Honey kills antibiotic-resistant bugs
Honey could help to treat wounds that refuse to heal. Researchers seeking scientific support for honey's legendary medicinal properties have found that it stops bacteria from growing - even strains that are resistant to some antibiotics1.
Records of people covering wounds in honey stretch back to ancient Egypt. Until recently it was believed that honey's syrupy consistency kept air out of wounds, and that its high sugar content slowed bacterial growth. The new evidence suggests that honey must also have other properties that kill bacteria.
Compared with an artificial honey solution of the same thickness and sugar concentration, natural honey kills bacteria three times more effectively, Rose Cooper, a microbiologist at the University of Wales Institute, Cardiff, and colleagues have shown. They are not sure what the active ingredients are.
Some types of honey, when diluted, form hydrogen peroxide, which kills bacteria and can be used to clean wounds. But Cooper's team rules out the possibility that hydrogen peroxide is the only force at play.
Both pasture honey, which generates hydrogen peroxide, and manuka honey, which does not, stop bacteria from growing in the lab, they demonstrate. They used strains of Staphlyococcus and Enterococcus that can withstand 'last resort' antibiotics, such as methicillin and vancomycin. The microbes were collected from wounds and hospital surfaces.
Honey may be antimicrobial because of enzymes secreted by the bees that make it; alternatively, its activity could be due to its acidity or to chemicals from the original plant nectar, Cooper speculates. "It's a traditional remedy that has been overlooked," she says. "To reintroduce it, we must have evidence to support its antibacterial and healing properties."
Andrea Nelson, a nurse researcher who has worked on chronic wound healing at the University of York, UK, agrees. To convince sceptical doctors, clinical trials must be carried out applying honey to patients' wounds, she says.
Infected wounds cause pain, result in extra time in hospital, are costly to treat and can lead to complications and even death. Treating them has become a problem, as prolonged use of antibiotics can result in the emergence of resistant strains of bacteria.
For this reason, other alternative remedies are also being explored, says Nelson. These include iodine, silver-based compounds and 'larval therapy', in which maggots are applied to the wound to eat away dead tissue and break down bacteria.
While scientists continue to scratch their heads over honey's secrets, some companies are already making sterilized tubes of honey and honey-impregnated bandages for treating wounds.
Cooper is careful to add a warning: "We're not suggesting that anyone should rush out and buy honey in supermarkets to treat wounds." The heat-processing of store-bought honey would probably eliminate any antibacterial properties, she says - anyone with a stubborn wound should seek professional treatment.