed that if the breast milk compound - since named Hamlet - proved successful against serious diseases, it could probably be synthesised in the lab instead of being extracted from the milk. If proved correct, this would represent a major scientific breakthrough. Replication of the unique composition of human milk would surely pique the interest of pharmaceutical companies, and perhaps turn breast milk into a commodity.

This would be a very important development. There are only 17 milk banks in the UK (and just six in the the US), and while officials claim that there is no national shortage as such, there is very rarely a surplus of milk.

Gillian Weaver, chair of the United Kingdom Association of Milk Banking (UKAMB), says: "UKAMB would welcome any research into the potential beneficial uses of donor breast milk. However, we feel it is more imperative to establish an evidence base for the uses of donor milk for premature and sick babies as this is the group for whom the donated milk is intended."

The Guardian understands that requests have occasionally been lodged with the UKAMB for milk from adult cancer sufferers who have read about the Swedish report. Such requests are routinely denied. There are also concerns that potential donors might be put off by the American example if they weren't sure that their milk was going towards babies.

Professor Lawrence Young, director of the Cancer Research UK Institute at Birmingham University, is sceptical about reports that breast milk can alleviate the suffering of cancer patients, and believes that such reports can raise the hopes of vulnerable people by making them believe that this one thing is going to cure their illness.

"Until it is scientifically proven in placebo trials, I would not take any research seriously," he says. "But if a patient of mine came to me saying he or she was going to take breast milk, I wouldn't have a problem with it - as long as they were not doing it at the expense of conventional therapy."

And what of those old wives' claims that breast milk can clear skin complaints from chapped lips to unsightly acne? A call to a dermatologist at one of the UK's foremost educational establishments is met with derision. "Ha ha ha ha," he says. "Breast milk, you say? I've never heard anything of the sort."