For commercially competitive reasons there have been several symbols introduced into the market over recent years aimed to represent the strength of Manuka, such as UMF, NPA and MGO. While the NPA rating is the most widely recognised, we have transitioned to the MGO rating. The MGO rating is relatively easy to understand, as it is a direct measure of the amount of MGO (methylglyoxal) found in the honey, accurately quantified in mg/kg of honey. The higher the MGO number, the more MGO is found in that honey, corresponding to a higher antibacterial activity. The highest rating indicates a higher antibacterial activity level in the honey. Below is a simple table to assist with understanding the different ratings. Manuka Activity Rating Conversions MGO Rating Methylglyoxal NPA Rating Non-Peroxide Activity UMF Rating Unique Manuka Factor MGO 100+ NPA 6+ UMF 6+ MGO 300+ NPA 11+ UMF 11+ MGO 400+ NPA 13+ UMF 13+ MGO 550+ NPA 16+ UMF 16+