What Is MGO in Manuka Honey?

If you've ever picked up a jar of Manuka honey, you've likely noticed a number like MGO 100+, MGO 400+, or even MGO 1000+ on the label. But what does that number actually mean — and does a higher number always mean better?

MGO stands for Methylglyoxal, a naturally occurring compound found in Manuka honey that is primarily responsible for its powerful antibacterial activity. The MGO rating tells you how many milligrams of Methylglyoxal are present per kilogram of honey. So MGO 400+ means there are at least 400 mg of Methylglyoxal per kilogram.

How Is the MGO Level Measured?

MGO concentration is measured through independent laboratory testing. Reputable Manuka honey producers send samples to accredited labs where scientists use high-performance liquid chromatography (HPLC) to precisely measure the Methylglyoxal content. The + sign in the rating means the honey has been tested and confirmed to contain at least that stated amount.

This is important: the rating is a guaranteed minimum, not an average. You can be confident the jar contains at least that MGO level.

The MGO Rating Scale at a Glance

MGO Rating Antibacterial Strength Typical Use
MGO 30–99 Low General eating, tea, toast
MGO 100–299 Moderate Daily wellness, immune support
MGO 300–499 High Gut health, sore throats, skin
MGO 500–799 Very High Targeted health support
MGO 800+ Ultra High Therapeutic, wound care

MGO vs. UMF: What's the Difference?

You may also encounter the UMF (Unique Mānuka Factor) rating on some jars. UMF is a broader quality trademark that measures multiple markers — including MGO, Leptosperin, and DHA — to verify authenticity and quality. The two scales are related but not identical:

  • UMF 5+ is roughly equivalent to MGO 83+
  • UMF 10+ is roughly equivalent to MGO 263+
  • UMF 15+ is roughly equivalent to MGO 514+
  • UMF 20+ is roughly equivalent to MGO 829+

Both systems are legitimate. MGO ratings are simpler and more straightforward for consumers who just want to know the Methylglyoxal concentration.

Does Higher MGO Always Mean Better?

Not necessarily — it depends on your intended use. For everyday enjoyment and general wellness, an MGO 100–300 honey is more than sufficient and considerably more affordable. You only need a high-grade MGO 500+ or above if you're using the honey for specific therapeutic purposes.

Additionally, very high MGO honeys tend to have a stronger, more distinctive — sometimes almost medicinal — flavour that not everyone enjoys for eating.

Key Takeaways

  1. MGO measures the Methylglyoxal content in mg per kg of honey.
  2. Higher MGO = stronger antibacterial properties.
  3. Choose your MGO level based on your specific needs and budget.
  4. Always look for independently tested and certified products.