Manuka honey originates from New Zealand, where bees collect nectar primarily from the native Leptospermum scoparium (Manuka) plant. This honey has gained international recognition for properties beyond those of typical honey. Its potency is measured using a standardized metric called Methylglyoxal (MGO). MGO is the primary chemical marker responsible for the honey’s distinct non-peroxide activity, which sets it apart from other honeys.
Understanding MGO and Manuka Honey Grading
Methylglyoxal (MGO) is a compound that is present in high concentrations in Manuka honey, giving it a stable and potent antibacterial effect that does not rely on hydrogen peroxide, which is found in most other honeys. The source of MGO is Dihydroxyacetone (DHA), a precursor compound naturally present in the nectar of the Manuka flower. After the bees transform the nectar into honey, the DHA slowly converts into MGO as the honey matures.
The MGO grading system directly measures the concentration of this compound in the honey. The number on the label, such as MGO 300+ or MGO 550+, represents the minimum guaranteed milligrams of Methylglyoxal present per kilogram of honey (mg/kg). This measurement is performed in independent, certified laboratories. Higher MGO numbers indicate a greater concentration of this active compound, correlating to a more potent product.
Matching MGO Potency to Intended Use
The range of MGO levels allows consumers to select a product appropriate for their specific purpose. Lower-grade MGO Manuka honey (MGO 30+ to MGO 100+) is suitable for everyday consumption, such as a general food sweetener or for daily wellness support.
Mid-range potencies (MGO 200+ to MGO 400+) are chosen for more targeted daily intake, such as supporting general immune function or digestive health. These levels offer a moderate concentration of bioactive compounds.
Higher-grade Manuka honey (MGO 550+ and above) is reserved for specialized applications where maximum potency is desired. This includes short-term, intensive wellness support or topical application. The most potent grades, such as MGO 850+ or MGO 1000+, are used for advanced immune support and inflammation balance.
Beyond MGO: Other Markers of Quality
While MGO measures methylglyoxal content, it is not the only indicator of a Manuka honey’s overall quality. The Unique Manuka Factor (UMF) system is a comprehensive quality assurance and grading program for authenticity and potency. UMF is a licensed and audited quality mark that measures four signature compounds found in genuine Manuka honey.
The UMF rating includes MGO measurement, but it also tests for Leptosperin and Dihydroxyacetone (DHA). Leptosperin is a unique compound found only in Manuka nectar, acting as an authenticity marker to confirm the honey’s true origin. DHA is measured because it is the precursor to MGO, and its presence indicates the honey’s potential shelf life and future MGO conversion. The UMF system also measures Hydroxymethylfurfural (HMF), a compound that helps ensure the honey has not been overheated or aged excessively.
Ensuring Authenticity and Sourcing
The high value of Manuka honey means that product authenticity is a significant concern for consumers. To ensure a genuine purchase, the first step is to verify that the honey is a product of New Zealand, as this is the only source of true Manuka honey with its unique properties. Reputable brands will clearly state the country of origin on the label.
Consumers should look for official certification logos, such as the UMF trademark, which confirms the honey has undergone independent, third-party testing. For MGO-labeled honey, the MGO rating should be clearly displayed, and the producer should offer traceability information, sometimes provided through a QR code on the packaging. This code allows the consumer to verify the batch’s MGO level and origin. Finally, the label should specify if the product is “mono-floral,” meaning it is predominantly sourced from the Manuka flower, or “multi-floral,” indicating a blend with other floral sources.