For thousands of years honey has been used both orally and topically as a natural remedy. All honey has the enzyme glucose oxidase – which releases hydrogen peroxide, an antiseptic. This is secreted into the honey by the bee when regurgitating nectar from the floral source. As a result all honeys have hydrogen peroxide present. However, this can be broken down by some enzymes (such as blood and tissue), rendering it less effective.
The native New Zealand Manuka bush (Leptospermum Scoparium) contains a special property that distinguishes it from all other honeys. Manuka honey has additional antibacterial properties which work after the hydrogen peroxide disappears (known as non-peroxide activity). This makes Manuka honey much more potent than other honeys.
These unique properties were discovered by New Zealand scientist Prof Peter Molan, who began his honey investigation in 1982. The numbering system 10+ 16+ 20+ 25+ was used to show the antibacterial efficacy of the honey when applied topically – 5+ was added later to show honey with some Manuka in it. This level does not have significant antibacterial strength.
Why you need the right sort of activity in Manuka Honey
Not all Manuka honeys are equal - some are more effective than others, and product labelling can be confusing or misleading. This video by Prof Peter Molan demonstrates in the laboratory why the special non-peroxide antibacterial activity that is in only some of the Manuka honey on sale is important, and why the type of antibacterial activity in other honey is not as good as is made out in its activity rating.