There are three different ratings used to assess the strength of New Zealand manuka honey products: MGO, NPA, and UMF. Without either rating, honey is low-grade and does not contain the beneficial benefits that make premium manuka honey very much in demand worldwide.

Breaking Down UMF, NPA and MGO Ratings

UMF stands for the Unique Manuka Factor. It tests the antibacterial performance of manuka honey against phenol, a known disinfectant, to determine the presence of the special non-peroxide activity. Therefore, the UMF rating has a one-on-one relationship to the phenol standard.
For labeling purposes, UMF is controlled by the UMFHA (UMF Honey Association).
NPA stands for non-peroxide activity.
When honey is mixed with water, hydrogen peroxide forms. Hydrogen peroxide is like bleach, and it is toxic to germs. Therefore, hydrogen peroxide is one of the main factors responsible for the antimicrobial effects of most honey varieties.
However, manuka honey does not depend on hydrogen peroxide because even without it, significant activity remains. New Zealand manuka honey is known for its non-peroxide activity.
Dr. Peter Nolan, was a pioneer in the manuka honey industry and found that the problem with NPA rating is that it’s not a direct measure of antibacterial activity.

Methylglyoxal (MGO) is a naturally occurring compound found in the nectar of the flowers of the Leptospermum species endemic to New Zealand. In 2008, it was discovered that MGO is responsible for much of the unusual activity of manuka honey. Therefore, the presence of MGO is found to be the best indicator of genuine active manuka honey with guaranteed antibacterial properties.
MGO graded honey directly measures the amount of MGO in manuka honey. Measurement is expressed as parts per million (ppm) or mg/kg. The higher the number the better the active and antibacterial properties, and more it is sought sought after in the health sector.
Here’s your guide to convert between MGO, UMF and NPA ratings.

UMF Rating
UMF 5+
UMF 5+
UMF 5+
UMF 10+
UMF 12+
UMF 15+
UMF 18+
UMF 20+

Why Choose MGO?
Following confusion in labeling, the New Zealand Government recommended that all manuka honey labeling should only show the actual methylglyoxal grade or quantity found after clinical testing. The results can be displayed as MG or MGO.
Extensive studies show that MGO is primarily responsible for the activity of manuka honey. MGO is responsible for the NPA of manuka honey. MGO forms from dihydroxyacetone (DHA) during the ripening of manuka honey. Therefore, the level of MGO found in manuka honey is dictated by the DHA content of the nectar, the foraging behavior of bees and the extent of the Leptospermum bloom.
Also, MGO levels can also be used to estimate the NPA whereas:
Manuka honey with MGO >260 mg/kg is predicted to have >10+ activity

Where to Buy MGO Certified Manuka Honey


Of the manuka honey sold in the market, only 2,000 to 3,000 tons are genuine. You could be buying counterfeit manuka honey yet still paying exorbitant fees. To ensure that you get MGO certified manuka honey, only buy from trusted producers in New Zealand.
PURAO manuka honey is harvested, packed and tested in New Zealand. It can be traced to the source and has been MGO certified by independent laboratories.
Every bottle of PURAO manuka honey and its manuka honey-rich products contain MGO and Leptosperin. MGO and Leptosperin are key markers that ensure the potency of manuka honey as antibacterial and anti-microbial, and for authenticity.
Leptosperin is unique to New Zealand manuka trees. It is naturally occurring and therefore, it cannot be replicated in the factories.
The presence of MGO and Leptosperin make PURAO unique and the best in the world.