What Kratom Is, and How It Works

Welcome to Kratom University. The best place to start is the plant itself. Most people who buy kratom know a color and a name from the front of a package, and not much more. By the end of this lesson, you’ll know more than most.

This first lesson covers the tree kratom comes from, what is inside its leaf, and how that leaf becomes the powder you see. It also clears up a few things kratom gets confused with.

It All Starts With a Tree

Kratom is a tree. It is a tall evergreen. It grows in the warm, wet parts of Southeast Asia, in countries like Thailand and Malaysia. Its botanical name is Mitragyna speciosa, and it is a cousin of the coffee plant. The two belong to the same plant family.

Only the leaves are harvested¹. The bark, roots, flowers and wood are left alone.

Here’s something many buyers never hear. Every kratom product comes from this one tree. White, green and red are not different plants, and neither are the names printed beside them. It’s all the same leaf, grown in different places and handled in different ways. What the colors and names really mean comes up later in this level.

What’s Inside a Leaf?

Kratom leaves hold natural compounds called alkaloids². An alkaloid is simply a compound a plant makes on its own. You already know a few. Caffeine is an alkaloid, and so is nicotine.

Kratom has dozens of them. The one you’ll hear about most is mitragynine. University of Florida researchers describe it as the leaf’s main alkaloid. How big a share it holds depends on the tree. When scientists tested wild trees across Thailand, mitragynine made up anywhere from about 28 percent to about 69 percent of the leaf’s alkaloids.

A second one, 7-hydroxymitragynine, shows up in the leaf only in tiny traces. In a 2025 University of Florida study, it averaged just 0.02 to 0.04 percent of the alkaloids drawn from the leaf. It appeared only in certain seasons. As those researchers put it, leaf, fresh or dried, naturally holds only low amounts.

You may have seen products labeled 7-OH. Those are not kratom. They are synthetic, made in a laboratory. On July 6, 2026, the DEA published a proposal to bring those synthetic products under federal drug control. It withdrew that proposal on October 14, 2026 and published a new one in its place. Neither would place mitragynine, the leaf’s main alkaloid, in Schedule I. Both are proposals, and nothing in this lesson is a statement of what the law is³. This course is about natural kratom leaf, so 7-OH products are not part of it. We have never sold 7-OH products and we do not defend them.

Mitragynine and 7-hydroxymitragynine get most of the attention, but they are not the only alkaloids in the leaf.

No Two Leaves Are Quite the Same

Apples from two trees never taste exactly alike. Kratom leaves are the same way. Researchers at Kasetsart University in Thailand tested wild kratom trees across four regions of the country. Some leaves held about three and a half times as much mitragynine as others. Sunlight, humidity, soil and water all played a part.

Those were wild trees in one country, so the numbers do not describe any product you can buy. What they show is that kratom is a crop, and crops vary. Most kratom sold in the United States comes from farmed trees, and the next lesson covers where they grow. Wherever it grows, the leaf varies. That’s why each batch of powder is tested before it is sold.

From Leaf to Powder

The trip from branch to package is short. Leaves are picked by hand. The stems and the thick center vein are pulled out, since they don’t grind well. The leaves are dried, then milled into a fine green powder and sifted so the texture is consistent. Finally, the powder is tested, sealed and shipped out of the country where it grew.

Drying matters more than you might think. It changes what is in the leaf, and it’s part of the story behind kratom’s colors, which you’ll meet later in this level.

What Kratom’s Alkaloids Act On

We want to be upfront about this from day one. Your body has receptors, tiny sites on cells where compounds attach, a bit like a key fitting a lock.

Here’s the sentence we print on every page of this site. Kratom’s alkaloids interact with the same receptor systems that opioids act on. Kratom may be habit-forming. Kratom may be harmful to your health. The FDA has not approved kratom for therapeutic uses.

That does not describe what happens to any one person. It is the reason the next level is all about safety. The level after it covers what taking kratom regularly over months can lead to.

What Kratom Is Not

Three other plants often get mentioned alongside kratom, and they’re easy to tell apart.

Kava⁴ is the root of a shrub in the pepper family, from the islands of the Pacific. It isn’t related to kratom at all.

Kanna⁵ is a small succulent from South Africa, with its own, completely different alkaloids.

Coffee⁶ is kratom’s distant cousin. They share a plant family, but coffee is sold as a seed and kratom as a leaf.

Because they’re different plants, a lab number for kava or kanna tells you nothing about kratom.

Key Takeaways

• Kratom’s alkaloids interact with the same receptor systems that opioids act on. That’s why this course gives so much room to safety.
• In one study, some wild leaves held about three and a half times as much mitragynine as others. Two products with the same name may not match.
• Mitragynine is the leaf’s main alkaloid, but it’s one of dozens. A report that names two alkaloids is only a short list.
• Anything labeled 7-OH is synthetic and is not kratom. Natural leaf holds only a trace of 7-hydroxymitragynine.
• Every color and every name comes from the same tree. Read them on a package as labels, not as different plants.