What does UMF mean?

UMF® in an acronym for 'Unique Manuka Factor' and is an antibacterial property which is present in Active Manuka Honey. UMF® is a floral property that comes from the nectar of Manuka flowers and has been found to possess extraordinary healing powers. This antibacterial activity is not present in any other type of honey.

What does NPA mean?

Stands for 'Non Peroxide Activity'. We use this because this is the terminology that is actually used on the lab certificates of analysis we obtain to rate each jar of honey. NPA isn’t a registered trade mark which means Green Bay does not pay marketing royalties for the use of industry trade marks - the cost of which is then passed to the consumer.

Genuine Manuka Honey is tested and rated for its antibacterial potency. Green Bay Harvest obtains a lab certificate for all its Manuka Honey. The lab certificate actually uses the scientific and generic (i.e. non-commercialised) terms ‘Peroxide Activity’ and ‘Non Peroxide Activity’ which is why Green Bay Harvest use the exact same terminology. Green Bay uses only the NPA score to rate its honey. The UMF® rating and all the other trade marked terms use the same (NPA) Non Peroxide Activity score of the honey from the lab certificate.

It is generally accepted that Manuka Honey with a UMF® or NPA rating of 10 or higher is appropriate for therapeutic use. The higher the UMF® (i.e. the NPA rating), the higher the antibacterial activity although there is an upper limit - typically about 15+  to the naturally occurring activity level of the honey when it is harvested fresh from the hive.

Can you trust the rating?

We are family business, and as owners we work directly in the business. We keep bees ourselves. We have an office and warehouse in Christchurch, New Zealand where all our buying is centralised with a long standing network of bee keepers and lab technicians whom we know personally and trust. All our Manuka Honey can be traced back to a lab certificate which has been issued by an ISO 9001 certified laboratory.

Why NPA is so important?

Research about the therapeutic benefits of Manuka Honey is based on the presence of NPA (Non Peroxide Activity) i.e. compounds in the honey that are bio-active and are attributable to the unique floral source of the honey - the Manuka bush (Leptospermum scoparium)  which is unique to New Zealand and commonly known as the Tea Tree.  

The rating and the lab tests that support it specifically exclude the Peroxide Activity, as to a great or lesser degree all honeys naturally contain Peroxide Activity.

Non Peroxide Activity vs. Peroxide Activity?

Peroxide Activity has mild anti-bacterial property however companies add the NPA & the Peroxide Activity which has mild therapeutic benefits together to achieve a higher score, not all Manuka Honey has NPA!

There are two golden rules that are simple to follow and will limit the risk of purchasing the Manuka Honey which is best value and best suited for your needs:

1. Don't go too high - If you see Manuka Honey for sale with a high activity score (NPA  above 15+) you should ask to see the lab certificate for the honey and check that the peroxide activity hasn't been combined with the NPA rating.  

Also remember to inspect the honey to see if it has a dark brown color and tastes or smells slightly burnt or caramelized. If it is, it’s possible the honey is quite old or has been heated or ‘cooked’ to artificially increase the NPA rating and save a penny on packing yields. When honey is cooked it becomes denatured, the live enzymes are destroyed and levels of a compound called HMF which is mildly toxic in high quantities is increased in the honey. EU law requires HMF levels of honey to be below 40 mg / kg but the reality is that honey is rarely tested for HMF by government agencies so ‘cooked’ honey often goes undetected.

2. Don't go too low - Remember that all clinical and academic research into Manuka Honey has shown that even if genuine, Honey with an activity score below 8+ has no proven therapeutic benefits.  Manuka Honey with low activity is perfect as a breakfast honey and will still have the distinctive manuka taste but don’t ascribe the amazing stories about Manuka Honey that abound in the media to Manuka Honey with low ratings.

The goldilocks number of Manuka Honey - All the amazing research about Manuka Honey has been conducted with 10+ Manuka Honey or above.  The ‘goldilocks’ activity score is 10+ to 15+.  

Green Bay has never sold Manuka Honey outside this range for the reasons above.

See more information below including some great offers on our range of Manuka Honey products

All Our Manuka Honey is backed by our Quality Assurance promise - 100% New Zealand Active Manuka Honey; Genuine Certified Non Peroxide Activity (NPA), unpasteurised, not fine filtered and taste tested.

The variation occurs in that the levels of activity in Manuka Honey was reported in a publication (Allen, K.L, Molan, P.C. and Reid, G.M, 1991.  A survey of Antibacterial Activity of some New Zealand Honey’s, journal of pharmacy & pharmacology 43, 817-822), where it was noted that the present survey has shown not all samples said to be Manuka Honey can be relied upon to provide this antibacterial activity.

Interesting Facts:-

• Taking 2 teaspoons of Manuka Honey 5+ is not the same as taking 1 teaspoon of 10+. The activity levels are not addictive.
• Not all Manuka Honey has Non Peroxide Activity
• Some Manuka Honey ratings may be misleading or incorrectly marked by marketers who are not familiar with the clinical research or do not interpret the scores on the laboratory analysis report correctly.
• There is not clinical or academic research to prove that Manuka Honey with a NPA score less than 8+ has any of the therapeutic effects associated with Manuka Honey with high NPA scores.
• Not all Manuka Honey has clinically proven anti-bacterial and anti-inflammatory properties.
• There are no Manuka Bees. Most of the honey bees in the world are actually Italian! Manuka Honey is made from normal honey bees who use nectar from the Manuka Flower to make their honey.
• Some Manuka Honeys on the market have extremely high Activity Scores because the Peroxide Activity and the Non Peroxide Activity ratings have been combined.
• Just like some people assume expensive wine is always better than another bottle with a lower price, most people assume that the higher the activity score on the label, the more they should expect to pay for their Manuka Honey and the better it will be for their health.
• Many consumers are used to buying a Manuka Honey by the activity number and simply assume the score relates to the Non Peroxide Activity.