The Science Behind Honey on Wounds
Honey has been used on and in wounds for centuries and just neglected a bit by modern medicine until rigorous work by Dr. Bernard Descottes of Limoges, France and Dr. Peter Molan of Wakaito University, Hamilton, New Zealand showed in in vitro and clinical studies its remarkable properties.
Wikipedia’s entry on honey remains my preferred up to date source of information on honey’s mechanisms of action in a wound. How and when the first man decided to place honey on a wound must have been long ago, motivated more by its availability and proverbial stickiness, not by any understanding of the array of mechanisms by which we now understand it to promote healing. Bees produce honey as an energy storage vehicle and therefore invest it with the capacity to preserve itself from degradation by microbes. But likely they also made it over the course of evolution into a healing substance for the bees themselves, inside and out.
Honey closes a variety of human wounds faster than any dressing substance I have witnessed in 30 years of medical practice. Its mechanisms for doing so fall into two categories: antimicrobial activity and promotion of healing activity native to human tissue.
Honey inhibits bacterial and fungal growth due to its high osmotic quality– inherent in a gel which is over 80% fructose and glucose. It’s bee enzyme Glucose oxidase produces small quantities of hydrogen peroxide when tissue fluids contact the gel. Hydrogen peroxide is toxic to most bacteria and yeasts. Honey contains floral nectars which may have antibiotic effects, the most studied being Unique Manuka Factor (UMF), now understood to be Methylglyoxal of New Zealand’s Manuka Honey. Honey also contains primitive antibodies called Antimicrobial Proteins (AMPs) which live in many living things and are capable of immediately punching holes in cell membranes of microbes but not animal cells. Honey inhibits growth of “superbugs” such as methicilllin resistant Staphylococcus aureus (MRSA) of both hospital and community origins which are increasingly menace patients in the developed world by outsmarting clinical use of antibiotics.
We are learning that bacteria create toxic biofilms to resist penetration by cellular, humoral and antibiotic defenses. Honey is the biofilm that gets there first by being so sticky. Honey sucks interstitial fluid out of wounds which forces bacteria to have to swim upstream against the body’s soluble defenses such as complement and antibodies.
Promotion of Healing
Honey helps wounds heal in so many different ways that it suggests a long co- evolution with man for this use, or if you prefer, the Intelligent Design of a supreme being. Either explanation fills even a dispassionate science nerd with awe. Honey creates a biofilm which is a good thermal insulator and prevents cooling and drying of tissue, both destructive factors. Without drying going on, no scab formation takes place. Scabs, which are formed from dried serum proteins, are good temporary protectors of an open wound but often delay final healing and seem to play a part in disfiguring scarring. Hugh Laurie’s TV character Dr. House is fond of pointing out that “patients lie” but I would counter with my observation that they more often pick at scabs, by intention or not. And medically trained nurses and doctors are the worst offenders who pick at their own scabs those of others. So a wound dressing which bypasses this phase would cut wound healing time by one third which is just whaty we observe clinically. Honey osmotically sucks fluid out of wounds which not only make bacteria have to swim upstream, but it decreases swelling in viable tissue which encourages capillary blood flow. Honey and tissue fluid produce hydrogen peroxide which in addition to being toxic to bacteria also is “chemotactic” to wound healing elements: lymphocytes, fibroblasts, and new blood vessels. So honey promotes “angiogenesis” of new capillary loops whose little red granules we can observe in healing wounds giving it the name of “granulation tissue.” Surgeon- trainees learn by example from their senior mentors to purr with pleasure at the appearance of “excellent granulation tissue” on rounds as well they might since it portends “a good result” (live discharge.) Honey is mildly acid and this is corellated with more rapid wound healing. The Dublin, Ireland Wound unit in our reference section correllate the speed of wound closure with low pH in their bedside meters. When the pH climbs, it is time to add more honey. Finally, “it has not escaped our notice,” to borrow the false modesty of Watson and Crick, that glucose contained in honey directly feeds the fibroblast which obligingly lays down collagen in the wound matrix faster.
“Health Care Reform”
Wounds dressed with honey require fewer dressing changes which reduces cost, patient discomfort and inconvenience. I routinely leave honey dressings for 3-4 days which would have earned me (even more) reprimands in 1979 as a medical student at Columbia P&S using daily saline gauze “wet to dry” debriding dressings on my surgical rotation. Honey dressings almost never permit a wound to fester and therefore need be changed only if, wet, soiled or loose. Every dressing change is a chance to contaminate the wound and disrupt the fragile wound matrix setting back the patient’s schedule of healing. Paradoxically, diabetic wounds are especially well-handled with honey as I have observed although the fearful patient needs the reassurance of my grey hair and serious face to ward off the notion of hippie quackery. Odors in a wound are ordinarily a sign of sulfide-producing bacteria. Honey eliminates odor so that patient even with large wounds are more likely to be unashamed and socially active. That patient has, instantly, a better quality of life less tendency to depression and a better chance to heal. Medihoney(TM of Derma Sciences, Toronto) is the product which is FDA-approved for use in US hospitals–made from New Zealand manuka Honey. Insist on it if you or a family member have an open wound– pricey about $15/oz. For scrapes, roadburn, impetigo use our home-made mixture made from local honey in preference to triple antibiotic ointment, bacitracin, mupirocin (bactroban) or neomycin. These traditional antibiotic mixture sensitize skin and are toxic to wound healing elements as well as to the bacteria and end up retarding progress. I arrived at my mixture of honey with aquaphor at the suggestion of a fellow beekeeper to solve the problem of honey tending to run at body temperature. The petroleum jelly with lanolin added for emulsification keeps the honey from absorbing moisture from the air. This cheap and readily available mixture has been a tremendous satisfaction to me and my patients for 4 years. I give you “health care reform at $1.25/ oz!”
Press the “Make your own” icon on the tool bar of the website and follow instructions.
Take “before and after” pictures with clinical and timeline information and send them to firstname.lastname@example.org. I will post them and we will build the “youtube of wound care” together.
Dr. Allen Dennison, Internal Medicine, Medical Director, Evergreen House Health Center, Life Care Centers of America, East Providence, RI