Manuka Honey: MGO, Grades and What the Evidence Shows

Manuka honey is produced by bees that forage on the nectar of the Manuka bush (Leptospermum scoparium), a flowering shrub native to New Zealand and parts of southeastern Australia. Like all honey, it is mostly sugar and water. What sets it apart chemically is a high level of methylglyoxal (MGO), which forms from dihydroxyacetone (DHA), a compound found in unusually high concentrations in Manuka flower nectar. Ordinary honeys such as pure clover honey contain far less. MGO is what Manuka grades measure; no study shows that eating Manuka is healthier than eating other honey. MGO in Manuka honey ranges from under 100 mg/kg in low-grade jars to over 1,000 mg/kg in the highest grades.

Two grading systems are in common use. The UMF (Unique Manuka Factor) system is run by the UMF Honey Association in New Zealand, which licenses the trademark and audits producers. A UMF grade reflects several markers: MGO content, DHA levels, leptosperin (a chemical unique to Manuka nectar that confirms authenticity), and HMF (hydroxymethylfurfural, which indicates whether the honey has been overheated). The MGO system is simpler: it is the methylglyoxal content in milligrams per kilogram, as reported by the brand's lab. The published equivalences from the UMF Honey Association are: MGO 83+ equals UMF 5+, MGO 263+ equals UMF 10+, MGO 514+ equals UMF 15+, and MGO 829+ equals UMF 20+. A higher number means more MGO and a higher price. It is not a dose: no study shows that eating a higher grade does more for wellness, sore throats or digestion, and wound-care products are sterile dressings, not jars. Pick a grade by budget and taste, and look for a UMF or MGO number from a brand that publishes its test results.

The strongest human evidence is for honey dressings on burns, and it covers honey in general rather than Manuka in particular. A 2015 Cochrane review found, on high-quality evidence from 2 trials (992 people), that partial-thickness burns dressed with honey healed about 4.7 days sooner than with conventional dressings; for most other wounds the evidence was low or very low quality. Medihoney, a sterile medical-grade Manuka dressing, has FDA 510(k) clearance as a medical device for wound and burn care; that clearance covers the dressing, not jarred honey. For coughs and sore throats from colds, a 2021 systematic review in BMJ Evidence-Based Medicine (14 studies) found honey improved cough frequency and severity compared with usual care. The trials used buckwheat honey, eucalyptus and other honeys, not Manuka, and no trial shows Manuka works better than ordinary honey for a cough. No trial shows that eating Manuka clears an infection, heals an ulcer or prevents tooth decay. Claims that Manuka treats acne or eczema are not supported by trials; see a dermatologist for persistent skin problems.

Manuka honey is expensive, which makes it a target for mislabeling, and in 2018 New Zealand's Ministry for Primary Industries set a scientific definition that honey labeled Manuka for export must meet. This makes knowing how to identify authentic Manuka important. The first and most reliable indicator is a UMF or MGO certification mark on the label. The UMF Honey Association conducts independent testing and auditing of licensed producers, and only honey that passes its chemical analysis can carry the UMF trademark. Legitimate MGO-rated products are tested by laboratories, and good brands publish the results. Look for specific numbers (UMF 10+, MGO 263+) rather than vague claims like "Manuka blend" or "with Manuka honey," which often indicate products that contain only trace amounts of genuine Manuka. Verify the country of origin — authentic Manuka honey comes from New Zealand or, to a lesser extent, from specific regions of southeastern Australia where Leptospermum species grow. Many high-quality producers include a batch number and traceability information that allows you to verify the product's origin and testing results online. Price is a useful indicator: in our catalogue, the middle half of 17 verified manuka jars cost $29 to $71 (Oct 19, 2026), and a UMF 10+ jar lists at $34.99-54.99 — two to three times what Appalachian sourwood honey ($14-23) costs. If you see "Manuka honey" at bargain-basement prices, it's almost certainly not the real thing. Buy from reputable retailers, directly from certified New Zealand producers, or from specialty stores that can verify their supply chain.

Use Manuka the way you would any expensive honey: as food. Manuka's clinical reputation for wound care comes from sterile medical-grade dressings used under professional supervision — talk to a healthcare provider about wound management rather than treating wounds, burns, or abrasions with jarred honey at home. Many people eat it straight off the spoon or stirred into warm water or tea. Some people also use it in face masks, as a cosmetic. Its flavor is strong and earthy, and at $29 or more a jar there is no reason to bake with it: use a less expensive honey for cooking and baking. Like all honey, never give it to infants under 12 months.