The recent craze for human breast milk amongst certain fitness communities, fetishists and chronic disease sufferers is ill advised say the authors of an editorial published by the Journal of the Royal Society of Medicine. There is a lucrative online market for adult buyers of human breast milk, with websites and forums describing it as a 'clean' super food that can lead to gains in the gym, and even help with erectile dysfunction and cancer. There are claims that it is more digestible and contains positive immune building properties. The authors, led by Dr Sarah Steele, of the Global Health and Policy Unit, Queen Mary University of London, write that these purported benefits do not stand up clinically and raw human milk purchased online or in an unpasteurised state poses many risks.

"Nutritionally there is less protein in breast milk than other milks like cow's milk," said Dr Steele. She and her colleagues write that the benefits of breast milk are being found in the lab, not in drinking a bottle ordered online. "Potential buyers should be made aware that no scientific study evidences that direct adult consumption of human milk for medicinal properties offers anything more than a placebo effect, said Dr Steele. The authors warn that human milk is potentially very hazardous if used to replace a healthy balanced diet.

Failure of women to sanitise properly when expressing milk, the failure to sterilise equipment properly, and the improper or prolonged storage and transportation of milk can expose consumers to bacterial food-borne illnesses like any other raw milk.

The lack of pasteurisation and testing not only indicates a bacterial risk but also exposes consumers to a host of infectious diseases, including hepatitis, HIV and syphilis. "While many online mums claim they have been tested for viruses during pregnancy, many do not realise that serological screening needs to be undertaken regularly," said Dr Steele. "Sexual and other activities in the postpartum period may expose the woman expressing to viruses that they may unwittingly pass on to consumers of the milk."

The authors call for health professionals and regulators to issue public guidance against the purchasing of human milk from Internet sources for adult as well as infant feeding.