What’s the difference between NPA, MG and UMF?
When I was growing up in NZ it was all just Manuka honey. You knew it tasted different from normal honey, you knew it was good if you had a sore throat, you knew it was a little bit more expensive but you could still buy it in the supermarket and we were allowed to put it on our toast.
So what’s the deal with all these letters and numbers that now appear on the labels? And that price tag?!
Here’s my take on it… (scroll to the bottom if you just want the summary :)
What is Manuka honey?
Honey made by bees who use nectar from the Manuka bush (leptospermum scoparium).
It is sometimes referred to as teatree because Captain Cook made a tea out of it’s leaves and is related to, but not the same as the melaleuca tree which is what we commonly think of as teatree. For example if you buy teatree oil, that is usually melaleuca.
Although traditionally thought of as a New Zealand only plant, Manuka bushes are also found in Tasmania, Victoria and NSW.
Over the past 20 years there’s been a lot of research into Manuka honey because of it’s remarkable antibacterial and antiseptic properties. We are talking serious medical uses such as wound healing and burns as well as the more low key uses of immune system boosting and fighting bacteria that cause sore throats.
There are two main types of antibacterial activity found in Manuka honey, hydrogen peroxide activity and non-peroxide activity.
What is hydrogen peroxide activity?
This is found in all honey and is a major reason for all types of honey being good for us.
What is non-peroxide activity (NPA)?
This is the additional antibacterial activity that Manuka honey has over and above other honeys which cannot be explained by hydrogen peroxide activity or pH.
How is NPA measured?
1. Honey solution has an enzyme added to remove the hydrogen peroxide activity.
2. Honey solution is applied to an agar plate infused with the bacteria staphylococcus aureus and incubated.
3. A control solution of a known antibacterial compound is also placed on agar plates for comparison.
4. Honey with NPA prevented growth of the bacteria so a measurable clear zone could be seen.
5. Honey with a clear zone equivalent to the standardised 10% solution is given a NPA rating of 10 and so on.
What is MG or MGO?
Subsequent research has led to the discovery of an active compound in Manuka honey called methylglyoxal (MG) which is thought to be a major contributor to the amazing level of anti-bacterial NPA in Manuka honey. MG seems to be present in much higher quantities in Manuka honey compared to any other honey. The researchers have been able to develop a conversion from NPA to MG. (see the table below)
MGO is a trademarked version of MG.
What is UMF?
Unique Manuka Factor (UMF) is a trademarked measuring system for NZ Manuka Honey. They measure 4 things:
1) leptosperin to ensure it’s genuine Manuka honey;
2) HMF to ensure it hasn’t been overheated;
3 & 4) MG and it’s precursor dihydroxyacetone to measure it’s anti-bacterial ability. These are all put together to determine the UMF rating. The UMF rating has the same number for it's equivalent NPA even thought they are measured differently.
So basically,
NPA = Non-Peroxide Activity = bacteria fighting ability specific to Manuka honey
MG/MGO = Methylglyoxal (mg/kg). A chemical believed to be the major contributor to the NPA.
UMF = Unique Manuka Factor. A NZ only, trademarked rating system which measures MG plus 3 other chemicals to ensure the quality of the Manuka honey.
TA (total activity) = Total Activity of hydrogen peroxide activity plus NPA. Doesn't prove it's Manuka honey.
In my opinion, a decent quality Manuka Honey has an NPA = 10, UMF = 10+ or MG of 250 or more.
Average cost for this is approximately $40 for 250g jar.
There are probably other, unmeasured/unlabelled Manuka honeys available that are just as good quality and cheaper but you wouldn't be able to distinguish them on taste, you need to research the brand.
How to use Manuka Honey:
At the first sign of a cough, tickly throat, cold, or even if you've just been around sick people, take 1 teaspoon of manuka honey morning and night.
Continue to take until you are certain you have no symptoms. Or if you develop symptoms, keep taking it until you are 100% clear.
Happy honeying!
