Miraculous Manuka

By Lynley Hargreaves 15/04/2015

Cliff Vann Eaton
Cliff Van Eaton

Manuka honey – which at one time beekeepers literally gave away – is now bringing such fantastic prices that plans are afoot to create large-scale manuka plantations, and young people around the country are taking up hives and veils. Beekeeping specialist Cliff Van Eaton – whose fascinating account of how manuka honey became a New Zealand icon is a finalist for the 2015 Royal Society of New Zealand Science Book Prize – and researcher Peter Molan, who first discovered the unique antibacterial properties of the honey, tell us more about the amazing rags-to-riches manuka story.

Do you have manuka honey on toast for breakfast?

Peter Molan
Peter Molan

Cliff: Thanks to the special properties Peter discovered in manuka honey, it has now become arguably the most expensive honey in the world. Honey that has been tested and found to have a low rating is still affordable as a table spread, but the honey with high levels of non-peroxide antibacterial activity is these days being used instead to treat wounds and burns in clinical settings around the world. As I show in the book, Peter was also instrumental in the development of manuka honey dressings.

Peter: Not on my toast, but I keep it in the house for medicinal purposes. The other day I picked up the wrong end of the soldering iron and got a bad burn, so I dashed in and smothered it in manuka honey. The pain went away quickly and it never even formed a blister.

How long has honey been used for healing?

Cliff: Archaeologists tell us that honey has been used as a medicine from the very earliest times, and I spend a full chapter in the book detailing some of the more interesting records of that use in both western and eastern civilisations. For our ancestors honey had what’s called a ‘magico-religious’ significance, particularly because unlike most other foods if it was kept in a covered container it wouldn’t spoil. This self-preserving aspect of honey relates directly to its ability to act as a potent natural antibiotic. The ‘miraculous’ nature of honey was obvious in ancient times, but it’s only more recently that we have begun to really understand the science behind it.

Peter: When I first started looking into it, there were some reports in the medical literature of honey healing wounds where nothing else was working. But different types of honey were just treated generically. Yet if you go back into ancient history the Greeks were very well aware that some honeys were better than others.

And there was – it turns out – some folk wisdom in New Zealand that manuka honey was particularly good. I’ve had Maori people tell me that their grandmothers used manuka honey on them. This is somewhat surprising because honey bees were only introduced to New Zealand in 1839, so manuka honey has not actually been around that long.

More recently, interest in trying manuka honey has grown amongst clinicians after we had carried out research targeted to show the effectiveness of manuka honey against the species of bacteria that are the major problem in causing infection of wounds. To a large part the uptake of usage of manuka honey has come from the demonstration in research that it is effective against antibiotic-resistant strains for which there is no effective treatment otherwise.

Why is manuka honey better than other honey?

Peter: That was the question raised by a friend, Kerry Simpson, who was a science teacher and very keen beekeeper. I’d been working on the antibacterial properties of mammalian peptides, and he persuaded me to look at manuka honey. Our hypothesis was that there was an antibacterial factor in manuka honey additional to the hydrogen peroxide that is produced enzymically in all honeys. To test this hypothesis we destroyed the hydrogen peroxide in samples of honey and found that manuka honey uniquely still had strong antibacterial activity. This has since been found to be due to methylglyoxal. Hydrogen peroxide is destroyed by the catalase enzyme in body tissues and the peroxidase enzyme in saliva, but methylglyoxal is not destroyed, so manuka honey keeps its full activity when other honeys lose a large part of theirs.

What future uses can you imagine for manuka honey?

Peter: It’s a real frustration to me that the potential uses are so slow in being realised. Getting manuka honey used more in wound care relied a lot on a few enthusiasts and patients, who may have read about it in the news media. That’s an unusual part of the manuka honey story – that the communication has been more important than the research. Even now the wound dressing products made from manuka honey haven’t really been subject to large scale trials. Big pharmaceutical companies aren’t going to spend millions of dollars testing something which they can’t have ownership over.

Manuka honey should really be the first treatment of choice for many skin infections. You don’t get the same problems with antibiotic resistance, and the antibiotics can be saved for systemic infections which honey can’t reach. Other uses include eye infections, nasal sinus infections and outer ear infections. I know that vets around Hamilton are already using a mixture of water and honey as ear drops for dogs.

Manuka honey also has real potential for cystic fibrosis. Because the disease affects the cell membrane transport system, patients get very thick mucous and suffer from a lot of lung infections. Sometimes these are almost completely resistant to antibiotics. Recently a teenage girl – whose only other choice was a lung transplant – had her infection completely cleared up by adding manuka honey to a nebuliser.

Aren’t bees in trouble worldwide?

Cliff: There are certainly issues, especially in countries with industrialised systems of horticulture. Beehives have to be purposely brought into large acreages of monoculture to provide essential crop pollination, and in the US in particular commercial beekeepers end up transporting their hives thousands of kilometres each season to do the job. They are paid for these pollination services, but they often face uncertain returns from honey production, and sometimes there just isn’t enough incentive to maintain and increase their hive numbers.

At the end of the book I try to put this into a bit of perspective, however. World food production is not actually at issue – 70% of our food, including things like wheat, rice and corn, don’t require insect pollination. It’s the remainder, including a number of fruits and some vegetables, that can be the problem, and the more industrialised the production system, the more essential is the need for paid pollination services.

New Zealand, as it turns out, is a good example of how if we are willing to pay good prices for bee products, then honey bees don’t inevitably have to disappear. Despite dire predictions at the turn of the century based on diseases and pests such as varroa, New Zealand now has two-thirds more hives, in large part because of increases in the price of manuka honey. Commercial beekeeping is now seen as an attractive occupation, young people are coming into the industry, and there are upwards of 15,000 hectares in areas like the Wairarapa and the central North Island that have been ear-marked for manuka re-generation.

Ironically, in much of this hill country the farmers were once paid by the government to destroy manuka. Now we’re seeing people starting to create manuka plantations, and the combination of carbon credits and manuka honey can make this development quite profitable. In fact, the Ministry of Primary Industries predicts that with such plantations the industry is likely to grow ten-fold to as much as NZ$1 billion per year. It’s a unique situation, since I can’t think of another example world-wide where a tree crop has been planted just for honey production.

Cliff Van Eaton’s Manuka: the biography of an extraordinary honey (Exisle Publishing), is a finalist for the 2015 Royal Society of New Zealand Science Book Prize.

These interviews are supported by the Royal Society of New Zealand, which promotes, invests in and celebrates excellence in people and ideas, for the benefit of all New Zealanders.