Is Heated Honey Toxic? What is HMF?

What Is HMF and Why Is It in Honey?

You may have heard claims that heating honey makes it toxic or dangerous. This myth has been shared often—but it’s not supported by science. The confusion usually centers around something called HMF, short for Hydroxymethylfurfural. While the name sounds chemical and intimidating, HMF is actually a natural compound found in many common foods.

In this post, we’ll explain what HMF is, why it shows up in honey, and how it compares to the levels you consume daily in other foods like coffee, bread, and fruit.

What Exactly Is HMF?

HMF, or 5-Hydroxymethylfurfural, forms when natural sugars in food are exposed to heat or stored for a long time. This reaction is part of what gives cooked or baked foods their rich, browned flavors—like in toast, caramel, or roasted coffee.

In honey, HMF forms very slowly over time or more rapidly when honey is heated. It’s used as a marker to help determine how much heat or aging the honey has undergone—not because it’s dangerous, but because fresh honey has very low levels.

Is Heated Honey Dangerous?

No. The idea that heated honey becomes poisonous is a myth. Even when honey is warmed to make it easier to bottle or pour, the levels of HMF remain very low—much lower than in many other foods we eat every day.

Food safety organizations around the world—including the World Health Organization (WHO) and the Codex Alimentarius—have set clear limits for acceptable HMF levels in honey:

• The maximum allowed is 40 mg/kg in most climates
• Up to 80 mg/kg is allowed in tropical regions where honey naturally warms faster

By comparison, many common foods contain much more HMF—and we eat them without any concern.

How Does Honey Compare to Other Foods?

Even if honey is moderately heated during processing, its HMF content stays far lower than many foods we eat daily. In fact, coffee alone is responsible for over half of the average person's HMF intake.

What About Raw Honey?

Raw, unheated honey—especially from clean, cold regions like Canada’s Boreal Forest—naturally contains very low levels of HMF, often under 10 mg/kg. At Oneroot Honey, we take great care to minimize any heat exposure and store our honey at cool temperature-controlled warehouse, preserving its quality, enzymes, and flavor—while keeping HMF low.

The Bottom Line

• HMF in heated honey is not dangerous—it’s a natural result of heating sugar-containing foods.
• Heated honey is not toxic, despite what the myths say.
• Honey contains less HMF than most cooked or baked foods, even after cooking/baking.

So go ahead and enjoy your honey—raw or heated—knowing it’s both safe and delicious.