Moringa: The Horseradish Tree and Its Leaves

1. What Exactly Is It?

Imagine smelling a basil leaf. It has a fragrance. The plant produces this fragrance itself, from water, air and light. Such self-made substances are called natural compounds. Moringa oleifera is a plant, known in German as the horseradish tree. The tree forms leaves, and these leaves contain many different natural compounds. Not just one, but a whole mixture. This is almost always the case with plants: A leaf is like a small kitchen where many things are created at the same time. For us humans, the leaves are first and foremost food. In some countries they are eaten like vegetables. Others dry them and grind them into a fine powder that is easier to store. Importantly: A natural compound is not a magic remedy. It is a substance that a plant produces, just like the lemon produces its sour juice. What a substance does in the body must be investigated individually. And because many substances come together in a leaf, it is not so easy to find out.

2. Where Does It Come From?

The horseradish tree is a tree. It has thin branches and many small, green leaves. When people talk about Moringa, they usually mean exactly these leaves. Many things are made from them. Some cook them like vegetables. Some dry them and grind them into a fine powder. In the studies this leaf powder often appears, because it is easy to measure and stores for a long time. The German name sounds like horseradish. Horseradish is the sharp white root you may know from the kitchen. Whether the tree tastes similar is not yet said by the name.

3. What Are the Researchers Investigating?

There are very many studies on Moringa, over a thousand in number. Most of them, however, are not studies with humans. Only 83 were carried out on humans, and only 36 of them were designed so that two groups could be compared. In such a comparison one group receives the leaf powder and the other does not, and no one knows who receives what. This is called a controlled study. What was researched? One study looked at how drinking water can be kept cleaner. In others the researchers examined how blood sugar behaves in people with a prediabetes stage, how blood pressure changes after eating and how the immune system reacts. Researchers have therefore asked many questions, but have not yet found a definitive answer to all of them. Some results come from small studies and must first be verified by others. Research on this continues.

4. An Experiment to Think About

Get three leaves from the kitchen: a basil leaf, a mint leaf and some parsley. Rub each leaf lightly between your fingers and smell it. Each one smells different. Why? Each plant produces its own fragrance substances. These are natural compounds that you perceive with your nose without seeing them. It is the same with substances that do not smell: You do not notice that they are there, and yet they are in the leaf. Now imagine you want to know whether a leaf helps a person. How would you find that out? You would have to form two groups, give both the same food and add the leaf to only one group. Afterwards you would have to observe for long enough. This is exactly how researchers do it.

For adults and professionals: the detailed page on Moringa oleifera (horseradish tree).