UMF vs MGO — what the numbers actually mean

If you're staring at two jars of mānuka — one labelled 'UMF 15+' and another 'MGO 514+' — and wondering whether they're the same product, you're not alone. They are roughly equivalent, but they measure different things, and only one is a quality mark in the formal sense.

MGO — methylglyoxal in parts per million

MGO measures methylglyoxal directly — the compound mānuka honey produces in much higher quantities than other honeys, and the one most strongly correlated with mānuka's well-documented antibacterial activity. MGO is a raw chemical reading: 100 ppm, 263 ppm, 1,200 ppm, etc. Higher MGO = stronger antibacterial property.

UMF — Unique Mānuka Factor

UMF is a four-factor rating maintained by the UMF Honey Association (UMFHA). It tests for methylglyoxal, dihydroxyacetone (the precursor that becomes methylglyoxal as honey ages), leptosperin (a marker that confirms genuine mānuka origin), and HMF (a freshness indicator). UMF is the more comprehensive marker — it certifies authenticity and freshness alongside potency.

Rough conversion table

• UMF 5+ ≈ MGO 83+ — table grade, minimal antibacterial action
• UMF 10+ ≈ MGO 263+ — mid-range, daily eating tier
• UMF 15+ ≈ MGO 514+ — therapeutic threshold, used in clinical studies
• UMF 20+ ≈ MGO 829+ — premium therapeutic, wound-care grade
• UMF 25+ ≈ MGO 1,200+ — top of the practical range, rarely available

What the UMF doesn't tell you

Even within a UMF grade, two jars from different apiaries can taste markedly different — Northland mānuka has a smokier, more assertive profile; Marlborough mānuka leans floral and lighter; East Cape mānuka tends toward deep amber complexity. The rating is a chemistry number; flavour is regional and seasonal.