Curcumin in Turmeric: What the Percentages Mean

The curcumin content of turmeric is usually between about 2% and 7% by weight, depending on the variety, the growing conditions and how it was processed. Commercial turmeric powder averages roughly 3%, while high-curcumin types like Alleppey and Lakadong are quoted at around 5 to 7%. Supplement labels saying "95%" are describing a concentrated extract, not turmeric itself.

Those numbers get thrown around a lot on turmeric packs. This is how to read them without being misled.

What is curcumin, exactly?

Curcumin is the main yellow-orange pigment in turmeric. It belongs to a small family of compounds called curcuminoids. According to the Linus Pauling Institute at Oregon State University, curcumin makes up about 75% of the curcuminoids in turmeric, demethoxycurcumin about 10 to 20%, and bisdemethoxycurcumin less than 5%.

So when a label says "curcumin", it may mean curcumin alone or all three together. That small difference in wording can shift the number.

How much curcumin is in different kinds of turmeric?

Across all turmeric, curcuminoids are generally put at about 2 to 9%. Sources vary, so take any single number as approximate.

Does higher curcumin mean better turmeric?

For cooking, higher curcumin mostly means deeper colour and a stronger, earthier taste. You use a little less to get the same result. That's useful, and it's why high-curcumin varieties sell for more.

But curcumin is only part of what makes turmeric taste good. The aroma comes from essential oils, which fade with time and heat. A 3% powder that was ground recently can smell and taste better than a 6% powder that's been open for two years.

So it's a good number to know, but it isn't the whole story. Our hub guide on choosing a good turmeric powder covers the other checks that matter.

Why do curcumin numbers on labels vary so much?

The testing method

Labs use different methods. Spectrophotometry reads the overall yellow colour of an extract, which captures all curcuminoids together. HPLC separates each curcuminoid and measures them one by one. The two approaches don't always give the same answer for the same sample, so numbers from different labs aren't always comparable.

Dry weight and moisture

Some figures are given on a dry-weight basis, which makes them look a little higher than the same turmeric measured as sold.

Added colour

A colour-based test can't tell curcumin from an added yellow dye. That's one more reason to check suspiciously bright powder, as we explain in our post on checking turmeric for adulteration.

Questions worth asking a seller

• Is the figure for curcumin alone or total curcuminoids?
• Which batch was tested, and when?
• Which method was used?
• Is it on a dry-weight basis?

A seller who can answer calmly probably knows their product. One who can't may have copied the number from somewhere else.

What about curcumin and health?

Curcumin gets a lot of research attention. Even so, reviews of the evidence have not found high-quality clinical proof that turmeric or curcumin works as a medicine for any disease. It's also poorly absorbed. Most of what you eat passes straight through.

Curcumin supplements are a different thing from the turmeric in your dal. They're far more concentrated, and there have been reports of liver problems linked to them. They can also interact with some medicines, including blood thinners. Please talk to your doctor before taking one, and especially if you're pregnant or on regular medication.

Our honest position

We don't sell turmeric yet, but we plan to add it, and we'll only quote a curcumin figure if we can say where it came from. For now, you can read more about how turmeric is sorted in our turmeric grading guide, or browse the whole spices we pack.

Frequently asked questions

Is 95% curcumin the same as turmeric?

No. A 95% figure refers to a concentrated extract of curcuminoids, usually sold as a supplement. Turmeric powder itself contains only a few percent curcumin.

Does cooking destroy curcumin?

Some curcumin breaks down with long, high heat, and it also fades in light. Normal Indian cooking, where turmeric goes into hot oil or a simmering curry, still leaves plenty of colour and flavour in the dish.

Next time you see a percentage on a pack, you'll know which questions to ask.

Sources

• Linus Pauling Institute, Oregon State University: Curcumin
• FAO, Turmeric Post-Harvest Compendium
• Wikipedia, Lakadong turmeric